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THE REPUBLIC OF ZAMBIA
MINISTRY OF LOCAL GOVERNMENT AND HOUSING
LUSAKA WATER AND SEWERAGE COMPANY
In Financial Cooperation
with
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project Detailed Engineering Design, Tender Documents, Detailed ESIAs and ESMPs for Water Supply and Sanitation Projects
CONSTRUCTABILITY REPORT
November 2012
9 November 2012
USACE Europe District
ATTN: Wayne Uhl
Konrad-Adenauer Ring 39
65187 Wiesbaden, Germany
Millennium Challenge Corporation
ATTN: Gail Chambers
875 Fifteenth St. NW
Washington, DC 20005-2221
Re: Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and ESMPs for
Water Supply and Sanitation Projects
Constructability Report
Dear Mr Uhl and Ms Chambers
We are pleased to submit the above referenced report under Task Order W912GB-12-D-0019-
0006. This report details the interactions between the selected water supply and sanitation sub-
projects, the constructability issues and the construction schedules as per the scope of the Task
Order.
Please do not hesitate to contact us if any clarifications or additional information are required.
Yours faithfully
Stefan Dörner
Program Manager
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
ESMPs for Water Supply and Sanitation Projects
Constructability Report
Gauff Ingenieure Page I
LUSAKA WATER SUPPLY, SANITATION
AND DRAINAGE (LWSSD) PROJECT
DETAILED ENGINEERING DESIGN, TENDER DOCUMENTS,
DETAILED ESIAS AND ESMPS FOR WATER SUPPLY AND
SANITATION PROJECTS
CONSTRUCTABILITY REPORT
Table of Contents
1. BACKGROUND ................................................................................................................................. 1-1
1.1 Scope of this Report .......................................................................................................................... 1-1
1.2 Aims and Objectives of the Constructability Report .......................................................................... 1-1
1.3 Organisation of the Report ................................................................................................................. 1-2
2. DESCRIPTION OF THE WORKS ..................................................................................................... 2-1
2.1 LP1 – Rehabilitation of Iolanda Treatment Works, Transmission and Distribution Centres .............. 2-1
2.2 LP6 – Primary Distribution Backbone Strengthening ........................................................................ 2-8
2.3 LS2 – Network Expansion in Central Branch .................................................................................. 2-10
2.4 LS3 – Network Expansion in Chelston Branch ................................................................................ 2-12
2.5 CSU15 – Chelston Pump Station Upgrade and Replacement ........................................................ 2-14
2.6 CSE44 – Sewer Expansion in Mtendere ......................................................................................... 2-16
2.7 CSU4 – Kaunda Square Interceptor Upgrade ................................................................................. 2-17
2.8 TU5 & TE3 – Kaunda Square Treatment Ponds Upgrade and Expansion ..................................... 2-19
2.9 Tabular Summary of Works Components........................................................................................ 2-21
2.10 Summary of Value of Components .................................................................................................. 2-22
2.11 Summary of Works Geographic Location ........................................................................................ 2-22
3. RECOMMENDED PACKAGING OF CONSTRUCTION CONTRACTS ......................................... 3-24
3.1 Packaging Rationale ........................................................................................................................ 3-24
3.2 Contract Package 1 – CP1, Rehabilitation of Iolanda Treatment Works, Transmission and Distribution Centres ......................................................................................................................... 3-24
3.3 Contract Package 2 – CP2, Primary Distribution Backbone Strengthening .................................... 3-24
3.4 Contract Package 3 – CP3, Water and Sewer Reticulation in the Kamanga, Mtendere, Kaunda Square and Chelston Areas ............................................................................................................. 3-25
3.5 Contract Package 4 – CP4, Kaunda Square Waste Stabilisation Ponds ........................................ 3-25
3.6 Contract Package 5 – CP5, Water Reticulation in Ndeke, Kwamwena, SOS Village, Chipata and Ng’ombe ........................................................................................................................................... 3-25
3.7 Overview of Contract Packages ...................................................................................................... 3-26
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
ESMPs for Water Supply and Sanitation Projects
Constructability Report
Gauff Ingenieure Page II
4. SUMMARY OF CONSTRUCTABILITY CHECKLISTS .................................................................... 4-1
5. PROJECT CONSTRUCTION SCHEDULE ....................................................................................... 5-1
5.1 Contract Package 1 – CP1, Rehabilitation of Iolanda Treatment Works, Transmission and Distribution Centres ........................................................................................................................... 5-1
5.2 Contract Package 2 – CP2, Primary Distribution Backbone Strengthening ...................................... 5-1
5.3 Contract Package 3 – CP3, Water and Sewer Reticulation in the Kamanga, Mtendere, Kaunda Square and Chelston Areas ............................................................................................................... 5-2
5.4 Contract Package 4 – CP4, Kaunda Square Waste Stabilisation Ponds .......................................... 5-2
5.5 Contract Package 5 – CP5, Water Reticulation in Ndeke, Kwamwena, SOS Village, Chipata and Ng’ombe ............................................................................................................................................. 5-3
Index of Tables
Table 2-1: Summary of Works Components in Sub-projects ....................................................................... 2-21
Table 2-2: Value Bracket Cost Ranges ........................................................................................................ 2-22
Table 2-3: Value Brackets of Sub-projects ................................................................................................... 2-23
Table 4-1: Constructability Checklist Summary Table .................................................................................... 4-1
Index of Figures
Figure 2-1: Location map of project intervention – LP1 .................................................................................. 2-2
Figure 2-2: Location map of project intervention – LP6 .................................................................................. 2-9
Figure 2-3: Location map of project intervention – LS2 ................................................................................ 2-11
Figure 2-4: Location map of project intervention – LS3 ................................................................................ 2-13
Figure 2-5: Location map of project intervention – CSU15 .......................................................................... 2-15
Figure 2-6: Location map of project intervention – CSE44 ........................................................................... 2-17
Figure 2-7: Location map of project intervention – CSU4 ............................................................................ 2-18
Figure 2-8: Location map of project intervention – TU5 & TE3 .................................................................... 2-20
Figure 2-9: Location map of all project interventions .................................................................................... 2-22
Figure 3-1: Location map of Contract Packages .......................................................................................... 3-26
Annexes
Annex I – Constructability Checklists
Annex II – Work Programmes
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
ESMPs for Water Supply and Sanitation Projects
Constructability Report
Gauff Ingenieure Page III
List of Acronyms and Abbreviations
AE Architect-Engineer (the Consultant: HP Gauff Ingenieure GmbH)
DC Distribution Centre
DI Ductile Iron
DN Nominal Diameter
ESIA Environmental and Social Impact Assessment
ESMP Environmental and Social Management Plans
FIDIC Federation of Consulting Engineers
FS Feasibility Study
GRZ Government of the Republic of Zambia
HDPE High Density Polyethylene
HL High Lift (pumps)
LV Low Voltage
LWSC Lusaka Water and Sewerage Company Limited
LWSSD Lusaka Water Supply, Sanitation and Drainage
LWW Lusaka Water Works
MCA-Z Millennium Challenge Account-Zambia
MCC Millennium Challenge Corporation
OD Outside Diameter
O&M Operations and Maintenance
PCB Polychlorinated Biphenyl
PF Power Factor
PS Pump Station
pH Power of Hydrogen
QM Quality Management
RTU Radio Transmission Unit
SCADA Supervisory Control and Data Acquisition
uPVC unplasticised Polyvinylchloride
USACE United States Army Corps of Engineers
USD United States Dollar
ZAF Zambian Air Force
ZESCO Zambia Electricity Supply Corporation
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
ESMPs for Water Supply and Sanitation Projects
Constructability Report
Gauff Ingenieure 1-1
1. BACKGROUND
The Government of the Republic of Zambia (GRZ) has identified access to clean and safe
water supply and adequate sanitation, drainage system and solid waste management in the
Capital City of Lusaka as key priorities and have worked with the Millennium Challenge
Corporation (MCC) to develop priority projects to be funded by MCC. The priority sub-
projects were identified in the “Investment Master Plans” for water supply, sanitation and
drainage financed by the MCC.
MCC and GRZ have agreed and signed a Compact program that focuses on the
improvement of water supply and sanitation infrastructure to enable the access to clean
and safe water supply and adequate sanitation services in the Capital City of Lusaka.
The Lusaka Water Supply, Sanitation and Drainage (LWSSD) project covers the
engineering design and tender documentation to source contracts for various sub-projects.
1.1 Scope of this Report
The scope of this report, as required by the Statement of work, is as follows:
The AE shall prepare and submit a Constructability Report that includes the following
elements:
Packaging of Construction Tender Documents
The AE shall investigate and report the potential to combine or split sub-projects into
manageable tender packages to achieve the following goals:
Minimize impacts to the local population to the extent possible, including minimizing
disruptions to existing utility services, combining water and sewer projects in
concurrent locations so that road excavation only occurs once; and,
Completion of all construction projects within the Compact timeline.
Sub-projects shall be split or combined into manageable tender sizes that maximize
competition to get the best value for LWSC and to allow for multiple parallel projects,
focusing each contractor’s efforts on a particular geography. An example of projects that
may be combined include LS1 (installation of bulk and consumer water meters) with LP6
(strengthening of the primary distribution system), the combination potentially split into
multiple contracts or lots that are geographically based.
Mitigation Strategy for Difficult Construction Conditions
AE shall identify strategies to develop specific language for consideration and inclusion in
the tender documents to protect MCC and MCA-Zambia from cost escalation and
construction overruns due to rainy season construction and drainage, flooding, high water
at the intakes, and unsuitable conditions in the project areas. The tender document shall
include a section on rock construction and blasting methodology or specialized equipment.
1.2 Aims and Objectives of the Constructability Report
The aims of the constructability review process are to:
1. Enhance Early Planning
2. Minimize Scope Changes
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
ESMPs for Water Supply and Sanitation Projects
Constructability Report
Gauff Ingenieure 1-2
3. Reduce Design Related Change Orders
4. Improve Contractors Productivity
5. Develop Construction-Friendly Specifications
6. Enhance Quality
7. Reduce Delays/Meet Schedules
8. Improve Public Image
9. Promote Construction Safety
10. Reduce Conflicts/Disputes
11. Decrease Construction/Maintenance Costs
The constructability review process should assure that:
The project, as detailed in the plans and specifications, can be constructed using
standard construction methods, materials and techniques.
The plans and specifications provide the contractor with clear, concise information
that can be utilized to prepare a competitive, cost-effective bid.
The work when constructed in accordance with the plans and specifications will
result in a project that can be maintained in a cost-effective manner by LWSC over
the life of the project.
The constructability report does not cover the LS1 sub-project.
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
ESMPs for Water Supply and Sanitation Projects
Constructability Report
Gauff Ingenieure 1-3
1.3 Organisation of the Report
Detailed constructability checklists have been prepared for each sub-project and these
include the following aspects; general, earthworks, pipelaying, structures, mechanical,
electrical, buildings, traffic accommodation, shutdowns, resettlement, environmental and
health & safety.
The checklists are included in Annex I, whilst Annex II contains the construction
programmes for the proposed contract packages.
This chapter introduces the broad project - its background and objectives.
Chapter 1: Introduction
This chapter describes the works contained in the various design packages that form part of the scope of works for the current assignment. The purpose is to summarise the works included in each so that similarities in works and geographical location can be easily identified.
Chapter 2: Description of the Works
This chapter uses the information in Chapter 2 to make recommendations for merging and breaking up the works contained in the various design packages into logical construction contract packages.
Chapter 3: Recommended packaging of Construction Contracts
This Chapter contains the constructability review of each of the design package. This is a checklist based review with summary tables of the major issues affecting each component of the project.
Chapter 4: Summary of Constructability Checklists
This chapter gathers the information on construction packaging and constructability issues and utilises it to recommend contract time scales for each construction package. Constraints on scheduling for each package are highlighted and a construction programme of work is presented for each contract package.
Chapter 5: Project Construction Schedule
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
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Constructability Report
Gauff Ingenieure 2-1
2. DESCRIPTION OF THE WORKS
2.1 LP1 – Rehabilitation of Iolanda Treatment Works, Transmission and Distribution
Centres
Under LP1, works were identified to accomplish the following objectives:
the rehabilitation of existing infrastructure, including civil works, electrical &
mechanical works and improvement of the water treatment process to reinstate the
design capacity to 110,000 m3/d from the present capacity of about 98,000 m3/d,
replacement of faulty pipe fittings along the transmission mains as well as within the
treatment plant and the distribution centres.
In order to achieve the above objectives, the following works are proposed:
Intake works at Kafue River: Physical inspections including levels on the roof and an
underwater camera examination showed that there was no settlement of the
structure. The electrical and mechanical work included an inspection of the
penstock gates, trash screens and four vertical turbine raw water pumps, which had
been installed under another contract in 2010 – 2011. These pumps were found to
be operating at their maximum current. Part of this high current is due to the
substantial voltage drop on the overhead aluminium power supply line. The actual
flow rates of these pumps were found to be less than the design capacity. Remedial
measures have been proposed including the replacement of the supply line. Other
works include the replacement of the trash screens and their retrieving system.
Iolanda water treatment plant and high lift (HL) pumps: the water treatment system
consists of coagulation flocculation, up-ward flow sedimentation and rapid gravity
filtration. Backwash of the filters is accomplished with air scour blowers and
backwash pumps. The sedimentation tanks have serious leakages from the
expansion joints. Such leakages were also found in the suction chamber of the high
lift pumps and in the treated water tanks. Remedial measures for these leakages
have been proposed. The backwash system has several leakages and the control
butterfly valves are worn out. This system will be rehabilitated by replacement of the
worn out components. The chemical dosing systems for flocculation with alum and
pH correction with lime are both in a dilapidated condition. These systems will be
rehabilitated. Disinfection is carried out by gaseous chlorine. Works have been
proposed to improve this system including safety aspects. The HL pumps were
found to be structurally sound and their performance was found to be at par with the
performance curves of these pumps. Their rehabilitation is therefore the
recommended option. While the Local Control Panel is in a sound condition, the MV
Switchboard and MCC are in a “fair wear and tear” condition. Spare parts are
getting more difficult to obtain for this switchboard and it is recommended that it be
replaced.
Chilanga Booster Station: this booster station is identical in almost all aspects to the
HL pump station at Iolanda. Therefore, similar corrective measures are
recommended for this facility.
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Foreign procurement - steel (or DI) pipes, fittings, pumps, switchgear
Local procurement - cement, aggregate, reinforcement
c. Preliminary Works
None
d. Temporary Works
None
e. Civil
None
f. Structural
Repair cracks and seal joints in various concrete structures
Remove loose bitumen/material, apply water proofing and provide a layer of
light aggregate on roofs of intake and reservoirs
Repair and construct new valve chambers on raw and treated water mains
g. Mechanical
Replace/ repair fittings on raw and treated water mains
Kafue Intake:
o The replacement of the intake trash screens and lifting mechanism
o Installation of ultra-sonic river water level gauge
o Installation of de-sludge submersible pumps (2 No.)
o Service of the penstock gates
Iolanda Water Treatment Plant
o Sedimentation Tanks
o Replacement of flash mixers (2 No.)
o Replacement of sludge cones and lifting equipment
o Replacement of decanting troughs
o Chemical Dosing
o Reinstatement of alum and lime dosing system
o Improvement of small power and lighting
o Improvement of chlorine dosing system
o Filters
o Rehabilitation of backwash pumps and appurtenances
o Replacement of air scour blowers (2 No.)
o Rehabilitation of backwash pipeline and system
o Replacement of filter backwash launders and siphons
o Replacement of filter drain penstock gates
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
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Gauff Ingenieure 2-4
o High Lift Pumps
o Rehabilitation of Ebara pumps (4 No.)
o Replacement of appurtenances including cone valves
Chilanga Booster Station
o Rehabilitation of Ebara pumps (4 No.)
o Replacement of appurtenances including cone valves
Stuart Park DC Booster Station (West and East)
o Rehabilitation of Booster Pumps (4 No.)
o Replacement of appurtenances
o Replacement of flow meter
o Improvement of chlorine dosing system
Chelston DC Booster Station
o Rehabilitation of Booster Pumps (4 No.)
o Replacement of appurtenances
o Replacement of flow meters
o Improvement of chlorine dosing system
7C DC Booster Station
o Rehabilitation of Booster Pumps (3 No.)
o Replacement of appurtenances
o Replacement of flow meter
Mass Media DC Booster Station
o Replacement of pumps (3 No.)
o Replacement of appurtenances
o Replacement of flow meters
o Improvement of chlorine dosing system
High Court DC Booster Station
o Rehabilitation of pumps (4 No.)
o Replacement of appurtenances
o Replacement of flow meters
Woodlands DC Booster Station
o Rehabilitation of pumps (3 No.)
o Replacement of appurtenances
o Replacement of flow meter
Lumumba DC Booster Station
o Replacement of old Pumps (2 No.)
