extendend aeration waste water treatment plant …chuka.ac.ke/advert 17/srp (extended aeration...
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CHUKA UNIVERSITY
PROPOSED SCIENCE RESEARCH
PARK – PHASE 1
EXTENDEND AERATION WASTE WATER TREATMENT PLANT (EATP)
Contract Number: CU/OPNT/53/2016-2017
Consulting Architects Consulting structural/ Civil Engineers
Conte Design Multiscope Consulting Engineers
Email: [email protected] Email: [email protected]
Consulting Quantity Surveyor Consulting Elect. &Mech. Engineers
Ecospace Consultants Mecoy Consultants LTD
Email: [email protected] Email: [email protected]
Issued by:
VICE CHANCELLOR
CHUKA UNIVERSITY
P.O. BOX 109 - 60400
CHUKA
April 2017
CHUKA UNIVERSITY
DECEMBER, 2016 Page i
TABLES OF CONTENTS
FORM OF BID, AGREEMENT AND QUALIFICATION INFORMATION ........................... 1
Bid Submission Form ....................................................................................................................2
CONDITIONS OF CONTRACT ...................................................................................................... 9
General Conditions of Contract ..................................................................................................9
Special Conditions of Contract ..................................................................................................13
Sub clause 1.1 Definitions ................................................................................................................ 13
WASTER WATER TREATMENT PLANT EVALUATION CRITERIA ................................... 35
LIST OF DRAWINGS ....................................................................................................................... 36
BILL OF QUANTITIES .................................................................................................................... 39
PREAMBLE TO THE BILLS OF QUANTITIES .......................................................................... 40
TECHNICAL DIRECTIONS .......................................................................................................... 40
TECHNICAL SPECIFICATIONS .............................................................................................44
DESIGN CALCULATIONS .......................................................................................................59
LIST OF FIGURES
Figure 1-1: Location Plan for the Sewer Reticulation and the Extended Aeration Waste Water Treatment Plant (Package). .............................. 38
CHUKA UNIVERSITY
DECEMBER, 2016 Page 1
FORM OF BID, AGREEMENT AND QUALIFICATION INFORMATION
Bidder Information Form
[The Bidder shall fill in this Form in accordance with the instructions indicated below. No alterations
to its format shall be permitted and no substitutions shall be accepted.]
1. Bidder’s Legal Name
2. In case of JV, legal name of each party:
3. Bidder’s Year of Registration:
4. Bidder’s Legal Address in Kenya
4. Bidder’s Authorized Representative Information
Name:
Address:
Telephone
Fax numbers:
2 Attached are copies of original documents of:
2.1 Articles of Incorporation or Registration of firm named in 1, above, in accordance
with ITB Sub-Clauses 4.1 and 4.2.
2.2 In case of JV, letter of intent to form JV or JV agreement, in accordance with ITB Sub-
Clause 4.1.
2.3 Copies of VAT and PIN Certificates
2.4 Copy of the Current Trade License
2.5 Tax compliance certificate
FORM OF TENDER
Tender for the -------------------------------------------------------------------------------------------------------------------
----------------------------------------------------------------------------------------------------------------------------- ---------
In accordance with the special specifications and the following drawings: -
-----------------------------------------------------------------------------------------------------------
To:
THE VICE CHANCELLOR
CHUKA UNIVERSITY,
P.O. BOX 109 - 60400
CHUKA.
I/we ----------------------------------------------------------------------------------------------------------------------------- --
--------------------------------------------------------------------------------------------------------------------------------------
(contractors name), under and subject to the conditions of tendering annexed hereto, hereby tender and offer to
execute and perform the works, provisions and supply all labour and materials and everything of every kind
respectively named, shown, described and / or included to ,in or to be in inferred from the general conditions of
contract, specifications and the drawings governing the contract between Chuka University and the main
contractor, and in conformity with the said specifications conditions and drawings for the lump sum named
herein below.
The undersigned agrees to be bound by and submit to the said general conditions of contract, specifications,
and priced Bills of Quantities which shall form a basis for the valuation of interim certificates and any extra or
omitted work which may from time to time be ordered by the Project Manager (P.M.)