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
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Gauff Ingenieure 2-5
o Replacement of appurtenances
o Replacement of flow meters
o Improvement of chlorine dosing system
Chawama DC Booster Station
o Replacement of old Pump (1 No.)
o Rehabilitation of Pump (1 No.)
o Replacement of appurtenances
o Replacement of flow meter
o Improvement of chlorine dosing system
Lusaka WW Plant 01
o Replacement of old Pumps (3 No.) to High Court
o Rehabilitation of Pumps (3 No.) to Woodlands
o Replacement of appurtenances
o Replacement of flow meters
o Improvement of chlorine dosing system
Lusaka WW Plant 02
o Replacement of old Pumps (2 No.)
o Replacement of appurtenances
h. Electrical
Kafue Intake:
o Replacement of the LV transformer (100 kVA)
o Replacement of overhead power line
o Replacement of underground power cable
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
o Installation of sensors and transmitters for SCADA
Iolanda Water Treatment Plant
o Sedimentation Tanks
o Rehabilitation of the flash mixer LV Switchboard and MCC
o Improvement of small power and lighting
o Chemical Dosing
o Improvement of small power and lighting
o Rehabilitation of the Alum LV Switchboard and MCC
o Rehabilitation of the Lime LV Switchboard and MCC
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
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Gauff Ingenieure 2-6
o Filters
o Rehabilitation of the Lime LV Switchboard and MCC
o Improvement of small power and lighting
o High Lift Pumps
o Replacement of Sub-main Switchboard and MCC
o Rehabilitation of the Local Control Panel
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
o Service of transformers
Chilanga Booster Station
o Replacement of Sub-main Switchboard and MCC
o Rehabilitation of the Local Control Panel
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
Stuart Park DC Booster Station (West and East)
o Replacement of Sub-main Incomer Switchboards (2 No.)
o Rehabilitation of LV Switchboard and MCC
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
o Service of transformers
Chelston DC Booster Station
o Replacement of LV Switchboard and MCC
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
o Service of transformers
7C DC Booster Station
o Replacement of LV Switchboard and MCC
o Replacement of cables
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
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Gauff Ingenieure 2-7
o Service of transformers
Mass Media DC Booster Station
o Rehabilitation of LV Switchboard and MCC
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
o Service of transformers
High Court DC Booster Station
o Rehabilitation of LV Switchboard and MCC
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
o Service of transformers
Woodlands DC Booster Station
o Rehabilitation of LV Switchboard and MCC
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
o Service of transformers
Lumumba DC Booster Station
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
o Service of transformers
Chawama DC Booster Station
o Rehabilitation of LV Switchboard and MCC
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
o Service of transformers
Lusaka WW Plant 01
o Rehabilitation of LV Switchboard and MCC
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
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Gauff Ingenieure 2-8
o Service of transformers
Lusaka WW Plant 02
o Replacement of LV Switchboard and MCC (for 2 pumps)
o Installation of cables
o Improvement of small power and lighting
o Installation of logic energy meter
o Installation of PF improvement capacitors
o Service of transformers
i. Building Works
Repair/ paint existing buildings at Kafue intake, Iolanda treatment plant and
DCs in Lusaka
j. Miscellaneous Works
Repair access roads and fences
Description of Specialist Components
Supply/ rehabilitation and installation of Iolanda and Chilanga high lift pumps
Safe removal and environmental disposal of PCBs from old transformers
2.2 LP6 – Primary Distribution Backbone Strengthening
The key component of this sub-project is the strengthening of the primary (backbone)
distribution system in order to efficiently transfer water received from Iolanda Treatment
works to the distribution centres within Lusaka City.
Approximately 20 km of DN 1200, DN 900 and DN 700 will be required for strengthening of
the existing primary distribution network. The planned works under LP6 include the
following new transfer pipelines:
Section 1: Laying a parallel DN 1200 line to the existing DN 900 between junction to
Lusaka Water Works (LWW) off the existing transmission main from Kafue and
Stuart Park, length 4,000 m.
Section 2: Laying a parallel DN 900 line to the existing DN 600 from Stuart Park
along Kamloops road and terminating at the roundabout on the Great East Road,
length 5,300 m.
Section 3: Laying a parallel DN 900 line to the existing DN 600 between junction to
LWW off the existing transmission main from Kafue and Lumumba reservoirs,
length 7,520 m.
Section 4: Laying a parallel DN 700 line to the existing DN 450 line along Mumbwa
road running from the roadside boreholes to Lumumba reservoir, length 3,010 m
(the existing line has numerous connections and will be used as a service line).
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
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Gauff Ingenieure 2-9
Implementation of the above measures will not only ensure efficient transfer of water within
the network but also ensure sufficiency in the primary distribution backbone especially once
more supply is availed to Lusaka from Kafue to meet the full 2015 demands.
Figure 2-2: Location map of project intervention – LP6
Description of Major Works Components
a. Pre-Contract Activities
Resettlement and compensation activities in locations where residents
encroached into the road wayleaves
b. Procurement Activities
Foreign procurement - steel (or DI) pipes, fittings
Local procurement - cement, aggregate, reinforcement
c. Preliminary Works
Confirm exact locations of existing underground services
d. Temporary Works
None
e. Civil
Pipelaying in steel (or DI) pipes with diameters DN 700 to DN 1200 (20 km)
Reinstatement of paved roads
f. Structural
Construction of reinforced concrete valve and washout chambers (precast
elements and in-situ)
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
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Gauff Ingenieure 2-10
g. Mechanical
Installation of isolation valves and air valves
h. Electrical
None
i. Building Works
Reconstruction of boundary walls, fences damaged by construction activities
j. Miscellaneous Works
None
Description of Specialist Components
In-situ welding of steel pipes
Pipe crossing by “pipe jacking” under the Kafue Road, the ZAF runway and three railway
crossings
2.3 LS2 – Network Expansion in Central Branch
The objective of the LS2 sub-project is to increase water coverage in the Central Branch
area of Lusaka, and improve water supply in Ng’ombe, SOS East and Chipata. Under LS2
the following is proposed:
Extension of secondary and tertiary networks into Central branch DMAs specifically
to Ng’ombe, SOS East and Chipata.
Supply and installation of consumer connections & water meters.
Construction of water kiosks.
Water expansion in the Ng’ombe (New Ng,ombe), SOS East and Chipata (North and
South) areas will consist of approximately 58 km of new pipelines varying in diameter from
OD 63 to OD 315.
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
Detailed Engineering Design, Tender Documents, Detailed ESIAs and
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Gauff Ingenieure 2-12
Installation of water meters
g. Electrical
None
h. Building Works
Construction of water kiosks
Reconstruction of boundary walls, fences damaged by construction activities
i. Miscellaneous Works
None
Description of Specialist Components
None
Geographical Location of Works
The New Ng’ombe, SOS East and Chipata (North and South) areas are located in the north
of Lusaka and can be accessed from the Great North Road and Great East Road
(Ng’ombe).
2.4 LS3 – Network Expansion in Chelston Branch
The objective of the LS3 sub-project is to increase water coverage in the Chelston branch
area of LWSC, and improve water supply in Mtendere, Kamanga, Kwamwena and Ndeke–
Vorna Valley. Under LS3 the following works are proposed:
Extension of Secondary and Tertiary Networks into Chelston branch DMAs
specifically Mtendere, Kamanga, Kwamwena and Ndeke-Vorna Valley
Supply and installation of consumer connections & water meters
Construction of kiosks
Drilling and equipping of boreholes (8 No. in Ndeke and 4 No. in Kwamwena)
Construction of one 750 m3 elevated and one 800 m3 ground reinforced concrete
reservoirs
Water expansion in the Mtendere, Kamanga, Kwamwena and Ndeke-Vorna Valley areas
will consist of approximately 280 km of new pipelines varying in diameter from OD 63 to
DN 500.
Lusaka Water Supply, Sanitation and Drainage (LWSSD) Project
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Gauff Ingenieure 2-14
e. Structural
Construction of a 750 m3 elevated reinforced concrete reservoir
Construction of a 800 m3 ground reinforced concrete reservoir
Construction of reinforced concrete valve and washout chambers (precast
elements and in-situ)
f. Mechanical
Installation of borehole pumps
Installation of new isolation valves, hydrants and air valves
Installation of water meters
g. Electrical
Extension of high voltage power line
Installation of transformers at boreholes
Installation of LV Switchboards and MCCs at boreholes
Installation of cables at boreholes
h. Building Works
Construction of water kiosks
Reconstruction of boundary walls damaged by construction activities
i. Miscellaneous Works
Fencing around reservoirs and boreholes
Description of Specialist Components
Drilling of boreholes
Use of specialist construction equipment where working width is less than 3.5 m and
resettlement is not economically practicable (some areas in Mtendere)
Construction of ground and elevated concrete reservoirs
Geographical Location of Works
The Mtendere, Kamanga, Kwamwena and Ndeke–Vorna Valley areas are located in the
northeast of Lusaka and can be accessed from the Great East Road.
2.5 CSU15 – Chelston Pump Station Upgrade and Replacement
The main objective of the works under this project component is to improve the
performance of the existing Chelston sewer pump station by rehabilitating the pump station
and its ancillaries, the force main of DN250 HDPE pipeline and to rectify the flooding
problem that is currently persistent. This will be achieved by demolishing the existing
structures, stripping sewage contaminated topsoil and raising the station above flood level.
All technical equipment and the force main to Chelston Ponds will be replaced.
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Figure 2-5: Location map of project intervention – CSU15
Description of Major Works Components
a. Preliminary Works
Demolition of existing dilapidated toilet and operations building structure
b. Temporary Works
Overpumping of sewage flows during station construction works
c. Civil
Pipelaying in buried DN250 HDPE pipe with ‘electrofusion’ joints
Platform earthworks in station ground level raising
Gravel access road construction
Excavation of open drainage
d. Structural
Structural concrete modification to an existing water retaining structure
e. Mechanical
Installation of new sewage duty submersible pumps.
f. Electrical
Upgrading of station power supply transformer
New electrical Motor Control Equipment associated with the new pumps
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New small power electrical system to building and security lighting
g. Building Works
Construction of a new operations building
Renovation works to an existing wall fence
h. Miscellaneous Works
None
Description of Specialist / Non Standard Works Components
None
Geographical Location of Works
Suburb of Chelston, Greater Lusaka.
2.6 CSE44 – Sewer Expansion in Mtendere
The sewer expansion programme focuses on the introduction of a new sanitation collection
and discharge system. The planned infrastructure intervention will provide an extensive
sewer network to enable approx. 100,000 residents, living in an area of approx. 400ha, to
connect to a sewer system. The network construction will consist of some 82 kilometres of
new gravity sewer lines ranging in diameter from OD 160 to DN 400.
Description of Major Works Components
a. Preliminary Works
Resettlement activities in locations where minimum working width of 3.5 m is
not available
b. Temporary Works
None
c. Civil
Pipelaying in uPVC sewer pipes OD 160 to DN 400
Reinstatement of paved roads
Reinstatement of unpaved roads
d. Structural
Modification of an existing pump station structure in in-situ reinforced
concrete
Construction of manholes from precast concrete elements
e. Mechanical
Installation of new sewage pumping equipment at the Salama pump station
f. Electrical
Upgrading of the electrical supply to the Salama Sewage Pump Station
g. Building Works
Reconstruction of boundary walls damaged by construction activities
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Construction of a new operator’s building at the Salama Pump Station
h. Miscellaneous Works
None
Description of Specialist Components
Installation of sewer pipe crossing of Great East Road by ‘pipe jacking’
Use of specialist construction equipment where working width is less than 3.5 m and
resettlement is not economically practicable
Geographical Location of Works
Township areas of Mtendere West and East with outfall lines to Salama Sewage Pump
Station (suburb of Avondale) and the Kaunda Square area, Greater Lusaka.
Figure 2-6: Location map of project intervention – CSE44
2.7 CSU4 – Kaunda Square Interceptor Upgrade
The Kaunda Square interceptor (CSU-4) crosses the eastern part of the city in a nearly
straight line from south to north, terminating at the Kaunda Square Ponds. Its alignment
follows the road along the north of Kaunda Square Stage II until the junction between
Kaunda Square Stages I and II and then heads northwest to the ponds crossing cultivated
fields and farm areas.
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The downstream portion of the Kaunda Square interceptor does not have adequate
hydraulic capacity during wet weather. It was not designed as a combined system but has
become one due to poor stormwater management in the area. To address these problems,
and to provide capacity for sewer expansion, approximately 2,800 m of the downstream
portion of the Kaunda Square interceptor will be upgraded. Upgraded diameters are in a
range of OD 315 up to DN 400 (uPVC) and DN500 to DN 900 (reinforced concrete).
Figure 2-7: Location map of project intervention – CSU4
Description of Major Works Components
a. Preliminary Works
Resettlement activities in wayleave clearing
Relocation of ZESCO infrastructure
b. Temporary Works
Overpumping during replacement of sections of live sewer line
c. Civil
Pipelaying in uPVC pipes diameters OD 315 to DN 400
Pipelaying in reinforced concrete pipes diameters DN 500 to DN 900
d. Structural
Construction of manholes from precast concrete elements
e. Mechanical
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None
f. Electrical
None
g. Building Works
Reconstruction of boundary walls disturbed by construction works
h. Miscellaneous Works
None
Description of Specialist Components
None
Geographical Location of Works
Kaunda Square suburb, Greater Lusaka. Accessed from the Great East Road at the PHI
roundabout.
2.8 TU5 & TE3 – Kaunda Square Treatment Ponds Upgrade and Expansion
The Kaunda Square Treatment Pond Upgrade and Expansion project component deals
with the rehabilitation, upgrading and expansion of the existing dilapidated ponds. The
proposed upgrading and expansion works (TU5 & TE3) are summarised as follows:
Modification of existing structures where possible;
Demolition and rebuilding of the rest of existing structure;
Removal of vegetation and dredging of ponds;
Construction of new anaerobic and facultative ponds, as wells as new sludge drying
beds;
A floating sludge removal facility (to be shared with other ponds);
Access road to the ponds site and service road and fencing around the ponds.
Description of Major Works Components
a. Preliminary Works
Acquisition of land for buffer and expansion area
b. Temporary Works
Dewatering and drainage of construction area
c. Civil
Stripping of topsoil to stockpile
Embankment forming in material obtained in cut
Road forming in gravel materials obtained from borrow
Provision of a small diameter water pipe connection to the Kaunda Square
water network.