The total sum of this tender in accordance with the specifications and/or Bills of Quantities is the lump sum of
Kenya shillings …………………………………………………………………………………………………
…………………………………………………………………………..………………………………………
Whereas it is understood that you reserve to yourself the right to agree or refuse this tender whether it is lower
or higher than any other tender or of the same amount, the undersigned agrees that the tender shall remain valid
and shall not be withdrawn within one hundred and fifty (150) days from the final date of submission of the
tenders stipulated in the advertisement or letter of invitation to tender.
And further the undersigned agrees, in the event of your acceptance of this tender, to enter into a contract as
herein before described within ten days of posting, or delivery if by hand, of Notification of Award.
Name and address of company…………………………….…………………………………………
........................................................................................................................................................
Name of person signing on behalf of company………………………………………………………..
Date ………………………….. Binding Signature …………….…………………….
Witness to signature of tender (Name) …………………………………………..
Signature ……………………………….
Address ……………………………… Date …………………………………. Page 2
CHUKA UNIVERSITY
DECEMBER, 2016 Page 3
other bid that you may receive.
Signature ……………………………………….
Name………………………………………………..
Designation………………………………………… Seal
Duly authorized to sign the bid for and on behalf
of:……………………………………………………. [Insert complete name of Bidder]
Dated on ____________ day of __________________, 20_______ [insert date of signing]
CHUKA UNIVERSITY
DECEMBER, 2016 Page 4
Appendix to Form of Tender
The following specific data for the contract shall complement, supplement, or amend the
provisions in the Instructions to Bidders (ITB). Whenever there is a conflict, the
provisions herein shall prevail over those in ITB.
Item Description Quantity/Limit Clause in FIDIC
Conditions of
Contract – Part 1
1. Amount of tender security as
bank guarantee
It is proportional to the
amount of pre-financing
requested
2. Amount of performance bond 10% of total tender price 10.1
3. Minimum amount of third
party insurance
Kshs.5,000,000 per
occurrence the number
unlimited
23.2
4. Time within which Engineer
shall issue notice to commence
the Works after the date of the
letter of acceptance.
28 days 43.1
5. Commencement date of works 30 days after receipt of
Engineer’s notice to
commence.
41.1
6. Time for completion * Calendar months 43.1
7. Amount of liquidated
damages for delay
KShs.100,000/= per day 47.1
8. Limit of liquidated damages 10% of the contract price 47.1
9. Defects liability period 12 months, after completion 49.1
10. Percentage of retention 10% of contract price 60.5
11. Mobilization advance, on
submission of bank guarantee
No advance payment shall
be made. Payments shall be
based on interim certificates
on works executed
60.7
12 Time within which payment
has to be made after delivery
of interim certificates to the
Employer
28 days 60.1
13 Appointer of arbitrator Chairman of the Engineer’s
Registration Board of Kenya
67.3
14 Rate of Interest upon unpaid
sums
2 percent points above the
Central bank of Kenya
lending rates to commercial
banks at the date of award
60.8
* To be inserted by the Tenderer
BID SECURITY
Whereas ……………………………………………………………………………………..
(Name of the tenderer)
Has submitted this tender dated ……………………………………………………. for the construction,
completion and maintenance of ………………………………………………………….
………………………………………………………………………………………………..
………………………………………………………………………………………………
KNOW ALL MEN by these present that we ………………………………………….
(Name of guarantor)
………………………………………….
(Registered address)
Are bound unto the government of Kenya (herein after called ''the employer") in the sum of Kenya shillings
(words) (As stated in the advertisement) for which payment shall well and truly be made to the said employer.
The guarantor binds itself, its successors and assignees to these presents sealed with the common seal of the
guarantor this …………………….. day of ……………..…….. 20….
THE CONDITIONS of this obligation are: -
(a) If the tenderer withdraws the tender during the period of tender validity specified in the form of
tender or: -
(b) If the tenderer, having being notified of the acceptance of its tender,
(i) Withdraws or
(ii) Fails or refuses to execute the Contract Agreement when required in accordance with
the conditions of tendering
(iii) Fails or refuses to furnish the performance bond guarantee required in accordance with
the conditions of tendering
Provided such notification shall have been made to the tenderer during the period of tender validity.
We undertake to pay the employer an amount not exceeding the above stated amount upon receipt of its first
written demand without having to substantiate its demand. Provide that in its demand the employer shall state
that the amount claimed by him is due to the occurrence of one or more of the stated CONDITIONS.