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d. Structural
Construction of new grit screening facility
Construction of pond inlet and outlet structures in cast in-situ concrete
e. Mechanical
None
f. Electrical
Provision of a 380v, 3 phase overhead power connection
Building small power installation
g. Building Works
Construction of an operators building
h. Miscellaneous Works
Site fencing
Description of Specialist Components
Pond lining in fusion welded HDPE liners
De-sludging of existing ponds using floating dredging equipment which is to
be procured through the contract
Figure 2-8: Location map of project intervention – TU5 & TE3
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2.9 Tabular Summary of Works Components
Table 2-1: Summary of Works Components in Sub-projects
Sub-project LP1 LP6 LS2 LS3 CSU
4
CSE
44
CSU
15
TU5/
TE3
Work Item
Procurement
Foreign Procurement
Local Procurement
Temporary Over-pumping
Bulk earthworks
Pipelaying
Small diameter HDPE
Small diameter uPVC
Large diameter Concrete
Large diameter Steel
Domestic supply meters
Structural Concrete Work
Mechanical Works
Station Pipework
Large Valves and Meters
Pumps
Refurbish and reinstall
Electrical Works
Transformer Installations
Motor Control Centres
Small power systems
Building Works
Specialised Works
Pipe Jacking
Dredging
Borehole drilling
Resettlement Issues
Land acquisition
Clearing of wayleaves
Compensation
Environmental
Hazardous Wastes
Is a major component of the work
Is a minor component of the work
Is not included in the work
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Table 2-3: Value Brackets of Sub-projects
Sub-project Value Bracket
LP1 Large
LP6 Very Large
LS2 Medium
LS3 Very Large
CSU4 Small
CSE44 Large
CSU15 Small
TU5 & TE3 Large
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3. RECOMMENDED PACKAGING OF CONSTRUCTION CONTRACTS
This section of the report is intended to take the various sub-projects above and lump them
together and in some cases split them up in order to form works contract packages.
3.1 Packaging Rationale
The rationale used in selecting the works to go into each contract package is broadly as
follows:
1. Where possible all works in one geographical area should be carried out by the same
contractor. This minimises the amount of interaction between contractors and reduces
the chance of them interfering with each other’s work progress.
2. Where possible all works that are co-dependent are included in a single contract. In this
way the possibility of claims arising from a contractor due to the failure to perform by
another contractor is minimised.
3. Works of a dissimilar nature are generally kept in separate contracts unless they
represent a small part of the contract and can be easily subcontracted.
3.2 Contract Package 1 – CP1, Rehabilitation of Iolanda Treatment Works, Transmission
and Distribution Centres
Contract package CP1 will include all of the works in LP1. These works are largely
electromechanical and rehabilitation works with minor works in associated structural repairs.
This component contains much of the requirement for major, high impact shut downs which
will arise when the rising main is isolated for air valve replacement and when the reservoirs
are taken out of service for repairs. CP1 will therefore lead the programming of shut downs
and shut down windows for other contracts should be co-ordinated with this contract.
The performance of this contract is not in any way constrained by the performance of other
contracts.
The contract contains no resettlement or land acquisition activities.
The contract will fall into the ‘large’ value bracket.
3.3 Contract Package 2 – CP2, Primary Distribution Backbone Strengthening
Contract package CP2 will contain all the works in LP6. This consists of all large diameter
water primary distribution lines. The contract will have resettlement and compensation
issues, but requires no land acquisition. Some small duration shutdowns required for tie-ins,
but these can be co-ordinated with CP1 to prevent additional disruption. The performance
of this contract is not in any way constrained by the performance of other contracts.
This contract contains both the pipelaying through State House premises (along an existing
pipeline) and across the military ZAF city airport runway, both of which have been agreed to,
but will require special coordination during construction.
The contract will fall into the ‘very large’ value bracket.
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3.4 Contract Package 3 – CP3, Water and Sewer Reticulation in the Kamanga, Mtendere,
Kaunda Square and Chelston Areas
Contract Package CP3 has been assembled from various design package components to
arrive at a works contract covering the adjoining areas of Kamanga, Mtendere, Kaunda
Square and Chelston. It specifically contains the following:
LS3 works in the Kamanga area
LS3 works in the Mtendere area
all of CSE44, the Mtendere Sewershed expansion including the proposed pumping
station upgrade on Salama Farm
all of CSU4, the Kaunda Square Interceptor
all of CSU15, the Chelston sewage pump station and force main
As such the works contract contains all sewer components and both of the sewage
pumping stations within the same contract. In addition, water and sanitation pipe-laying in
the same geographical area are combined to prevent interference between contracts.
Grouping of CSE44 and CSU4 is advisable as the works are similar; sewage from CSE44
feeds into CSU4 and by combining the need for interfaces between contracts is eliminated.
The shutdown requirements associated with this Contract are minimal and localised.
The contract will have resettlement and compensation issues, but requires no land
acquisition.
The combined contract package will fall into the ‘very large’ value bracket.
3.5 Contract Package 4 – CP4, Kaunda Square Waste Stabilisation Ponds
The contract contains all of the works in TU5 and TE3 for the upgrading and expansion of
the Kaunda Square ponds. The contract involves civil and earthworks and has few
similarities to the other contracts in the area. A single interface is required between CP3
and this contract at the new plant intake structure. The ability to complete this component is
not linked to completion of other components so it can be safely left on its own.
This package has no shut down requirements.
The contract requires land acquisition.
The contract package will fall into the ‘large’ value bracket.
3.6 Contract Package 5 – CP5, Water Reticulation in Ndeke, Kwamwena, SOS Village,
Chipata and Ng’ombe
Contract Package CP5 has been assembled from various design package components to
arrive at a works contract containing the following:
LS3 in Ndeke/ Vorna Valley
LS3 in Kwamwena
All of LS2 in SOS village, Chipata Township and Ngombe Township
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4. SUMMARY OF CONSTRUCTABILITY CHECKLISTS
Annex I contains a constructability checklist for each of the design packages listed in
Chapter 3. At this stage of the design process the works have not been grouped into
construction Contract Packages (CP) so the constructability checks are carried out on the
individual sub-projects. The table below summarise the key points from the checklists.
Table 4-1: Constructability Checklist Summary Table
Works Package LP1 LP6 LS2 LS3 CSU
4
CSE
44
CSU
15
TU5/
TE3
Issues
Long Procurement Lead Times
Location of Existing Utilities
Access to Working Areas
Weather Disruption
Over-pumping and flow diversion
Geotechnical
Undefined geotechnical risk
Known rock occurrence
Blasting constraints
Known low bearing capacity
Groundwater in excavations
Traffic Accommodation
Public road traffic
Public access disruption
Shutdowns
Resettlement
Land Acquisition Required
Compensation for damage
Compensation for disruption
Environmental
Works largely unaffected by issue
Works moderately affected by issue
Works significantly impacted by issue
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5. PROJECT CONSTRUCTION SCHEDULE
Time schedules have been developed for each of the proposed contract packages. Key
considerations and constraints in the scheduling of each component are given below. In
addition to the specific programming requirements shown below the following general
requirements have been considered:
1. Construction contracts start on 1st October 2013 in accordance with the Feasibility
Study stage timings.
2. Pre-contract activities for resettlement and land acquisition issues will need to start
before 1st October and it is assumed that a 6 month lead time would be sufficient.
3. At the commencement of the project there are time allowances for procurement of
materials. These have been applied as follows:
a. Local supply materials – 3 months. These include small diameter HDPE and
uPVC pipes.
b. Foreign supply materials – 6 months. This includes electromechanical
equipment (except the Iolanda-Chilanga High Lift pumps) and large diameter
pipes.
4. It is assumed that the contractor will be mobilising during the first 3 months of the
contract and that there will be limited activity during this time.
5.1 Contract Package 1 – CP1, Rehabilitation of Iolanda Treatment Works, Transmission
and Distribution Centres
Lead time on electro- mechanical equipment, especially the new high lift pumps, will
be 6-12 months.
Once new pumps arrive old units can only be swapped out for refurbishment 1 at a
time in each pump station. Refurbishment of can only commence once the first new
pump is installed and it is expected that refurbishment will take on average 3
months per unit.
Therefore the contract requires a minimum time period of 24 months. This will result in an
average monthly cash flow of less than per month but with a very high cash
flow amount up front to procure the electromechanical equipment required. This
requirement should be considered in the framing of the contract document.
5.2 Contract Package 2 – CP2, Primary Distribution Backbone Strengthening
Large diameter pipes will be foreign purchased with lead times from order to pipes
arriving of 3-6 months.
Experience shows1 productivity not exceeding 2 km per month for large diameter
pipelaying in a built up areas. Therefore the pipelaying activity alone is programmed
at an average 1.5 km per month.
1 Experience from various projects of various sizes and duration, supervised by GAUFF in East and Southern Africa in the past five
years.
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Maximum average earning per month seen on recent contracts is between
and a maximum of million per month. Expected earnings
should not exceed per month.
Therefore this contract will require a time period of 24 months. Significant upfront cash flow
will be required for the procurement of pipes and fittings. This requirement should be
considered in the framing of the contract document. The contract contains provision for
separate payment for supply and installation of pipes and fittings which will ease the
requirements on the contractor’s cash flow.
5.3 Contract Package 3 – CP3, Water and Sewer Reticulation in the Kamanga, Mtendere,
Kaunda Square and Chelston Areas
80 km of small diameter sewer (<0.30m)
7.5 km of large diameter sewer (>0.30m)
60 km of small diameter water reticulation (<0.3m)
2 km of large diameter water reticulation (>0.3m)
Expected lead time on small pipes 3 months
Expected lead time on large pipes 3-6 months
Experience shows that productivity on pipe-laying for small pipes is in the range of
4km per team per month. Assuming 2 teams some 17 months will be needed to
complete the small diameter pipelaying
Pipe-laying for large diameter pipes will proceed at a rate not exceeding 2km per
month and will therefore require around 5-7.5 months.
5000 consumer meters in Mtendere will be installed at a rate on around 500 per
month, requiring 2 installation teams 10-12 months to complete
From the above, a 24 month contract duration is recommended. It is expected that small
diameter pipe procurement will continue throughout much of the duration of the works and
so will not place an undue burden on the contractor’s cash flow. The estimated average
cash flow is under .
5.4 Contract Package 4 – CP4, Kaunda Square Waste Stabilisation Ponds
The major work component is 300,000 m3 of bulk earthworks in forming the ponds.
Allowing for mobilisation and time lost to first rains plus the time required to dewater
the site earthworks will only commence in earnest 8 months after contract signing.
Programming the completion of earthworks works in 10 productive months, after
allowance for lost months in the second rainy season gives a requirement to
achieve 30,000 m3 per month. A typical earthworks team of 1 No. 20 ton excavator
will achieve 15,000 to 20,000 m3 per month. Therefore with 2 teams a ten month
period to complete earthworks is achievable. There is adequate space on site for 2
or more teams to work independently.
The contract requires the procurement of a dredge for desludging of the existing
ponds. This will be a long lead time item requiring 9 months from order to delivery.
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From the above a 24 month contract period is recommended. The estimated average
monthly cash flow is under per month and is considered achievable even with
disruption for rains.
5.5 Contract Package 5 – CP5, Water Reticulation in Ndeke, Kwamwena, SOS Village,
Chipata and Ng’ombe
Kwamwena -97 km small diameter pipe (<0.3m)
Ndeke – 94 km small diameter pipe (<0.3m)
SOS, Chipata, Ng’ombe – 50 km small diameter pipe (<0.3m)
The contract therefore requires a total of 240 km of small diameter pipe. Assuming
that a team is able to achieve 4 km per month 15 months will be required for pipe-
laying with at least 4 teams.
Total of 12,000 customer meters are to be installed. This can be achieved in 12
months by 4 teams at an aggregate rate of 1,000 meters per month.
From the above a 24 month contract period is recommended. The estimated average
monthly cash flow is under per month.
Lu
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LP1- Constructability Checklist
Checklist Item Constructability Further action required
1. GENERAL
1.1. Are areas available for:
1.1.1. Contractor’s camp and offices Suitable commercial rental properties are available within 5 km of the project area
1.1.2. Materials stockpiles As above
Most materials will be new and will be kept in secured Contractor’s stores
1.1.3. Disposal of waste materials Non soil waste to be disposed in Council designated waste dumps
Topsoil and unsuitable materials that cannot be disposed of on-site shall be disposed of in gravel material borrow pits
Removed equipment will be handed over to LWSC at Lusaka Water Works
Disposal of toxic material such as transformer dielectric oil will be handled and disposed of in accordance with the current local and international environmental regulations
Specifications to contain clauses for proper waste disposal
1.2. Are the necessary skilled personnel available in the local market and where necessary will the contractor be able to bring in staff from outside the country?
Required trades are available within Zambia. Immigration rules allow for management staff and staff with specialist skills to be brought from outside the country
1.3. Do the works require the importation of any high value items of specialist plant? If so have alternatives that eliminate this need been considered?
The works require importation of high value items such as pumps, controls, and large diameter gate valves, air valves etc. Items such as pumps and control panels are generally custom made and alternatives are very limited or unavailable
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Checklist Item Constructability Further action required
1.4. Will double handling of materials be involved?
Pumps, fittings, manhole covers, step irons, spindles, and control panels (etc.) will need to be stored in secured stores at the contractor’s yard and delivered to site at time of installation to prevent issues of theft/ vandalism and damage from elements
Concrete rings for manholes may be delivered directly to the point of use
1.5. Is there space for stockpiling of materials?
Yes
1.6. Are utility locations accurately defined?
Not applicable as works are being done in existing facilities.
1.7. Has the need for utility relocation been identified and have the costs been defined with the appropriate utility?
Not applicable
1.8. Access consideration
1.8.1. Are personnel work areas easily accessible?
All structures and work areas are easily accessible
Some works areas along the Treated Water Main are only accessible by foot. The works in these areas are limited to replacement/ servicing of fittings and installation of manhole chambers (etc.) Transportation of these items could be achieved by use of purpose made trolleys
1.8.2. Is there access for excavation plant?
No access constraints. Only manual excavation is envisaged
1.8.3. Is there access for haulage trucks to all areas they need to dump?
No access constraints
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Checklist Item Constructability Further action required
1.8.4. Are there traffic restrictions or congestion issues affecting site access?
No
1.8.5. Are there measures available such as opening up temporary access routes that would considerably improve constructability?
Not required
1.9. Will weather become a factor for the successful completion of the job?
Much of the works will be done indoors (electromechanical installation)
Excavation and backfilling operations for pipe and fitting replacements would become an issue in the heavy rainfall months of December to March
Major earthworks should be planned in dry months i.e. April to November
1.10. Efficiency of construction
1.10.1. Are there non-standard or complex methods of construction and could any of these be simplified?
No. Standard construction methods used throughout
Lifting equipment will be required
The contractor must provide a crane mounted truck as part of their main equipment
1.10.2. Has construction sequencing been considered in the design?
Yes. Replacement of pumps, valves and fittings etc. will be done in stages to allow for partial availability of plant and continued water production and supply
Include relevant specifications on shutdowns (also see Item 9)
1.11. Construction efficiency in specification
1.11.1. Are specifications adequate to meet functional requirements without being unnecessarily onerous which may introduce construction difficulties?
No non-standard specification provisions or tolerances have been introduced
Pumps are specified with the existing configuration in order to minimise pipe modifications
Further review of specification at 90% design
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Checklist Item Constructability Further action required
1.11.2. Have new items been introduced in the specifications/ method of measurement where standard items might suffice?
No
1.11.3. Do the specifications contain any restrictive clauses regarding source of material or equipment or manufacturing standard which may reduce options for competitive pricing?
All pumps, equipment and materials etc. will be specified in terms of functional requirements only
Where manufacturer’s names are used in the specifications or drawings, these are always suffixed with ‘or equivalent, or better’ to remove restriction whilst placing the emphasis on the contractor to demonstrate equality
1.12. Are pay items in the bid tabulation apparent in the specifications and in the drawings?
A standard specification and method of measurement is used (CESMM) and new items only introduced where the work items are not covered by the standard
Drawings need to contain cross references to pay items
Add cross references to drawings including tag numbers for mechanical equipment
Divide certain pay items in the BoQ such as concrete, earthworks etc. to indicate the location of the work
1.13. Are materials purchasing requirements simple to accurately extract from the Bill of Quantities?
CESMM bills use separate ‘supply’ and ‘install’ items for pipes and fittings
Mechanical and electrical components are individually itemised
Ensure ‘supply’ and ‘install’ quantities are consistent
Ensure all items of E&M equipment are uniquely referenced in drawings, specifications and BoQ
Ensure drawings contain sufficient labelling and callouts to reference with items in the BoQ
2. EARTHWORKS
2.1. Has the design been earthworks balanced to reduce the need for imported materials?
Not applicable
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Checklist Item Constructability Further action required
2.2. Where imported materials are required is the specification appropriate to the requirement?
Yes, for bedding and selected backfill to pipelines and fittings
3. PIPELAYING
3.1. Have the materials through which trenches are to be excavated been properly categorised?
Excavations for pipe and fitting replacements will be in existing backfilled trenches and around chambers
3.2. Have any potential areas of ‘hard’ or intermediate excavation been identified and have sufficient quantities of such excavation been allowed for in the BoQ?