The validity of this guarantee shall be until one hundred and eighty days (180) days from date of tender
opening.
At the request of the employer the tender validity may be extended by mutual agreement between the employer
and the tenderer and we undertake to extend the validity of this guarantee accordingly, without you having to
inform us of such extension of tender validity period.
Page 5
CHUKA UNIVERSITY
DECEMBER, 2016 Page 6
Contract Agreement (sample form)
THIS CONTRACT AGREEMENT is made The……………day of…………………….20……..
BETWEEN
Chuka University incorporated under the laws of Kenya and having its principal place of
business at Chuka University (hereinafter called “the University”), and
…………………………………………………………………………………………………….name
of Contractor incorporated under the laws of Kenya and having its principal place of
business
at……………………………………………………………………………………………..address
of Contractor ] (hereinafter called “the Contractor”).
WHEREAS the University invited bids for the Construction of Chuka University
Wastewater Treatment Plant (EATP) and has accepted a Bid by the Contractor for the
construction Services in the sum of
Kshs……………………………………………………………………………………………………
……………….(in words)………………………………………(figures) (hereinafter called “the
Contract Price”).
NOW THIS AGREEMENT WITNESSETH AS FOLLOWS:
In this Agreement words and expressions shall have the same meanings as are respectively
assigned to them in the Conditions of Contract referred to.
The following documents shall constitute the Contract between the University and the
Contractor, and each shall be read and construed as an integral part of the Contract:
This Contract Agreement
Special Conditions of Contract
General Conditions of Contract
Technical Requirements (including Schedule of Requirements and Technical Specifications)
The Contractor’s Bid and original Price Schedules
The Corporation’s Notification of Award
This Contract shall prevail over all other Contract documents. In the event of any
discrepancy or inconsistency within the Contract documents, then the documents shall
prevail in the order listed above.
In consideration of the payments to be made by the University to the Contractor as
hereinafter mentioned, the Contractor hereby covenants with the University to provide the
Goods and Services and to remedy defects therein in conformity in all respects with the
provisions of the Contract.
CHUKA UNIVERSITY
DECEMBER, 2016 Page 7
The University hereby covenants to pay the Contractor in consideration of the
construction and the remedying of defects therein, the Contract Price or such other sum as
may become payable under the provisions of the Contract at the times and in the manner
prescribed by the Contract.
IN WITNESS whereof the parties hereto have caused this Agreement to be executed in
accordance with the laws of Kenya on the day, month and year indicated above.
For and on behalf of the Chuka University.
Signed:…………………………………………………………………..
Name: …………………………………..(in the capacity of Vice Chancellor)
in the presence of……………………………………………….
Designation……………………………………………………..
For and on behalf of the Contractor
Signed:…………………………………………………………………..
[signature of authorized representative(s) of the Contractor]
in the capacity of …………………………… [designation]
in the presence of……………………………. [identification of official witness]
………………………………………………….
CHUKA UNIVERSITY
DECEMBER, 2016 Page 8
Performance Security (Sample form)
[The bank, as requested by the successful Bidder, shall fill in this form in accordance with the
instructions indicated]
Tender No: ……………………………… Tender Name:. Construction of Chuka University
Extended Aeration Wastewater Treatment Plant (EATP)
Bank’s Branch or Office:…………………………………………………….complete name of
Guarantor
Beneficiary: Chuka University
PERFORMANCE GUARANTEE No.:…………………………
We have been informed that ……………………………………………….Contractor
(hereinafter called “the Contractor”) has entered into Contract No…....….. dated
…………….with you, for the Construction of Chuka University Extended Aeration
Wastewater Treatment Plant (EATP) (hereinafter called “the Contract”).
Furthermore, we understand that, according to the conditions of the Contract, a
Performance Guarantee is required.
At the request of the Contractor, we hereby irrevocably undertake to pay you any sum(s)
not exceeding ten percent of the total Contract Sum upon receipt by us of your first demand
in writing declaring the Contractor to be in default under the Contract, without cavil or
argument, or your needing to prove or to show grounds or reasons for your demand or the
sum specified therein.
This Guarantee shall expire not later than the …………day of…………… and any demand
for payment under it must be received by us at this office on or before that date.
…………………………………………………….