Not applicable
3.3. Are trenches stable to the required digging depths or is shoring required. Do the specifications and drawings indicate the areas where shoring is required?
Excavations are mainly shallow and stable and no shoring will be required.
3.4. Is groundwater likely to be encountered in any excavations?
No
3.5. Is specialist equipment required and if so have alternatives been considered to eliminate the need for it?
No
3.6. Is rock likely to be encountered and has provision been made in the designs?
No
3.7. Is rock blasting possible or are alternative measures for rock removal required?
Not applicable
4. STRUCTURES
4.1. Are founding conditions suited to the structure foundation design?
Yes, for existing structures and new chambers
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4.2. Is sufficient working space available for structural works?
There are no constraints envisaged
5. MECHANICAL
5.1. Is mechanical equipment specified ‘standard’ and well supported with spares and technical knowledge?
All mechanical equipment is standard and regional availability has been checked. Sources for ‘‘special pumps – high lift ’’ have been identified too.
5.2. Is any long manufacturing lead time mechanical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment?
Yes, specifically for the Iolanda and Chilanga high lift pumps & motors. The equipment is functional specific and cannot be replaced by any “off the shelf equipment”.
Allow for manufacturing time of E&M equipment in construction program
5.3. Is all mechanical equipment accessible for installation, maintenance and replacement?
Manufacturer’s minimum space requirements have been adhered to
Lifting equipment will be used wherever lifting is required.
Trolleys will also be used for transporting heavy equipment over shorter distances.
5.4. Are the functional requirements of all mechanical equipment clearly indicated in the drawings or bills of quantities?
Drawings should include part numbers cross referencing detailed descriptions in the specification
Ensure cross referencing and detailed itemised descriptions of function and manufacturing requirements in specification.
6. ELECTRICAL
6.1. Are electrical standards used in design appropriate to local practice?
IEE standards used together with local ZESCO regulations
6.2. Is electrical equipment specified ‘standard’ and well supported with spares and technical knowledge?
All electrical equipment types are locally supported
6.3. Is any long manufacturing lead time electrical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment?
Yes, specifically for the Iolanda and Chilanga high lift pumps & motors. The equipment is functional specific and cannot be replaced by any “off the shelf equipment”
Allow for manufacturing time of E&M equipment in construction program
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6.4. Are electrical designs appropriate for tropical installation and have resilience to lightning strikes and power fluctuations been considered?
All electrical designs shall incorporate appropriate lightning protection
All designs are of a form commonly used in LWSC facilities. Robust starting equipment is specified
7. BUILDINGS
7.1. Are building materials specified readily available?
All are local stock items
7.2. Are founding conditions suited to the building foundation design?
Yes
8. TRAFFIC ACCOMMODATION
8.1. Is public access disrupted? No
8.2. Has access disruption to local businesses been considered?
Not applicable
8.3. Has provision been made to ensure local people have access to their properties?
Not applicable
8.4. Is there provision for a traffic management plan?
Not applicable
9. SHUTDOWNS
9.1. Will provision of water/ sanitation services be disrupted?
Yes, shutdowns will be needed at the intake, Iolanda treatment plant, Chilanga booster station and DCs when works are being rehabilitated/ replaced
Replacement of pumps, valves and fittings etc. will be done in stages so as to allow for partial availability of plant and continued water production and supply.
Specifications to contain clauses for partial shutdown of plants.
Specifications to indicate maximum period of disruption of water supply.
Specification/BoQ to include item for advertisement/ announcement of water supply disruption in local newspaper and on radio.
9.2. Is there provision for a shutdown management plan?
This will need to be agreed to with LWSC to minimise disruptions and coordinate between various work components
Specification to include requirements for shutdown management plan.
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10. RESETTLEMENT
10.1. Is sufficient survey data available to identify resettlement need?
Yes. The works will be done in existing facilities with no element of resettlement.
10.2. Has a resettlement corridor of impact been identified and constraints arising from it indicated in the drawings
Not applicable
10.3. Where the need for resettlement has been identified have design change options been considered to eliminate or reduce resettlement needs?
No resettlement required
10.4. Is sufficient space available for working without disruption to buildings and walls?
Yes
11. ENVIRONMENTAL
11.1. Have construction waste materials been identified and disposal methods specified?
Major arisings will be earth, crushed concrete and building rubble. The former can be disposed of in borrow pits whilst the latter two can be incorporated into site filling.
Minor arisings will be steel which can be recycled in Lusaka and timber which must be disposed of at landfill.
Specification to include landfill requirements. BoQ item to be provided for Council landfill disposal costs.
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11.2. Are any hazardous wastes expected and are safe disposal methods/ procedures specified?
Spillage of oils from pumps will have to contained and cleaned up.
Old transformers may contain oil with PCBs. Spillage of oil containing PCBs from Transformers may arise.
Some sludge from sedimentation tanks will arise which will have to be disposed of at licensed landfill site
Include containment and clean-up of any oil spills.
Mineral oil will be specified for new transformers.
Specification to include landfill requirements. BoQ item to be provided for Council landfill disposal costs.
12. HEALTH AND SAFETY
12.1. As designed, do the construction methods have any intrinsic safety issues? Have these been addressed in the specification?
Installation of heavy equipment should be done with help of lifting equipment.
Excavations are generally shallow and geotechnical investigations indicate stable trenching conditions.
The specifications need to contain detailed requirements for all installation of heavy equipment stating the minimum weight of the equipment that could be lifted manually.
12.2. Are National Health and Safety regulations sufficiently rigorous when compared to international best practice or should additional HS clauses be included?
Final ESIA will cover health and safety and will propose additional specification clauses
Include relevant HS clauses
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LP6- Constructability Checklist
Checklist Item Constructability Further action required
1. GENERAL
1.1. Are areas available for:
1.1.1. Contractor’s camp and offices Suitable commercial rental properties are available within 5 km of the project area
1.1.2. Materials stockpiles As above
1.1.3. Disposal of waste materials Non soil waste to be disposed in Council designated waste dumps
Topsoil and unsuitable materials that cannot be disposed of onsite shall be disposed of in gravel material borrow pits
1.2. Are the necessary skilled personnel available in the local market and where necessary will the contractor be able to bring in staff from outside the country?
Required trades are available within Zambia. Immigration rules allow for management staff and staff with specialist skills to be brought from outside the country
1.3. Do the works require the importation of any high value items of specialist plant? If so have alternatives that eliminate this need been considered?
None required
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1.4. Will double handling of materials be involved?
Steel pipes shall be stocked in available spaces along the pipeline routes and later transferred to the excavated trenches during installation
Steel pipeline fittings and appurtenances shall be stockpiled at the contractor’s yard and delivered to site at time of installation to prevent issues of theft/ vandalism
Earthworks materials and special bedding materials may be delivered directly to the point of use
1.5. Is there space for stockpiling of materials?
Space exists along the pipeline alignment for stringing of pipes and dumping of special bedding materials
1.6. Are utility locations accurately defined?
Overhead utilities (ZESCO and ZAMTEL) have been accurately surveyed and referenced on the drawings
Locations of existing underground cables and pipes have been obtained from the relevant utility providers and are shown on the drawings
1.7. Has the need for utility relocation been identified and have the costs been defined with the appropriate utility?
Some existing water pipelines shall need to be relocated
The estimated costs of relocation to be included in BoQs
1.8. Access consideration
1.8.1. Are personnel work areas easily accessible?
All structures and work areas are easily accessible
1.8.2. Is there access for excavation plant?
Section of pipeline route along State House fence shall need to be widened. This will involve demolition and reinstatement of an existing fence.
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1.8.3. Is there access for haulage trucks to all areas they need to dump?
No access constraints
1.8.4. Are there traffic restrictions or congestion issues affecting site access?
Several market stalls, business stalls and other temporary structures have been constructed along the pipeline way-leaves.
Will be addressed under the RAP consultancy
1.8.5. Are there measures available such as opening up temporary access routes that would considerably improve constructability?
Demolition of structures hindering access and constructability has been provided for
1.9. Will weather become a factor for the successful completion of the job?
Trenching and backfilling operations become an issue in the heavy rainfall months of December to March
Make allowances for reduced productivity in these months in the project timescale
1.10. Efficiency of construction
1.10.1. Are there non-standard or complex methods of construction and could any of these be simplified?
Use of ‘drilling/tunnelling’ method of construction may be adopted in laying pipelines under Kafue road or ZAF runway. These could be simplified if open trench excavation is permitted.
1.10.2. Has construction sequencing been considered in the design?
Yes. The pumping mains from LWW junction to Stuart Park and Lumumba Reservoirs shall be completed before work commences on the other two sections of the Lp6 pipeline. Hence increasing the amount of water available to be distributed to consumers as a priority.
1.11. Construction efficiency in specification
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1.11.1. Are specifications adequate to meet functional requirements without being unnecessarily onerous which may introduce construction difficulties?
No non-standard specification provisions or tolerances have been introduced.
Further review of specification at 90% design
1.11.2. Have new items been introduced in the specifications/ method of measurement where standard items might suffice?
No
1.11.3. Do the specifications contain any restrictive clauses regarding source of material or equipment or manufacturing standard which may reduce options for competitive pricing?
All equipment and materials etc. are specified in terms of functional requirements
Where manufacturer’s names are used in the specifications or drawings, these are always suffixed with ‘or equivalent, or better’ to remove restriction whilst placing the emphasis on the contractor to demonstrate equality
1.12. Are pay items in the bid tabulation apparent in the specifications and in the drawings?
A standard specification and method of measurement is used (CESMM) and new items only introduced where the work items are not covered by the standard
Drawings need to contain cross references to pay items
Add cross references to drawings including tag numbers for mechanical equipment
Divide certain pay items in the BoQ such as concrete, earthworks etc. to indicate the location of the work
1.13. Are materials purchasing requirements simple to accurately extract from the Bill of Quantities?
CESMM bills use separate ‘supply’ and ‘install’ items for pipes and fittings
Mechanical components are individually itemised
Ensure ‘supply’ and ‘install’ quantities are consistent
Ensure all items of equipment are uniquely referenced in drawings, specifications and BoQ
Ensure drawings contain sufficient labelling and callouts to reference with items in the BoQ
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Checklist Item Constructability Further action required
2. EARTHWORKS
2.1. Has the design been earthworks balanced to reduce the need for imported materials?
Yes. However, a number of sections of LP6 pipeline are very rocky and shall require imported material for backfilling.
2.2. Where imported materials are required is the specification appropriate to the requirement?
Yes. Details of quality of material for imported backfill are provided for in the specifications
3. PIPELAYING
3.1. Have the materials through which trenches are to be excavated been properly categorised?
Geotechnical investigations have characterised the materials throughout
3.2. Have any potential areas of ‘hard’ or intermediate excavation been identified and have sufficient quantities of such excavation been allowed for in the BoQ?
Extra-over excavation for areas with rock has been provided for in the BoQs
Extent and depth of intermediate excavation material to be marked on profile drawings cross referenced to geotechnical investigations
3.3. Are trenches stable to the required digging depths or is shoring required. Do the specifications and drawings indicate the areas where shoring is required?
No deep trenches. Geotechnical investigations showed stable trench walls throughout this area
3.4. Is groundwater likely to be encountered in any excavations?
None was detected within the influence zone of trenches during geotechnical investigations
3.5. Is specialist equipment required and if so have alternatives been considered to eliminate the need for it?
Steel welding equipment is required for large diameter pipe jointing. The equipment is specialist but relatively inexpensive and justified by the improved final product
3.6. Is rock likely to be encountered and has provision been made in the designs?
Yes. Extra-over excavation for areas with rock has been provided for in the BoQs
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Checklist Item Constructability Further action required
3.7. Is rock blasting possible or are alternative measures for rock removal required?
Non-explosive rock blasting is recommended where works are close to built-up areas and near high-voltage ZESCO power lines
Specifications to clearly state where non-explosive rock blasting is required and what type is acceptable (e.g. fractac, gas system, etc.)
4. STRUCTURES
4.1. Are founding conditions suited to the structure foundation design?
Yes. The ground conditions are suitable for the construction of reinforced concrete valve/ washout chambers
4.2. Is sufficient working space available for structural works?
No constraints
5. MECHANICAL
5.1. Is mechanical equipment specified ‘standard’ and well supported with spares and technical knowledge?
All mechanical equipment is standard and regional availability has been checked
5.2. Is any long manufacturing lead time mechanical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment?
None
5.3. Is all mechanical equipment accessible for installation, maintenance and replacement?
Manufacturer’s minimum space requirements have been adhered to
5.4. Are the functional requirements of all mechanical equipment clearly indicated in the drawings or bills of quantities?
Drawings should include itemised descriptions and BoQ should include cross referencing to the specifications
Ensure cross referencing and detailed itemised descriptions of function and manufacturing requirements in specification
6. ELECTRICAL
6.1. Are electrical standards used in design appropriate to local practice?
Not applicable
6.2. Is electrical equipment specified ‘standard’ and well supported with spares and technical knowledge?
Not applicable
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6.3. Is any long manufacturing lead time electrical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment?
None
6.4. Are electrical designs appropriate for tropical installation and have resilience to lightning strikes and power fluctuations been considered?
Not applicable
7. BUILDINGS
7.1. Are building materials specified readily available?
All are local stock items
7.2. Are founding conditions suited to the building foundation design?
Geotechnical investigations have confirmed founding conditions
8. TRAFFIC ACCOMMODATION
8.1. Is public access disrupted? There are several road crossings and 2 No. railway crossings
Ensure that dealing with access disruption is included in the specifications
8.2. Has access disruption to local businesses been considered?
Yes. Removal of market stalls and informal shops along the pipeline routes will be addressed in RAP.
Ensure inclusion in RAP
8.3. Has provision been made to ensure local people have access to their properties?
The specifications provide for temporary provision of access to people’s properties during construction
Ensure provision of temporary access during construction is included in the specifications
8.4. Is there provision for a traffic management plan?
Provision of ensuring control of traffic e.g. through placement of adequate signs and manual flagging is included in the specifications
Ensure provision of traffic management system is included in the specifications
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Checklist Item Constructability Further action required
9. SHUTDOWNS
9.1. Will provision of water/ sanitation services be disrupted?
Yes. Minor shutdowns are required for interconnections of the pipeline to Stuart Park and Lumumba reservoirs, existing pipeline at Munali roundabout and the junction next to Roadside boreholes. A one day shut-down shall be required at Chilanga Pumping Station to allow for the interconnection of the DN 1200 with existing DN 900 next to LWW.
Specifications to indicate maximum period of disruption of water supply.
Specification/BoQ to include item for advertisement/ announcement of water supply disruption in local newspaper and on radio
9.2. Is there provision for a shutdown management plan?
This will need to be agreed to with LWSC to minimise disruptions and coordinate between various work components
Specification to include requirements for shutdown management plan
10. RESETTLEMENT
10.1. Is sufficient survey data available to identify resettlement need?
Detailed topographical survey has picked up all walls and buildings near to pipelines.
10.2. Has a resettlement corridor of impact been identified and constraints arising from it indicated in the drawings
The RCOI has been defined and some market stalls along the pipeline route shall need to be removed to allow for the construction of the pipeline.
10.3. Where the need for resettlement has been identified have design change options been considered to eliminate or reduce resettlement needs?
Yes, the selected pipeline route has considered the best option where resettlement shall be minimal or none.