…………………………………………………….
[Signature(s) and seal of authorized representatives of the bank and the Contractor]
CHUKA UNIVERSITY
DECEMBER, 2016 Page 9
CONDITIONS OF CONTRACT
General Conditions of Contract
The conditions of contract comprise of two parts:
Part 1 – General Conditions of Contract
Part 2 – Conditions of Particular Application
The general conditions of contract are part 1 of the “Conditions of Contract for Works of
Civil Engineering Construction”, 4th Edition, 1987, reprinted 1992 with further
amendments, published by the Federation Internationale des Ingenieurs – Conseils (FIDIC),
and are not bound into this volume. The contractor shall be required to maintain his own
original text of the above publication in his office throughout the construction period.
The Conditions of Particular Application are included in herewith (also called the Special
Conditions of Contract) and shall have precedence over those of Part 1 (Sub Clause 5.2 of
Part 1).
CHUKA UNIVERSITY
DECEMBER, 2016 Page 10
Clause/Sub-Clause No. Description Page
1.1 Definitions ....................................................................................... 31
2.1 Engineer's Duties and Authority.................................................. 32
2.7 Duration of the Engineer's Powers............................................... 32
5.1 Language and Law........................................................................ 32
5.2 Priority of Contract Documents ................................................... 32
10.1 Performance Security...................................................................... 33
10.4 Claims against Contractor, General.............................................. 33
10.5 Cost of Securities............................................................................. 33
14.1 Programme to be Submitted ......................................................... 33
14.3 Cash Flow Estimate to be Submitted ........................................... 33
15.1 Contractor's Superintendence.........................................................33
15.2 Language Ability of Contractor's Representative........................33
16.3 Language Ability of Labour Supervisors......................................33
16.4 Employment of Local Personnel................................................... 33
16.5 Registration of Contractor's Employees ...................................... 34
19.1 Safety, Security and Protection of the Environment................... 34
20.4 Employer's Risks............................................................................. 35
21.1 Insurance of Works and Contractor's Equipment...................... 36
21.2 Scope of Cover................................................................................ 36
21.4 Exclusions......................................................................................... 36
25.1 Evidence and Terms of Insurances............................................... 36
34.2 Rates of Wages and Conditions of Labour.................................. 36
34.3 Employment of Persons in the Service of Others....................... 36
34.4 Repatriation of Labour.................................................................. 36
34.5 Housing for Labour........................................................................ 36
34.6 Health and Safety............................................................................ 37
34.7 Epidemics ....................................................................................... 37
34.8 Burial of the Dead ......................................................................... 37
34.9 Supply of Water............................................................................... 37
34.10 Arms and Ammunition....................................................................38
34.11 Festivals and Religious Customs ................................................. 38
34.12 Disorderly Conduct........................................................................ 38
34.13 Records of Labour........................................................................... 38
34.14 Trade Unions .................................................................................. 38
34.15 Observance by Subcontractors ..................................................... 38
35.2 Reporting of Accidents................................................................... 38
36.1 Quality of Materials, Plant and Workmanship............................ 39
36.6 Source of Plant and Materials ...................................................... 39
36.7 Procurement of Plant and Materials ..............................................40
41.1 Commencement of Works ............................................................ 40
42.1 Possession of Site and Access thereto.......................................... 40
42.4 Limitation of Access, Possession and Use of the Site.................. 40
44.3 Interim Determination of Extension............................................ 40
48.5 Prevention from Testing................................................................. 41
CHUKA UNIVERSITY
DECEMBER, 2016 Page 11
52.1 Valuation of Variations ................................................................. 41
52.3 Variations Exceeding 15 percent.................................................. 41
54.5 Conditions of Hire of Contractor's Equipment............... .............41
55.1 Quantities......................................................................................... 41
55.2 Omission of Rates and Prices........................................................ 42
58.2 Use of Provisional Sums ................................................................ 42
59.1 Definition of "Nominated Subcontractors"................................... 42
59.4 Payments to Nominated Subcontractors..................................... 42
60 Certificates and Payments ............................................................ 42
60.1 Monthly Statements ....................................................................... 43
60.2 Monthly Payments.......................................................................... 44