10.4. Is sufficient space available for working without disruption to buildings and walls?
No, some areas shall require buildings, and walls which are in the road wayleaves to be removed to allow for the construction of the pipeline
Ensure inclusion in RAP
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Checklist Item Constructability Further action required
11. ENVIRONMENTAL
11.1. Have construction waste materials been identified and disposal methods specified?
Major arisings will be earth, crushed concrete and building rubble. The former can be disposed of in borrow pits whilst the latter two can be incorporated into site filling
Minor arisings will be steel which can be recycled in Lusaka and timber which must be disposed of at landfill
Specification to include landfill requirements. BoQ item to be provided for Council landfill disposal costs
11.2. Are any hazardous wastes expected and are safe disposal methods/ procedures specified?
None
12. HEALTH AND SAFETY
12.1. As designed, do the construction methods have any intrinsic safety issues? Have these been addressed in the specification?
Some pipelaying works need to be carried out parallel to high and low voltage power lines. Discussions with ZESCO have indicated that some of these lines may be shut down to accommodate the works. Otherwise special care must be undertaken whilst working in these areas, especially the area between LWW and Lumumba DC
Open trenches are a safety hazard and will need to be properly fenced off and closed as soon as possible
Excavations are shallow and geotechnical investigations indicate stable trenching conditions
The specifications need to contain detailed requirements for works near power lines
The specifications need to contain detailed requirements for health and safety regarding trenches, dust, etc.
12.2. Are National Health and Safety regulations sufficiently rigorous when compared to international best practice or should additional HS clauses be included?
Final ESIA will cover health and safety and will propose additional specification clauses
Include relevant HS clauses
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LS2- Constructability Checklist
Checklist Item Constructability Further action required
1. GENERAL
1.1. Are areas available for:
1.1.1. Contractor’s camp and offices Suitable commercial rental properties are available within 5 km of the project area
1.1.2. Materials stockpiles As above
1.1.3. Disposal of waste materials Non soil waste to be disposed in Council designated waste dumps
Topsoil and unsuitable materials that cannot be disposed of onsite shall be disposed of in gravel material borrow pits
1.2. Are the necessary skilled personnel available in the local market and where necessary will the contractor be able to bring in staff from outside the country?
Required trades are available within Zambia. Immigration rules allow for management staff and staff with specialist skills to be brought from outside the country
1.3. Do the works require the importation of any high value items of specialist plant? If so have alternatives that eliminate this need been considered?
None required
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Checklist Item Constructability Further action required
1.4. Will double handling of materials be involved?
Steel pipes shall be stocked in available spaces along the pipeline routes and later transferred to the excavated trenches during installation
uPVC pipes, steel fittings and appurtenances shall be stockpiled at the contractor’s yard and delivered to site at time of installation to prevent issues of theft/ vandalism
Earthworks materials and special bedding materials may be delivered directly to the point of use
1.5. Is there space for stockpiling of materials?
Space exists along the pipeline alignment for stringing of pipes and dumping of special bedding materials
1.6. Are utility locations accurately defined?
Overhead utilities (ZESCO and ZAMTEL) have been accurately surveyed and referenced on the drawings
Locations of existing underground cables and pipes have been obtained from the relevant utility providers and have been shown on the drawings
1.7. Has the need for utility relocation been identified and have the costs been defined with the appropriate utility?
Some existing water pipelines shall need to be relocated
The estimated costs of relocation to be included in BoQs
1.8. Access consideration
1.8.1. Are personnel work areas easily accessible?
All structures and work areas are easily accessible
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1.8.2. Is there access for excavation plant?
Some sections are accessible only along the main roads servicing Ng’ombe, Chipata and northern part of SOS East. Several other streets have been reduced to narrow paths because of informal housing and market stalls constructed within the way-leaves. These have left limited space to lay the pipelines except in the middle of the paths/roads.
No access constraints in SOS East except for a very small section in the north
Will be addressed under the RAP consultancy
1.8.3. Is there access for haulage trucks to all areas they need to dump?
No access constraints
1.8.4. Are there traffic restrictions or congestion issues affecting site access?
Several streets have been reduced to narrow paths because of informal housing and market stalls constructed within the way-leaves
1.8.5. Are there measures available such as opening up temporary access routes that would considerably improve constructability?
Demolition of structures hindering access and constructability has been provided for
1.9. Will weather become a factor for the successful completion of the job?
Trenching and backfilling operations become an issue in the heavy rainfall months of December to March
Make allowances for reduced productivity in these months in the project timescale in the Contract Document
1.10. Efficiency of construction
1.10.1. Are there non-standard or complex methods of construction and could any of these be simplified?
No. Standard construction methods used
throughout
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Checklist Item Constructability Further action required
1.10.2. Has construction sequencing been considered in the design?
Yes. The secondary mains and water kiosks are planned to be completed before work commences on the tertiary mains and house connections.
1.11. Construction efficiency in specification
1.11.1. Are specifications adequate to meet functional requirements without being unnecessarily onerous which may introduce construction difficulties?
No non-standard specification provisions or tolerances have been introduced.
Further review of specification at 90% design
1.11.2. Have new items been introduced in the specifications/ method of measurement where standard items might suffice?
No
1.11.3. Do the specifications contain any restrictive clauses regarding source of material or equipment or manufacturing standard which may reduce options for competitive pricing?
All equipment and materials etc. are specified in terms of functional requirements
Where manufacturer’s names are used in the specifications or drawings, these are always suffixed with ‘or equivalent, or better’ to remove restriction whilst placing the emphasis on the contractor to demonstrate equality
1.12. Are pay items in the bid tabulation apparent in the specifications and in the drawings?
A standard specification and method of measurement is used (CESMM) and new items only introduced where the work items are not covered by the standard
Drawings need to contain cross references to pay items
Add cross references to drawings including tag numbers for mechanical equipment
Divide certain pay items in the BoQ such as concrete, earthworks etc. to indicate the location of the work
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Checklist Item Constructability Further action required
1.13. Are materials purchasing requirements simple to accurately extract from the Bill of Quantities?
CESMM bills use separate ‘supply’ and ‘install’ items for pipes and fittings
Mechanical components are individually itemised
Ensure ‘supply’ and ‘install’ quantities are consistent
Ensure all items of equipment are uniquely referenced in drawings, specifications and BoQ
Ensure drawings contain sufficient labelling and callouts to reference with items in the BoQ
2. EARTHWORKS
2.1. Has the design been earthworks balanced to reduce the need for imported materials?
Yes. However, some areas are rocky and will require imported material for backfilling.
2.2. Where imported materials are required is the specification appropriate to the requirement?
Yes. Details of quality of material for imported backfill are provided for in the specifications
3. PIPELAYING
3.1. Have the materials through which trenches are to be excavated been properly categorised?
Geotechnical investigations have characterised the materials throughout
3.2. Have any potential areas of ‘hard’ or intermediate excavation been identified and have sufficient quantities of such excavation been allowed for in the BoQ?
Extra-over excavation for areas with rock has been provided for in the BoQs
Extent and depth of intermediate excavation material to be marked on profile drawings and cross referenced to geotechnical investigations
3.3. Are trenches stable to the required digging depths or is shoring required. Do the specifications and drawings indicate the areas where shoring is required?
No deep trenches. Geotechnical investigations showed stable trench walls throughout the areas under LS2
3.4. Is groundwater likely to be encountered in any excavations?
None was detected within the influence zone of trenches during geotechnical investigations
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Checklist Item Constructability Further action required
3.5. Is specialist equipment required and if so have alternatives been considered to eliminate the need for it?
No specialist equipment is required
3.6. Is rock likely to be encountered and has provision been made in the designs?
Yes. Extra-over excavation for areas with rock has been provided for in the BoQs.
3.7. Is rock blasting possible or are alternative measures for rock removal required?
Non-explosive rock blasting is recommended where works are close to built-up areas and near high-voltage ZESCO power lines
Specifications to clearly state where non-explosive rock blasting is required and what type is acceptable (e.g. fractac, gas system, etc.)
4. STRUCTURES
4.1. Are founding conditions suited to the structure foundation design?
Yes. The ground conditions are suitable for the construction of water kiosks and valve/washout chambers
4.2. Is sufficient working space available for structural works?
No constraints
5. MECHANICAL
5.1. Is mechanical equipment specified ‘standard’ and well supported with spares and technical knowledge?
All mechanical equipment is standard and regional availability has been checked
5.2. Is any long manufacturing lead time mechanical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment?
None
5.3. Is all mechanical equipment accessible for installation, maintenance and replacement?
Manufacturer’s minimum space requirements have been adhered to
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Checklist Item Constructability Further action required
5.4. Are the functional requirements of all mechanical equipment clearly indicated in the drawings or bills of quantities?
Drawings should include itemised descriptions and BoQ should include cross referencing to the specifications
Ensure cross referencing and detailed itemised descriptions of function and manufacturing requirements in specification
6. ELECTRICAL
6.1. Are electrical standards used in design appropriate to local practice?
Not applicable
6.2. Is electrical equipment specified ‘standard’ and well supported with spares and technical knowledge?
Not applicable
6.3. Is any long manufacturing lead time electrical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment?
None
6.4. Are electrical designs appropriate for tropical installation and have resilience to lightning strikes and power fluctuations been considered?
Not applicable
7. BUILDINGS
7.1. Are building materials specified readily available?
All are local stock items.
7.2. Are founding conditions suited to the building foundation design?
Geotechnical investigations have confirmed founding conditions.
8. TRAFFIC ACCOMMODATION
8.1. Is public access disrupted? There are several street crossings within project areas of LS2. Similarly, some of the internal streets of Ng’ombe and Chipata are narrow and normal movement of public shall be disrupted during construction.
Ensure that dealing with access disruption is included in the specifications
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Checklist Item Constructability Further action required
8.2. Has access disruption to local businesses been considered?
Yes. Removal of market stalls and informal shops along the pipeline routes will be addressed in RAP.
Ensure inclusion in RAP
8.3. Has provision been made to ensure local people have access to their properties?
The specifications provide for temporary provision of access to people’s properties during construction
Ensure provision of temporary access during construction is included in the specifications
8.4. Is there provision for a traffic management plan?
Provision of ensuring control of traffic e.g. through placement of adequate signs and manual flagging is included in the specifications
Ensure provision of traffic management system is included in the specifications
9. SHUTDOWNS
9.1. Will provision of water/ sanitation services be disrupted?
Yes. Minor shut-downs will be necessary to allow for the interconnections of the new pipelines to existing pipelines. These shall be done by manually operating the sluice/gate valves that are nearest to the interconnection points.
Specifications to indicate maximum period of disruption of water supply
Specification/BoQ to include item for advertisement/ announcement of water supply disruption in local newspaper and on radio.
9.2. Is there provision for a shutdown management plan?
This will need to be agreed to with LWSC to minimise disruptions and coordinate between various work components
Specification to include requirements for shutdown management plan
10. RESETTLEMENT
10.1. Is sufficient survey data available to identify resettlement need?
Detailed topographical survey has picked up all walls and buildings near to pipelines
10.2. Has a resettlement corridor of impact been identified and constraints arising from it indicated in the drawings
The RCOI has been defined and some buildings and market stalls along the pipeline routes shall need to be removed to allow for the construction of the pipelines
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10.3. Where the need for resettlement has been identified have design change options been considered to eliminate or reduce resettlement needs?
Yes, the selected pipeline route has considered the best option where resettlement shall either be minimal or none
10.4. Is sufficient space available for working without disruption to buildings and walls?
No, some areas shall require some buildings, walls amongst other structures to be moved to allow for the construction of the pipelines.
Ensure inclusion in RAP
11. ENVIRONMENTAL
11.1. Have construction waste materials been identified and disposal methods specified?
Major arisings will be earth, crushed concrete and building rubble. The former can be disposed of in borrow pits whilst the latter two can be incorporated into site filling
Minor arisings will be steel which can be recycled in Lusaka and timber which must be disposed of at landfill
Specification to include landfill requirements. BoQ item to be provided for Council landfill disposal costs
11.2. Are any hazardous wastes expected and are safe disposal methods/ procedures specified?
None
12. HEALTH AND SAFETY
12.1. As designed, do the construction methods have any intrinsic safety issues? Have these been addressed in the specification?
Open trenches are a safety hazard and will need to be properly fenced off and closed as soon as possible
Excavations are shallow and geotechnical investigations indicate stable trenching conditions
The specifications need to contain detailed requirements for health and safety regarding trenches, dust, etc.
12.2. Are National Health and Safety regulations sufficiently rigorous when compared to international best practice or should additional HS clauses be included?
Final ESIA will cover health and safety and will propose additional specification clauses
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LS3- Constructability Checklist
Checklist Item Constructability Further action required
1. GENERAL
1.1. Are areas available for:
1.1.1. Contractor’s camp and offices Suitable commercial rental properties are available within 5 km of the project area
1.1.2. Materials stockpiles As above
1.1.3. Disposal of waste materials Non soil waste to be disposed in Council designated waste dumps
Topsoil and unsuitable materials that cannot be disposed of onsite shall be disposed of in gravel material borrow pits
1.2. Are the necessary skilled personnel available in the local market and where necessary will the contractor be able to bring in staff from outside the country?
Required trades are available within Zambia. Immigration rules allow for management staff and staff with specialist skills to be brought from outside the country
1.3. Do the works require the importation of any high value items of specialist plant? If so have alternatives that eliminate this need been considered?
None required
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1.4. Will double handling of materials be involved?
Steel pipes shall be stocked in available spaces along the pipeline routes and later transferred to the excavated trenches during installation
uPVC pipes, steel fittings and appurtenances shall be stockpiled at the contractor’s yard and delivered to site at time of installation to prevent issues of theft/ vandalism
Mass concrete shall be mixed at contractor’s batching plant and transferred to tank sites for in-situ construction
Earthworks materials and special bedding materials may be delivered directly to the point of use
1.5. Is there space for stockpiling of materials?
Space exists along the pipeline alignment for stringing of steel pipes and dumping of special bedding materials
1.6. Are utility locations accurately defined?
Overhead utilities (ZESCO and ZAMTEL) have been accurately surveyed and referenced on the drawings
Locations of existing underground cables and pipes have been obtained from the relevant utility providers and have been shown on the drawings
1.7. Has the need for utility relocation been identified and have the costs been defined with the appropriate utility?
Some existing water pipelines will need to be relocated
New power connections will be required at borehole sites in Ndeke/Vorna-Valley and Kwamwena areas
The estimated costs of relocation to be included in BoQs
Ensure costs for new power connections are included in the BoQ
1.8. Access consideration
1.8.1. Are personnel work areas easily accessible?
All structures and work areas are easily accessible
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1.8.2. Is there access for excavation plant?
Some sections are accessible only along the main roads servicing Mtendere and Kamanga. Several other streets within them have been reduced to narrow paths because of informal housing and market stalls constructed within the way-leaves. These have left limited space even to lay the pipelines except in the middle of the paths/roads
No access constraints in Kwamwena and Ndeke/Vorna-Valley
Will be addressed under the RAP consultancy
1.8.3. Is there access for haulage trucks to all areas they need to dump?
No access constraints
1.8.4. Are there traffic restrictions or congestion issues affecting site access?
Several streets in the inner parts of Mtendere and Kamanga have been reduced to narrow paths because of informal housing and market stalls constructed within the way-leaves
1.8.5. Are there measures available such as opening up temporary access routes that would considerably improve constructability?
Demolition of structures hindering access and constructability has been provided for
1.9. Will weather become a factor for the successful completion of the job?
Trenching and backfilling operations become an issue in the heavy rainfall months of December to March
Make allowances for reduced productivity in these months in the project timescale in the Contract Document
1.10. Efficiency of construction
1.10.1. Are there non-standard or complex methods of construction and could any of these be simplified?
No. Standard construction methods used
throughout
1.10.2. Has construction sequencing been considered in the design?
Yes. The boreholes are to be completed before the rising mains are constructed
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Checklist Item Constructability Further action required
1.11. Construction efficiency in specification
1.11.1. Are specifications adequate to meet functional requirements without being unnecessarily onerous which may introduce construction difficulties?
No non-standard specification provisions or tolerances have been introduced.
Further review of specification at 90% design
1.11.2. Have new items been introduced in the specifications/ method of measurement where standard items might suffice?
No
1.11.3. Do the specifications contain any restrictive clauses regarding source of material or equipment or manufacturing standard which may reduce options for competitive pricing?
All equipment and materials etc. are specified in terms of functional requirements
Where manufacturer’s names are used in the specifications or drawings, these are always suffixed with ‘or equivalent, or better’ to remove restriction whilst placing the emphasis on the contractor to demonstrate equality
1.12. Are pay items in the bid tabulation apparent in the specifications and in the drawings?
A standard specification and method of measurement is used (CESMM) and new items only introduced where the work items are not covered by the standard
Drawings need to contain cross references to pay items
Add cross references to drawings including tag numbers for mechanical equipment
Divide certain pay items in the BoQ such as concrete, earthworks etc. to indicate the location of the work
1.13. Are materials purchasing requirements simple to accurately extract from the Bill of Quantities?
CESMM bills use separate ‘supply’ and ‘install’ items for pipes and fittings
Mechanical components are individually itemised
Ensure ‘supply’ and ‘install’ quantities are consistent
Ensure all items of equipment are uniquely referenced in drawings, specifications and BoQ
Ensure drawings contain sufficient labelling and callouts to reference with items in the BoQ
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Checklist Item Constructability Further action required
2. EARTHWORKS
2.1. Has the design been earthworks balanced to reduce the need for imported materials?
Yes. However, some areas are rocky and will require imported material for backfilling.
2.2. Where imported materials are required is the specification appropriate to the requirement?
Yes. Details of quality of material for imported backfill are provided for in the specifications
3. PIPELAYING
3.1. Have the materials through which trenches are to be excavated been properly categorised?
Geotechnical investigations have characterised the materials throughout
3.2. Have any potential areas of ‘hard’ or intermediate excavation been identified and have sufficient quantities of such excavation been allowed for in the BoQ?
Extra-over excavation for areas with rock has been provided for in the BoQs
Extent and depth of intermediate excavation material to be marked on profile drawings and cross referenced to geotechnical investigations
3.3. Are trenches stable to the required digging depths or is shoring required. Do the specifications and drawings indicate the areas where shoring is required?
No deep trenches. Geotechnical investigations showed stable trench walls throughout the areas under LS3
The foundation depths for the new reservoirs in Kwamwena and Ndeke/Vorna-Valley are not deep as the geotechnical investigations revealed
3.4. Is groundwater likely to be encountered in any excavations?
None was detected within the influence zone of trenches during geotechnical investigations
Groundwater shall only be encountered in the borehole drilling sites of Ndeke/Vorna-Valley and Kwamwena
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3.5. Is specialist equipment required and if so have alternatives been considered to eliminate the need for it?
Use of concrete pump, cranes or other lifting mechanisms shall be necessary for the transfer of concrete for the construction of the elevated concrete tank in Ndeke/Vorna-Valley
Borehole drilling equipment (rig)
3.6. Is rock likely to be encountered and has provision been made in the designs?
Yes. Extra-over excavation for areas with rock has been provided for in the BoQs
3.7. Is rock blasting possible or are alternative measures for rock removal required?
Non-explosive rock blasting is recommended where works are close to built-up areas and near high-voltage ZESCO power lines
Specifications to clearly state where non-explosive rock blasting is required and what type is acceptable (e.g. fractac, gas system, etc.)
4. STRUCTURES
4.1. Are founding conditions suited to the structure foundation design?
Yes. The ground conditions are suitable for the construction of storage reservoirs, water kiosks and valve/washout chambers
4.2. Is sufficient working space available for structural works?
No constraints
5. MECHANICAL
5.1. Is mechanical equipment specified ‘standard’ and well supported with spares and technical knowledge?
All mechanical equipment is standard and regional availability has been checked
5.2. Is any long manufacturing lead time mechanical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment?
None
5.3. Is all mechanical equipment accessible for installation, maintenance and replacement?
Manufacturer’s minimum space requirements have been adhered to
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Checklist Item Constructability Further action required
5.4. Are the functional requirements of all mechanical equipment clearly indicated in the drawings or bills of quantities?
Drawings should include itemised descriptions and BoQ should include cross referencing to the specifications
Ensure cross referencing and detailed itemised descriptions of function and manufacturing requirements in specification
6. ELECTRICAL
6.1. Are electrical standards used in design appropriate to local practice?
IEE standards used together with local ZESCO regulations
6.2. Is electrical equipment specified ‘standard’ and well supported with spares and technical knowledge?
All electrical equipment types are locally supported
6.3. Is any long manufacturing lead time electrical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment?
No. borehole pumps are standard
6.4. Are electrical designs appropriate for tropical installation and have resilience to lightning strikes and power fluctuations been considered?
All electrical designs shall incorporate appropriate lightning protection
All designs are of a form commonly used in LWSC facilities. Robust starting equipment is specified
7. BUILDINGS
7.1. Are building materials specified readily available?
All are local stock items.
7.2. Are founding conditions suited to the building foundation design?
Geotechnical investigations have confirmed founding conditions.
8. TRAFFIC ACCOMMODATION
8.1. Is public access disrupted? There are several street crossings within project areas of LS3. Similarly, some of the internal streets of Mtendere and Kamanga are narrow and normal movement of public shall be disrupted during construction.
Ensure that dealing with access disruption is included in the specifications
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Checklist Item Constructability Further action required
8.2. Has access disruption to local businesses been considered?
Yes. Removal of market stalls and informal shops along the pipeline routes will be addressed in RAP.
Ensure inclusion in RAP
8.3. Has provision been made to ensure local people have access to their properties?
The specifications provide for temporary provision of access to people’s properties during construction
Ensure provision of temporary access during construction is included in the specifications
8.4. Is there provision for a traffic management plan?
Provision of ensuring control of traffic e.g. through placement of adequate signs and manual flagging is included in the specifications
Ensure provision of traffic management system is included in the specifications
9. SHUTDOWNS
9.1. Will provision of water/ sanitation services be disrupted?
Yes. Minor shut-downs will be necessary to allow for the interconnections of the new pipelines to existing pipelines. These shall be done by manually operating the sluice/gate valves that are nearest to the interconnection points.
Specifications to indicate maximum period of disruption of water supply
Specification/BoQ to include item for advertisement/ announcement of water supply disruption in local newspaper and on radio.
9.2. Is there provision for a shutdown management plan?
This will need to be agreed to with LWSC to minimise disruptions and coordinate between various work components
Specification to include requirements for shutdown management plan
10. RESETTLEMENT
10.1. Is sufficient survey data available to identify resettlement need?
Detailed topographical survey has picked up all walls and buildings near to pipelines
Land acquisition is necessary for the proposed borehole and tank sites in Ndeke/Vorna-Valley and Kwamwena as well as the water kiosks in Kamanga and Kwamwena
10.2. Has a resettlement corridor of impact been identified and constraints arising from it indicated in the drawings
The RCOI has been defined and some buildings and market stalls along the pipeline routes shall need to be removed to allow for the construction of the pipelines
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Checklist Item Constructability Further action required
10.3. Where the need for resettlement has been identified have design change options been considered to eliminate or reduce resettlement needs?
Yes, the selected pipeline routes have considered the best options where resettlement shall either be minimal or none. Similarly, in choosing the locations of the reservoirs and boreholes, sites that have been allocated for public use were considered as much as possible.
10.4. Is sufficient space available for working without disruption to buildings and walls?
No, some areas shall require some buildings, walls amongst other structures to be moved to allow for the construction of the pipelines.
Ensure inclusion in RAP
11. ENVIRONMENTAL
11.1. Have construction waste materials been identified and disposal methods specified?
Major arisings will be earth, rock, crushed concrete and building rubble. The former can be disposed of in borrow pits whilst the latter two can be incorporated into site filling
Minor arisings will be steel which can be recycled in Lusaka and timber which must be disposed of at landfill
Water arising from the borehole drilling process shall be directed to roadside drains.
Specification to include landfill requirements. BoQ item to be provided for Council landfill disposal costs.
11.2. Are any hazardous wastes expected and are safe disposal methods/ procedures specified?
None.
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Checklist Item Constructability Further action required
12. HEALTH AND SAFETY
12.1. As designed, do the construction methods have any intrinsic safety issues? Have these been addressed in the specification?
Open trenches are a safety hazard and will need to be properly fenced off and closed as soon as possible
Excavations are shallow and geotechnical investigations indicate stable trenching conditions
Caution must be taken while working at the elevated concrete tank in Kwamwena
The specifications need to contain detailed requirements for health and safety regarding trenches, dust, etc.
12.2. Are National Health and Safety regulations sufficiently rigorous when compared to international best practice or should additional HS clauses be included?
Final ESIA will cover health and safety and will propose additional specification clauses
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CSU15- Constructability Checklist
Checklist Item Constructability Further action required
1. GENERAL
1.1. Are areas available for:
1.1.1. Contractor’s camp and offices Suitable commercial rental properties are available within 5km of the project area
1.1.2. Materials stockpiles As above
1.1.3. Disposal of waste materials Non soil waste to be disposed in council designated waste dumps
Topsoil and unsuitable materials that cannot be disposed of on site shall be disposed of in gravel material borrow pits
1.2. Are the necessary skilled personnel available in the local market and where necessary will the contractor be able to bring in staff from outside the country.
Required trades are available within Zambia. Immigration rules allow for management staff and staff with specialist skills to be brought from outside the country.
1.3. Do the works require the importation of any high value items of specialist plant. If so have alternatives that eliminate this need been considered?
None required
1.4. Will double handling of materials be involved?
Force main pipe materials will need to be stockpiled at the contractor’s yard and delivered to site at time of installation to prevent issues of theft/ vandalism.
Earthworks materials and special bedding materials may be delivered directly to the point of use.
1.5. Is there space for stockpiling of materials?
Space exists along the pipeline alignment for stringing of pipes and dumping of special bedding materials
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1.6. Are utility locations accurately defined Overhead utilities (ZESCO) have been accurately surveyed and referenced on the drawings.
On the force main alignment a conflicting electricity cable has been reported by ZESCO during a site visit but is not yet reflected on the drawings.
No other buried services are known to exist after consultation with utility companies
In agreement with ZESCO the force main is to be removed from the South of their wayleave and installed on the north side. The ZESCO cable will be reflected in 90% design drawings.
1.7. Has the need for utility relocation been identified and have the costs been defined with the appropriate utility
No utility relocation required
1.8. Access consideration
1.8.1. Are personnel work areas easily accessible
All structures and work areas are easily accessible
1.8.2. Is there access for excavation plant
No access constraints
1.8.3. Is there access for haulage trucks to all areas they need to dump
No access constraints
1.8.4. Are there traffic restrictions or congestion issues affecting site access
None
1.8.5. Are there measures available such as opening up temporary access routes that would considerably improve constructability
Not Required
1.9. Will weather become a factor for the successful completion of the job
Trenching and backfilling operations become an issue in the heavy rainfall months of December to March
Make allowances for reduced productivity in these months in the project timescale in the Contract Document
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Checklist Item Constructability Further action required
1.10. Efficiency of construction
1.10.1. Are there non standard or complex methods of construction and could any of these be simplified
No. Standard construction methods used throughout.
Use of ‘elecrofusion’ HDPE pipe is not normal is Zambia. This is not considered a drawback however as skills and equipment are regionally available and ‘electrofusion’ has been chosen because it is an automated welding process requiring special equipment but less operator skill than ‘butt welding’ and offering better hydraulic and mechanical performance than flanged joints. It is also considered an appropriate new technology to introduce to LWSC and Zambia.
1.10.2. Has construction sequencing been considered in the design
Yes. New force main construction will be completed before works commence on the pump station, minimising over-pumping time.
An over-pumping connection point is designed as a permanent feature of the new force main
1.11. Construction efficiency in specification
1.11.1. Are specifications adequate to meet functional requirements without being unnecessarily onerous which may introduce construction difficulties.
No non standard specification provisions or tolerances have been introduced.
Further review of specification at 90% design
1.11.2. Have new items been introduced in the specifications/ method of measurement where standard items might suffice
No. BoQ preparation is by different staff to design preparation. Designers are only called on to provide new specification or MoM items where those preparing BoQs cannot find applicable standard items
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Checklist Item Constructability Further action required
1.11.3. Do the specifications contain any restrictive clauses regarding source of material or equipment or manufacturing standard which may reduce options for competitive pricing?
Restricting the source of pumps was considered but has been rejected based on comments from the Client. All pumps will be specified in terms of functional requirements only.
Manufacturer’s names, where used in the specifications or drawings, are always suffixed ‘or equal’ to remove restriction whilst placing the emphasis on the Contractor to demonstrate equality.
1.12. Are pay items in the bid tabulation apparent in the specifications and in the drawings
A standard specification and method of measurement is used (CESMM) and new items only introduced where the work items are not covered by the standard.
Drawings need to contain cross references to pay items.
Add cross references to drawings including tag numbers for mechanical equipment
Divide certain pay items in the BoQ such as concrete, earthworks etc. to indicate the location of the work
1.13. Are materials purchasing requirements simple to accurately extract from the Bill of Quantities
CESMM bills use separate ‘supply’ and ‘install’ items for pipes and fittings.
Mechanical and electrical components are individually itemised
Ensure ‘supply’ and ‘install’ quantities are consistent
Ensure all items of mechanical and electrical equipment are uniquely referenced in drawings, specifications and BoQ.
Ensure drawings contain sufficient labelling and callouts to reference with items in the BoQ
2. EARTHWORKS
2.1. Has the design been earthworks balanced to reduce the need for imported materials
No. There are no cut sources available within this component
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Checklist Item Constructability Further action required
2.2. Where imported materials are required is the specification appropriate to the requirement.
3. PIPELAYING
3.1. Have the materials through which trenches are to be excavated been properly categorised
Geotechnical investigations have characterised the materials throughout.
3.2. Have any potential areas of ‘hard’ or intermediate excavation been identified and have sufficient quantities of such excavation been allowed for in the BoQ
One area of ‘intermediate’ material has been identified and BoQ provision has been made
Extent and depth of intermediate excavation material to be marked on profile drawings cross referenced to geotechnical investigations.
3.3. Are trenches stable to the required digging depths or is shoring required. Do the specifications and drawings indicate the areas where shoring is required.
No deep trenches. Geotechnical investigations showed stable trench walls throughout this area.
3.4. Is groundwater likely to be encountered in any excavations
None was detected within the influence zone of trenches during geotechnical investigations.
3.5. Is specialist equipment required and if so have alternatives been considered to eliminate the need for it.
Electrofusion equipment is required for pipe jointing. The equipment is specialist but relatively inexpensive and justified by the improved final product.
3.6. Is rock likely to be encountered and has provision been made in the designs
3.7. Is rock blasting possible or are alternative measures for rock removal required
4. STRUCTURES
4.1. Are founding conditions suited to the structure foundation design
No new structure foundations required
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4.2. Is sufficient working space available for structural works
No constraints
5. MECHANICAL
5.1. Is mechanical equipment specified ‘standard’ and well supported with spares and technical knowledge.
All mechanical equipment is standard and regional availability has been checked
5.2. Is any long manufacturing lead time mechanical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment.
None
5.3. Is all mechanical equipment accessible for installation, maintenance and replacement.
Manufacturer’s minimum space requirements have been adhered to
5.4. Are the functional requirements of all mechanical equipment clearly indicated in the drawings or bills of quantities.
Drawings should include part numbers cross referencing detailed descriptions in the specification
Ensure cross referencing and detailed itemised descriptions of function and manufacturing requirements in specification.