60.3 Materials and Plant for the Permanent Works............................ 45
60.4 Place of Payment............................................................................ 45
60.5 Retention Money............................................................................. 45
60.6 Payment of Retention Money........................................................ 46
60.7 Advance Payment........................................................................... 46
60.8 Time of Payment and Interest....................................................... 46
60.9 Correction of Certificates............................................................... 47
60.10 Statement at Completion........................................................... 47
60.11 Final Statement....................................................................... … 47
60.12 Discharge........................................................................................... 48
60.13 Final Certificate................................................................................ 48
60.14 Cessation of Employer's Liability.................................................. 48
63.1 Default of Contractor...................................................................... 48
63.2 Valuation at Date of Expulsion .................................................... 48
63.3 Payment after Expulsion .............................................................. 49
63.4 Assignment of Benefit of Agreement.......................................... 49
63.5 Corrupt or Fraudulent Practices .................................................. 49
65.2 Special Risks .................................................................................... 49
67.3 Arbitration........................................................................................ 49
68.1 Notice to Contractor....................................................................... 50
68.2 Notice to Employer and Engineer................................................. 50
69 Default of Employer....................................................................... 50
69.1 Default of Employer...................................................................... 50
70 Changes in Cost and Legislation................................................... 50
70.1 Price Increases ................................................................................ 50
70.2 Subsequent Legislation................................................................... 51
73 Taxation ........................................................................................... 51
73.1 Foreign Taxation............................................................................. 51
73.3 Income Taxes on Staff..................................................................... 51
74.1 Bribes................................................................................................ 51
74.2 Individuals not Personally Liable ................................................ 51
75.1 Termination of Contract for Employer's Convenience............... 52
77.1 Joint and Several Liabilities........................................................... 52
78.1 Details to be Confidential............................................................... 52
78.2 Declaration against Waiver............................................................ 52
CHUKA UNIVERSITY
DECEMBER, 2016 Page 12
79.1 Repayment....................................................................................... 52
CHUKA UNIVERSITY
DECEMBER, 2016 Page 13
Special Conditions of Contract
The following Special Conditions of Contract (SCC) also called Conditions of Particular
Application shall supplement and / or amend the General Conditions of Contract (GCC).
Whenever there is a conflict, the provisions herein shall prevail over those in the GCC.
Sub clause 1.1
Definitions
(a) (i) The Employer is:
Chuka University
P. O. Box 109 - 60400
Chuka.
(iv) The Architect is:
Conte Design Architects,
Landscape Architects and
Environmental Planners
P.O BOX 66669-00800
(v) The Civil & Structural Engineer
Multiscope Consulting Engineers
Silverpool Office Suites,Jabavu Lane, Hurlingham
P.O. BOX 12012 - 00100, Nairobi, Kenya.
Subpara. (b) (v) of Sub-Clause 1.1 is amended by the addition of the
following words at the end:
The word "Tender" is synonymous with "Bid" and the
words "Tender Documents" with "Bid Documents".
Subpara. (b) (vi) is amended by the addition of the following words:-
"Letter of Acceptance" means "Letter of Award".
Subpara. (d) (ii) is amended by the addition of the following words:-
"Taking-Over Certificate" means "Completion Certificate".
Subpara. (e) (i) is amended by the addition of the following words:-
"Contract Price" means "Contract Sum".
The Engineer shall obtain the specific approval of the Employer before
taking any of the following actions specified in Part I:
CHUKA UNIVERSITY
DECEMBER, 2016 Page 14
Sub-Clause 2.1
Engineer's Duties
and Authority
(a) approving subletting of any part of the Works under Clause 4;
(b) certifying additional cost determined under Clause 12;
(c) determining an extension of time under Clause 44;
(d) issuing a variation under Clause 51, except:
(i) in an emergency situation as reasonably determined
by the Engineer; or
(ii) if such variation would not increase the Contract Price; or,
(e) fixing rates or prices under Clause 52.
Notwithstanding the obligation, as set out above, to obtain approval, if,
in the opinion of the Engineer, an emergency occurs affecting the
safety of life or of the Works or of adjoining property, he may, without
relieving the Contractor of any of his duties and responsibilities under
the Contract, instruct the Contractor to execute all such work or to do
all such things as may, in the opinion of the Engineer, be necessary to
abate or reduce the risk. The Contractor shall forthwith comply,
despite the absence of approval of the Employer, with any such
instruction of the Engineer. The Engineer shall determine an addition
of the Contract Price, in respect of such instruction, in accordance with
Clause 52 and shall notify the Contractor accordingly, with a copy to
the Employer.