6. ELECTRICAL
6.1. Are electrical standards used in design appropriate to local practice.
IEE standards used
6.2. Is electrical equipment specified ‘standard’ and well supported with spares and technical knowledge.
All electrical equipment types are locally supported
6.3. Is any long manufacturing lead time electrical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment.
None
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6.4. Are electrical designs appropriate for tropical installation and have resilience to lightning strikes and power fluctuations been considered
All electrical designs shall incorporate appropriate lightning protection
All designs are of a form commonly used in LWSC facilities. Robust DOL starting equipment is specified
7. BUILDINGS
7.1. Are building materials specified readily available
All are local stock items
7.2. Are founding conditions suited to the building foundation design
Geotechnical investigations have confirmed founding conditions
8. TRAFFIC ACCOMMODATION
8.1. Is public access disrupted. No road crossings or disruption to public traffic either motorised or pedestrian.
8.2. Has access disruption to local businesses been considered
None identified along the pipeline route
8.3. Has provision been made to ensure local people have access to their properties
No property access affected
8.4. Is there provision for a traffic management plan
Not required
9. SHUTDOWNS
9.1. Will provision of water/ sanitation services be disrupted?
No. Over-pumping will ensure uninterrupted function
9.2. Is there provision for a shutdown management plan?
This will need to be agreed to with LWSC to minimise disruptions and coordinate between various work components
Specification to include requirements for shutdown management plan.
10. RESETTLEMENT
10.1. Is sufficient survey data available to identify resettlement need?
Detailed topo survey has picked up all walls and buildings near to pipelines
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10.2. Has a resettlement corridor of impact been identified and constraints arising from it indicated in the drawings
No works are constrained by resettlement needs.
10.3. Where the need for resettlement has been identified have design change options been considered to eliminate or reduce resettlement needs
No resettlement required
10.4. Is sufficient space available for working without disruption to buildings and walls
Yes, in all areas.
11. ENVIRONMENTAL
11.1. Have construction waste materials been identified and disposal methods specified
Major arisings will be earth, crushed concrete and building rubble. The former can be disposed of in borrow pits whilst the latter two can be incorporated into site filling.
Minor arisings will be steel which can be recycled in Lusaka and timber which must be disposed of at landfill.
Specification to include landfill requirements. BoQ item to be provided for council landfill disposal costs.
11.2. Are any hazardous wastes expected and are safe disposal methods/ procedures specified.
Some sewage sludge will arise which will have to be taken to a licensed landfill site
Specification to include landfill requirements. BoQ item to be provided for council landfill disposal costs.
12. HEALTH AND SAFETY
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Checklist Item Constructability Further action required
12.1. As designed, do the construction methods have any intrinsic safety issues. Have these been addressed in the specification.
Some pipelaying works need to be carried out parallel to power lines. Discussions with ZESCO have indicated that these lines have redundancy and may be shut down to accommodate the works. Otherwise hand excavation will be specified.
Excavations are shallow and geotechnical investigations indicate stable trenching conditions.
The specifications need to contain detailed requirements for all works parallel to power lines.
12.2. Are National Health and Safety regulations sufficiently rigourous when compared to international best practice or should additional HS clauses be included.
Final ESIA will cover health and safety and will propose additional specification clauses
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CSU15- Constructability Checklist 3 – Function
Checklist Item Constructability Further action required by 90% Design Stage
13. GENERAL
13.1. Are areas available for:
13.1.1. Contractor’s camp and offices Suitable commercial rental properties are available within 5km of the project area
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CSU-44 Mtendere Sewershed Expansion Constructability Checklist
Checklist Item Constructability Further action required
1. GENERAL
1.1. Are areas available for:
1.1.1. Contractor’s camp and offices Suitable commercial rental properties are available within 5 km of the project area
1.1.2. Materials stockpiles As above
1.1.3. Disposal of waste materials Most arisings from excavation will be returned to the trenches.
Any unsuitable materials will be hauled to the selected materials borrow pits.
1.2. Are the necessary skilled personnel available in the local market and where necessary will the contractor be able to bring in staff from outside the country?
Required trades are available within Zambia. Immigration rules allow for management staff and staff with specialist skills to be brought from outside the country
1.3. Do the works require the importation of any high value items of specialist plant? If so have alternatives that eliminate this need been considered?
The narrow working width will require the use of short overhang excavators but these are readily available and not particularly high value items. TLB excavators could be used as an alternative but will offer lower productivity.
1.4. Will double handling of materials be involved?
Pipes will have to be stockpiled at the contractor’s yard before being brought to site for installation. Theft of small diameter pipes means that on site stockpiling will not be possible.
Earthworks materials and special bedding materials may be delivered directly to the point of use
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Checklist Item Constructability Further action required
1.5. Is there space for stockpiling of materials?
Space exists along the pipeline alignment for stringing of pipes and dumping of special bedding materials
1.6. Are utility locations accurately defined?
Locations of existing underground cables and pipes have been obtained from the relevant utility providers and are shown on the drawings. However plotting accuracy of these is poor and hand excavation will be required in locations where services are expected to exist.
1.7. Has the need for utility relocation been identified and have the costs been defined with the appropriate utility?
No services relocation needs have been identified
The estimated costs of relocation to be included in BoQs
1.8. Access consideration
1.8.1. Are personnel work areas easily accessible?
All structures and work areas are easily accessible
1.8.2. Is there access for excavation plant?
Access widths are narrow, generally around 3.5m. Thus while all trucks and plant will be able to access the works, short overhang excavators, able to swing in such confined spaces, are expected to be used.
1.8.3. Is there access for haulage trucks to all areas they need to dump?
No access constraints
1.8.4. Are there traffic restrictions or congestion issues affecting site access?
The area is served by several main access roads which are largely uncongested outside of morning and evening rush hour.
Will be addressed under the RAP consultancy
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1.8.5. Are there measures available such as opening up temporary access routes that would considerably improve constructability?
Not required
1.9. Will weather become a factor for the successful completion of the job?
Trenching and backfilling operations become an issue in the heavy rainfall months of December to March
Make allowances for reduced productivity in these months in the project timescale
1.10. Efficiency of construction
1.10.1. Are there non-standard or complex methods of construction and could any of these be simplified?
Use of pipe jacking is proposed for one sewer crossing of the Great East Road. The method is required as trenching will disrupt one of the busiest arterial roads as well as endangering multiple key services including power and data trunk lines.
1.10.2. Has construction sequencing been considered in the design?
No constraints.
1.11. Construction efficiency in specification
1.11.1. Are specifications adequate to meet functional requirements without being unnecessarily onerous which may introduce construction difficulties?
No non-standard specification provisions or tolerances have been introduced.
Further review of specification at 90% design
1.11.2. Have new items been introduced in the specifications/ method of measurement where standard items might suffice?
No
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Checklist Item Constructability Further action required
1.11.3. Do the specifications contain any restrictive clauses regarding source of material or equipment or manufacturing standard which may reduce options for competitive pricing?
All equipment and materials etc. will be specified in terms of functional requirements only
Where manufacturer’s names are used in the specifications or drawings, these are always suffixed with ‘or equivalent, or better’ to remove restriction whilst placing the emphasis on the contractor to demonstrate equality
1.12. Are pay items in the bid tabulation apparent in the specifications and in the drawings?
A standard specification and method of measurement is used (CESMM) and new items only introduced where the work items are not covered by the standard
Drawings need to contain cross references to pay items
Add cross references to drawings including tag numbers for mechanical equipment
Divide certain pay items in the BoQ such as concrete, earthworks etc. to indicate the location of the work
1.13. Are materials purchasing requirements simple to accurately extract from the Bill of Quantities?
CESMM bills use separate ‘supply’ and ‘install’ items for pipes and fittings
Mechanical components are individually itemised
Ensure ‘supply’ and ‘install’ quantities are consistent
Ensure all items of equipment are uniquely referenced in drawings, specifications and BoQ
Ensure drawings contain sufficient labelling and callouts to reference with items in the BoQ
2. EARTHWORKS
2.1. Has the design been earthworks balanced to reduce the need for imported materials?
No bulk earthworks required
2.2. Where imported materials are required is the specification appropriate to the requirement?
Yes. Details of quality of material for imported backfill are provided for in the specifications.
3. PIPELAYING
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Checklist Item Constructability Further action required
3.1. Have the materials through which trenches are to be excavated been properly categorised?
Geotechnical investigations have characterised the materials throughout.
3.2. Have any potential areas of ‘hard’ or intermediate excavation been identified and have sufficient quantities of such excavation been allowed for in the BoQ?
Extra-over excavation for areas with rock has been provided for in the BoQs with nominal quantities but no rock was identified in any trial hole or SPT test carried out in Mtendere
Extent and depth of intermediate excavation material to be marked on profile drawings cross referenced to geotechnical investigations.
3.3. Are trenches stable to the required digging depths or is shoring required. Do the specifications and drawings indicate the areas where shoring is required?
Deep trenches (>2m) are required for various sections of sewer line. Shoring of these will be required whenever people must enter the trench to work.
3.4. Is groundwater likely to be encountered in any excavations?
Groundwater is expected to be encountered in the deeper sewer lines and especially in the months just following rainy season but only at depths >1m. Working uphill in trench excavations will be sufficient to keep them dewatered.
3.5. Is specialist equipment required and if so have alternatives been considered to eliminate the need for it?
Short overhand excavators are expected to be used for trenching in confined areas.
3.6. Is rock likely to be encountered and has provision been made in the designs?
No rock was encountered during geotechnical investigations.
3.7. Is rock blasting possible or are alternative measures for rock removal required?
Rock is not expected but blasting would not be allowed in these built up areas.
Specifications to include acceptable rock breaking measures
4. STRUCTURES
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Checklist Item Constructability Further action required
4.1. Are founding conditions suited to the structure foundation design?
Yes. Ground conditions have been confirmed from geotechnical investigations
4.2. Is sufficient working space available for structural works?
No constraints
5. MECHANICAL
5.1. Is mechanical equipment specified ‘standard’ and well supported with spares and technical knowledge?
All mechanical equipment is standard and regional availability has been checked
5.2. Is any long manufacturing lead time mechanical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment?
None
5.3. Is all mechanical equipment accessible for installation, maintenance and replacement?
Manufacturer’s minimum space requirements have been adhered to.
5.4. Are the functional requirements of all mechanical equipment clearly indicated in the drawings or bills of quantities?
Drawings should include part numbers cross referencing detailed descriptions in the specification.
Ensure cross referencing and detailed itemised descriptions of function and manufacturing requirements in specification.
6. ELECTRICAL
6.1. Are electrical standards used in design appropriate to local practice?
IEE standards used
6.2. Is electrical equipment specified ‘standard’ and well supported with spares and technical knowledge?
All electrical equipment types are locally supported
6.3. Is any long manufacturing lead time electrical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment?
None
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Checklist Item Constructability Further action required
6.4. Are electrical designs appropriate for tropical installation and have resilience to lightning strikes and power fluctuations been considered?
All electrical designs shall incorporate appropriate lightning protection
All designs are of a form commonly used in LWSC facilities.
7. BUILDINGS
7.1. Are building materials specified readily available?
All are local stock items.
7.2. Are founding conditions suited to the building foundation design?
Geotechnical investigations have confirmed founding conditions.
8. TRAFFIC ACCOMMODATION
8.1. Is public access disrupted? There are numerous road crossings and trenches in roads within the Mtendere Township area.
Specifications will limit the length of open trench allowed to minimise disruption to traffic but there will be areas cut off from vehicle access
8.2. Has access disruption to local businesses been considered?
Yes. Removal of market stalls and informal shops along the pipeline routes will be addressed in RAP.
Ensure inclusion in RAP
8.3. Has provision been made to ensure local people have access to their properties?
The specifications provide for temporary provision of access to people’s properties during construction
Ensure provision of temporary access during construction is included in the specifications
8.4. Is there provision for a traffic management plan?
Provision of ensuring control of traffic e.g. through placement of adequate signs and manual flagging is included in the specifications
Ensure provision of traffic management system is included in the specifications
9. SHUTDOWNS
9.1. Will provision of water/ sanitation services be disrupted?
No. The existing area has no sanitation services so there will be no disruption.
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Checklist Item Constructability Further action required
9.2. Is there provision for a shutdown management plan?
Sewer tie ins with the CSU-4 Kaunda Square interceptor will need to be co-ordinated with LWSC
10. RESETTLEMENT
10.1. Is sufficient survey data available to identify resettlement need?
Detailed topographical survey has picked up all walls and buildings near to pipelines.
10.2. Has a resettlement corridor of impact been identified and constraints arising from it indicated in the drawings
The RCOI has been defined and some market stalls along the pipeline route shall need to be removed to allow for the construction of the pipeline.
10.3. Where the need for resettlement has been identified have design change options been considered to eliminate or reduce resettlement needs?
Impact has been minimised by specifying a narrow (3.5m) available working corridor.
10.4. Is sufficient space available for working without disruption to buildings and walls?
No, some areas shall require buildings, and walls which are in the road wayleaves to be removed to allow for the construction of the pipelines
Ensure inclusion in RAP
11. ENVIRONMENTAL
11.1. Have construction waste materials been identified and disposal methods specified?
Major arisings will be earth, and building rubble. The former can be disposed of on site or in borrow pits whilst the latter can be incorporated into site filling.
Specification to include landfill requirements. BoQ item to be provided for Council landfill disposal costs.
11.2. Are any hazardous wastes expected and are safe disposal methods/ procedures specified?
None
12. HEALTH AND SAFETY
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Checklist Item Constructability Further action required
12.1. As designed, do the construction methods have any intrinsic safety issues? Have these been addressed in the specification?
Pipelaying in deep trenches will require shoring of the trenches.
Geotechnical investigations indicate stable trenching conditions
12.2. Are National Health and Safety regulations sufficiently rigorous when compared to international best practice or should additional HS clauses be included?
Final ESIA will cover health and safety and will propose additional specification clauses
Include relevant HS clauses
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CSU-4 Kaunda Square Interceptor Constructability Checklist
Checklist Item Constructability Further action required
1. GENERAL
1.1. Are areas available for:
1.1.1. Contractor’s camp and offices Suitable commercial rental properties are available within 5 km of the project area
1.1.2. Materials stockpiles As above
1.1.3. Disposal of waste materials Most arisings from excavation will be returned to the trenches.
Any unsuitable materials will be hauled to the selected materials borrow pits.
1.2. Are the necessary skilled personnel available in the local market and where necessary will the contractor be able to bring in staff from outside the country?
Required trades are available within Zambia. Immigration rules allow for management staff and staff with specialist skills to be brought from outside the country
1.3. Do the works require the importation of any high value items of specialist plant? If so have alternatives that eliminate this need been considered?
None
1.4. Will double handling of materials be involved?
Pipes will have to be stockpiled at the contractor’s yard before being brought to site for installation. Some stringing of pipes along the proposed route will be possible with adequate security
Earthworks materials and special bedding materials may be delivered directly to the point of use
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Checklist Item Constructability Further action required
1.5. Is there space for stockpiling of materials?
Space exists along the pipeline alignment for stringing of pipes and dumping of special bedding materials
1.6. Are utility locations accurately defined?
Locations of existing underground cables and pipes have been obtained from the relevant utility providers and are shown on the drawings. However plotting accuracy of these is poor and hand excavation will be required in locations where services are expected to exist.
1.7. Has the need for utility relocation been identified and have the costs been defined with the appropriate utility?
There is a need to relocate certain ZESO power infrastructure which has been indicated to ZESCO. Quotations will be obtained.
ZESCO quotation values will be included in the BoQ
1.8. Access consideration
1.8.1. Are personnel work areas easily accessible?
All structures and work areas are easily accessible
1.8.2. Is there access for excavation plant?
Yes
1.8.3. Is there access for haulage trucks to all areas they need to dump?
No access constraints
1.8.4. Are there traffic restrictions or congestion issues affecting site access?
The area is served by a main road which is largely uncongested outside of morning and evening rush hour.
1.8.5. Are there measures available such as opening up temporary access routes that would considerably improve constructability?
Not required
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Checklist Item Constructability Further action required
1.9. Will weather become a factor for the successful completion of the job?
Trenching and backfilling operations become an issue in the heavy rainfall months of December to March
Make allowances for reduced productivity in these months in the project timescale
1.10. Efficiency of construction
1.10.1. Are there non-standard or complex methods of construction and could any of these be simplified?
None
1.10.2. Has construction sequencing been considered in the design?
No constraints.
1.11. Construction efficiency in specification
1.11.1. Are specifications adequate to meet functional requirements without being unnecessarily onerous which may introduce construction difficulties?
No non-standard specification provisions or tolerances have been introduced.
Further review of specification at 90% design
1.11.2. Have new items been introduced in the specifications/ method of measurement where standard items might suffice?
No
1.11.3. Do the specifications contain any restrictive clauses regarding source of material or equipment or manufacturing standard which may reduce options for competitive pricing?
All equipment and materials etc. will be specified in terms of functional requirements only
Where manufacturer’s names are used in the specifications or drawings, these are always suffixed with ‘or equivalent, or better’ to remove restriction whilst placing the emphasis on the contractor to demonstrate equality
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Checklist Item Constructability Further action required
1.12. Are pay items in the bid tabulation apparent in the specifications and in the drawings?
A standard specification and method of measurement is used (CESMM) and new items only introduced where the work items are not covered by the standard
Drawings need to contain cross references to pay items
Add cross references to drawings including tag numbers for mechanical equipment
Divide certain pay items in the BoQ such as concrete, earthworks etc. to indicate the location of the work
1.13. Are materials purchasing requirements simple to accurately extract from the Bill of Quantities?
CESMM bills use separate ‘supply’ and ‘install’ items for pipes and fittings
Mechanical components are individually itemised
Ensure ‘supply’ and ‘install’ quantities are consistent
Ensure all items of equipment are uniquely referenced in drawings, specifications and BoQ
Ensure drawings contain sufficient labelling and callouts to reference with items in the BoQ
2. EARTHWORKS
2.1. Has the design been earthworks balanced to reduce the need for imported materials?
No bulk earthworks required.
2.2. Where imported materials are required is the specification appropriate to the requirement?
Yes. Details of quality of material for imported backfill are provided for in the specifications.
3. PIPELAYING
3.1. Have the materials through which trenches are to be excavated been properly categorised?
Geotechnical investigations have characterised the materials throughout.
3.2. Have any potential areas of ‘hard’ or intermediate excavation been identified and have sufficient quantities of such excavation been allowed for in the BoQ?
Geotechnical investigations identified no areas of rock along this pipeline route. Most of the pipe length is installed as a replacement of an existing pipe with matching invert levels.
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Checklist Item Constructability Further action required
3.3. Are trenches stable to the required digging depths or is shoring required. Do the specifications and drawings indicate the areas where shoring is required?
Deep trenches (>2m) are required for various sections of sewer line. Shoring of these will be required whenever people must enter the trench to work.
3.4. Is groundwater likely to be encountered in any excavations?
Groundwater is expected to be encountered in the deeper sewer lines and especially in the months just following rainy season but only at depths >1m. Working uphill in trench excavations will be sufficient to keep them dewatered.
3.5. Is specialist equipment required and if so have alternatives been considered to eliminate the need for it?
None
3.6. Is rock likely to be encountered and has provision been made in the designs?
No rock was encountered during geotechnical investigations.
3.7. Is rock blasting possible or are alternative measures for rock removal required?
Rock is not expected but blasting would not be allowed in these built up areas.
Specifications to include acceptable rock breaking measures
4. STRUCTURES
4.1. Are founding conditions suited to the structure foundation design?
No structures
4.2. Is sufficient working space available for structural works?
No constraints
5. MECHANICAL
5.1. Is mechanical equipment specified ‘standard’ and well supported with spares and technical knowledge?
Not applicable
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Checklist Item Constructability Further action required
5.2. Is any long manufacturing lead time mechanical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment?
None
5.3. Is all mechanical equipment accessible for installation, maintenance and replacement?
Not applicable
5.4. Are the functional requirements of all mechanical equipment clearly indicated in the drawings or bills of quantities?
Not applicable
6. ELECTRICAL
6.1. Are electrical standards used in design appropriate to local practice?
Not applicable
6.2. Is electrical equipment specified ‘standard’ and well supported with spares and technical knowledge?
Not applicable
6.3. Is any long manufacturing lead time electrical equipment specified and could this be replaced by more standard ‘off the shelf’ equipment?
Not applicable
6.4. Are electrical designs appropriate for tropical installation and have resilience to lightning strikes and power fluctuations been considered?
Not applicable
7. BUILDINGS
7.1. Are building materials specified readily available?
Not applicable
7.2. Are founding conditions suited to the building foundation design?
Not applicable
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Checklist Item Constructability Further action required
8. TRAFFIC ACCOMMODATION
8.1. Is public access disrupted? There are numerous road crossings and along the pipe route.
Specifications will limit the length of open trench allowed to minimise disruption to traffic but there will be areas cut off from vehicle access.
Diversions will and alternate routes will be required where public roads are to be cut.
8.2. Has access disruption to local businesses been considered?
Yes. Removal of market stalls and informal shops along the pipeline routes will be addressed in RAP.
Ensure inclusion in RAP
8.3. Has provision been made to ensure local people have access to their properties?
The specifications provide for temporary provision of access to people’s properties during construction
Ensure provision of temporary access during construction is included in the specifications
8.4. Is there provision for a traffic management plan?
Provision of ensuring control of traffic e.g. through placement of adequate signs and manual flagging is included in the specifications
Ensure provision of traffic management system is included in the specifications
9. SHUTDOWNS
9.1. Will provision of water/ sanitation services be disrupted?
No. Over-pumping will be put in place to handle sewage flows during pipe replacement.
9.2. Is there provision for a shutdown management plan?
The tie in of the sewer to the Kaunda Square ponds will need to be co-ordinated with that contractor.
10. RESETTLEMENT
10.1. Is sufficient survey data available to identify resettlement need?
Detailed topographical survey has picked up all walls and buildings near to pipelines.
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Checklist Item Constructability Further action required
10.2. Has a resettlement corridor of impact been identified and constraints arising from it indicated in the drawings
The RCOI has been defined and some properties encroaching on the pipeline shall need to be removed to allow for the construction of the pipeline.
10.3. Where the need for resettlement has been identified have design change options been considered to eliminate or reduce resettlement needs?
Impact has been minimised by specifying a narrow (3.5m) available working corridor.
One length of pipe has been realigned to minimise interference with existing properties
10.4. Is sufficient space available for working without disruption to buildings and walls?
No, some areas shall require buildings, and walls which are in the road wayleaves to be removed to allow for the construction of the pipelines
Ensure inclusion in RAP
11. ENVIRONMENTAL
11.1. Have construction waste materials been identified and disposal methods specified?
Major arisings will be earth, and building rubble. The former can be disposed of on site or in borrow pits whilst the latter can be incorporated into site filling.
Old pipe materials are to be excavated. These will be sewage contaminated and will need to be disposed of in landfill.
Specification to include landfill requirements. BoQ item to be provided for Council landfill disposal costs.
11.2. Are any hazardous wastes expected and are safe disposal methods/ procedures specified?
Old sewage pipes will need to be properly disposed of in landfill.
12. HEALTH AND SAFETY
12.1. As designed, do the construction methods have any intrinsic safety issues? Have these been addressed in the specification?
Pipelaying in deep trenches will require shoring of the trenches.
Geotechnical investigations indicate stable trenching conditions
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Checklist Item Constructability Further action required
12.2. Are National Health and Safety regulations sufficiently rigorous when compared to international best practice or should additional HS clauses be included?
Final ESIA will cover health and safety and will propose additional specification clauses
Include relevant HS clauses
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TU-5 & TE-3- Constructability Checklist
Checklist Item Constructability Further action required
1. GENERAL
1.1. Are areas available for:
1.1.1. Contractor’s camp and offices Suitable commercial rental properties are available within 5km of the project area
1.1.2. Materials stockpiles As above
1.1.3. Disposal of waste materials Non soil waste to be disposed in council designated waste dumps
Topsoil and unsuitable materials that cannot be disposed of on site shall be disposed of in gravel material borrow pits
1.2. Are the necessary skilled personnel available in the local market and where necessary will the contractor be able to bring in staff from outside the country.
Required trades are available within Zambia. Immigration rules allow for management staff and staff with specialist skills to be brought from outside the country.
1.3. Do the works require the importation of any high value items of specialist plant. If so have alternatives that eliminate this need been considered?
A floating dredge is required which will form part of LWSCs future maintenance equipment to allow de-silting of other ponds and as such is essential.
1.4. Will double handling of materials be involved?
Inter-pond connecting pipe materials, pond liner, reinforcement will need to be stockpiled at the contractor’s yard and delivered to site at time of installation to prevent issues of theft/ vandalism.
Earthworks materials and special bedding materials may be delivered directly to the point of use.
1.5. Is there space for stockpiling of materials?
Space exists on the site for stockpiling of materials
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Checklist Item Constructability Further action required
1.6. Are utility locations accurately defined No utility locations
1.7. Access consideration
1.7.1. Are personnel work areas easily accessible
All structures and work areas are easily accessible
1.7.2. Is there access for excavation plant
No access constraints
1.7.3. Is there access for haulage trucks to all areas they need to dump
No access constraints
1.7.4. Are there traffic restrictions or congestion issues affecting site access
None
1.7.5. Are there measures available such as opening up temporary access routes that would considerably improve constructability
Yes, divert the main road leading to the Kwamwena Housing Estate and Mutumbi Cemetery
1.8. Will weather become a factor for the successful completion of the job
Excavations and backfilling operations become an issue in the heavy rainfall months of December to March
Make allowances for reduced productivity in these months in the project timescale in the Contract Document
1.9. Efficiency of construction
1.9.1. Are there non standard or complex methods of construction and could any of these be simplified
No. Standard construction methods used throughout.
1.9.2. Has construction sequencing been considered in the design
Yes. Construction of Extension area will be completed before works commence on the upgrade area, minimising flow diversion.
A by-pass line is designed as a permanent feature of the new pond system.
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Checklist Item Constructability Further action required
1.10. Construction efficiency in specification
1.10.1. Are specifications adequate to meet functional requirements without being unnecessarily onerous which may introduce construction difficulties?
No non standard specification provisions or tolerances have been introduced.
Further review of specification at 90% design
1.10.2. Have new items been introduced in the specifications/ method of measurement where standard items might suffice
No. BoQ preparation is by different staff to design preparation. Designers are only called on to provide new specification or MoM items where those preparing BoQs cannot find applicable standard items
1.10.3. Do the specifications contain any restrictive clauses regarding source of material or equipment or manufacturing standard which may reduce options for competitive pricing?
Restricting the source of pumps was considered but has been rejected based on comments from the Client. All pumps will be specified in terms of functional requirements only.
Manufacturer’s names, where used in the specifications or drawings, are always suffixed ‘or equal’ to remove restriction whilst placing the emphasis on the Contractor to demonstrate equality.
1.11. Are pay items in the bid tabulation apparent in the specifications and in the drawings
A standard specification and method of measurement is used (CESMM) and new items only introduced where the work items are not covered by the standard.
Drawings need to contain cross references to pay items.
Add cross references to drawings including tag numbers for mechanical equipment
Divide certain pay items in the BoQ such as concrete, earthworks etc. to indicate the location of the work
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Checklist Item Constructability Further action required
1.12. Are materials purchasing requirements simple to accurately extract from the Bill of Quantities
CESMM bills use separate ‘supply’ and ‘install’ items for pipes and fittings.
Mechanical and electrical components are individually itemised
Ensure ‘supply’ and ‘install’ quantities are consistent
Ensure all items of mechanical and electrical equipment are uniquely referenced in drawings, specifications and BoQ.
Ensure drawings contain sufficient labelling and callouts to reference with items in the BoQ
2. EARTHWORKS
2.1. Has the design been earthworks balanced to reduce the need for imported materials
No, because of trying to utilise the existing foot print.
2.2. Where imported materials are required is the specification appropriate to the requirement.
Yes
3. PIPELAYING
3.1. Have the materials through which trenches are to be excavated been properly categorised
Geotechnical investigations have characterised the materials throughout.
3.2. Have any potential areas of ‘hard’ or intermediate excavation been identified and have sufficient quantities of such excavation been allowed for in the BoQ
One area of ‘intermediate’ material has been identified and BoQ provision has been made
Extent and depth of intermediate excavation material to be marked on profile drawings cross referenced to geotechnical investigations.
3.3. Is groundwater likely to be encountered in any excavations
Yes, as was observed during the geotechnical investigations stage.
3.4. Is specialist equipment required and if so have alternatives been considered to eliminate the need for it.
Electrofusion equipment is required for lining jointing. The equipment is specialist but relatively inexpensive and justified by the improved final product.
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Checklist Item Constructability Further action required
3.5. Is rock likely to be encountered and has provision been made in the designs
Non was encountered during geotechnical investigations
3.6. Is rock blasting possible or are alternative measures for rock removal required
No
4. STRUCTURES
4.1. Are founding conditions suited to the structure foundation design
Yes
4.2. Is sufficient working space available for structural works
No constraints
5. MECHANICAL
6. ELECTRICAL
6.1. Are electrical standards used in design appropriate to local practice?
IEE standards used
7. BUILDINGS
7.1. Are building materials specified readily available
All are local stock items
7.2. Are founding conditions suited to the building foundation design
Geotechnical investigations have confirmed founding conditions
8. TRAFFIC ACCOMMODATION
8.1. Is public access disrupted? Yes, an alternative route will be provided and maintained according to stated regulations.
8.2. Has access disruption to local businesses been considered
Yes
8.3. Has provision been made to ensure local people have access to their properties
Yes Land requisition issues are still on- going
8.4. Is there provision for a traffic management plan
Not applicable
9. RESETTLEMENT
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Checklist Item Constructability Further action required
9.1. Is sufficient survey data available to identify resettlement need?
Detailed topo survey has picked up all structures within the proposed land area
9.2. Where the need for resettlement has been identified have design change options been considered to eliminate or reduce resettlement needs
Resttlement needs have been minimised but significant land take is still required.
9.3. Is sufficient space available for working without disruption to buildings and walls
Yes.
10. ENVIRONMENTAL
10.1. Have construction waste materials been identified and disposal methods specified
Major waste materials will be earth and rubble from existing concrete works. The former can be disposed of in borrow pits whilst the latter can be incorporated into embankment filling.
Specification to include landfill requirements. BoQ item to be provided for council landfill disposal costs.
10.2. Are any hazardous wastes expected and are safe disposal methods/ procedures specified.
Some sewage sludge will arise which will have to be taken to a licensed landfill site
Specification to include landfill requirements. BoQ item to be provided for council landfill disposal costs.
11. HEALTH AND SAFETY
11.1. As designed, do the construction methods have any intrinsic safety issues? Have these been addressed in the specification.
Some desludging works need to be carried out on the existing ponds. Sludge handling from the ponds needs special attention as it will be packed in plastics and then disposed of to a designated waste disposal site.
Excavations are about 5 m deep. Geotechnical investigations indicate stable soil and maintaining a side slope of 1:2.
Specification to include landfill requirements. BoQ item to be provided for council landfill disposal costs.
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Checklist Item Constructability Further action required
11.2. Are National Health and Safety regulations sufficiently rigorous when compared to international best practice or should additional HS clauses be included.
Final ESIA will cover health and safety and will propose additional specification clauses
TU-5 & TE-3- Constructability Checklist 2 – Function
Checklist Item Constructability Further action required
12. GENERAL
12.1. Are areas available for:
12.1.1. Contractor’s camp and offices Suitable commercial rental properties are available within 5km of the project area
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Lu
saka W
ate
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pp
ly, S
an
itatio
n a
nd
Dra
inag
e (L
WS
SD
) Pro
ject
Deta
iled E
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ender D
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ents
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r Supp
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nd S
an
itatio
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AN
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An
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Work
Pro
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IDTask N
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Duration
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JF
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JF
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Half 1
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Rolled U
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Rolled U
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Project Sum
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Group B
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Deadline
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Project: CP
4-Programm
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Date: Fri 09/11/12
Constructability R
eport A
nnex II - Work P
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