Sub-Clause 2.7
Duration of the
Engineer's Powers
Add a new Sub-Clause 2.7 as follows:-
The powers of the Engineer shall continue and be in force and
exercisable until all claims by the Contractor against the Employer and
all claims by the Employer against the Contractor have been
determined.
Sub-Clause 5.1
Language and Law
(a) The language is English.
(b) The law is that in force in the Republic of Kenya.
Sub-Clause 5.2
Priority of Contract
Documents
Delete the documents listed 1 - 6 and substitute:
(1) the Contract Agreement (if completed);
(2) the Letter of Acceptance;
(3) the Form of Tender and the Appendix to Tender;
(4) the Conditions of Contract Part II;
(5) the Conditions of Contract Part I;
(6) the Specifications and Schedules;
(7) the Drawings; and
(8) the priced Bill of Quantities.
CHUKA UNIVERSITY
DECEMBER, 2016 Page 15
Sub-Clause 10.1
Performance
Security
Replace the text of Sub-Clause 10.1 with the following:
The Contractor shall provide security for his proper performance of
the Contract to the Employer within 30 days after the receipt of the
Letter of Acceptance. The performance security shall be in the form of
a bank guarantee. The amount of the bank guarantee or the standby
letter of credit shall be as stipulated in the Appendix to Tender.
It shall be issued either by a bank located in the country of the
Employer. The performance security shall be denominated in Kshs.
Without limitation to the provisions of the preceding paragraph,
whenever the Engineer determines an addition to the Contract Price as
a result of a change in cost and/or legislation or as a result of a
variation amounting to more than 25 percent of the portion of the
Contract Price payable in a specific currency, the Contractor, at the
Engineer's written request shall promptly increase the value of the
performance security in that currency by an equal percentage.
Sub-Clause 10.5
Cost of Securities
Add a new Sub-Clause 10.5 as follows:
The cost of complying with the requirements of this Clause shall be
borne by the Contractor.
Sub-Clause 14.1
Programme to be
Submitted
The time within which the programme shall be submitted shall be 14
days.
Sub-Clause 14.3
Cash Flow Estimate
to be Submitted
The time within which the detailed cash flow estimate shall be
submitted shall be 14 days.
Sub-Clause 15.1
Contractor's
Superintendence
Add the following sentence at the end of Sub-Clause 15.1:
The Contractor shall not withdraw any of his senior staff from the Site
without the express approval of the Engineer.
Sub-Clause 15.2
Language Ability
of
Contractor's
Representative
Add the following Sub-Clause 15.2:
The Contractor's authorised representative on site shall be able to read,
write and speak English fluently
Sub-Clause 16.3
Language Ability
of Labour
Supervisors
Add the following Sub-Clause 16.3:
A reasonable proportion of the Contractor's labour supervisors shall
have a working knowledge of English or the Contractor shall have
available on site at all times a sufficient number of competent
interpreters to ensure the proper transmission of instructions and
information.
CHUKA UNIVERSITY
DECEMBER, 2016 Page 16
Sub-Clause 16.4
Employment of
Local Personnel
Add the following Sub-Clause 16.4:
The Contractor is encouraged, to the extent practicable and reasonable,
to employ staff and labour from sources within Kenya.
Sub-Clause 16.5
Registration of
Contractor's
Employees
Add the following Sub-Clause 16.5:
The Contractor shall be responsible for making all arrangements and
registrations and shall bear all costs relative to obtaining all necessary
documents, visas, residence or other permits, identity cards etc, for his
personnel for the execution of the Works within the regulations
prevailing and applied in the Republic of Kenya.
Sub-Clause 19.1
Safety, Security and
Protection of the
Environment
Add sub-para, (d) to (g) of Sub-Clause 19.1 as follows:
(d) Notwithstanding General Conditions of Contract Clause 19.1(c), the
Contractor shall execute the Works in accordance with the
Environmental Management Plan (EMP) prepared for the particular
Works. Where an EMP does not exist, the clauses contained herein
shall form the basis of a management plan.
(e) Notwithstanding the Contractor's obligation under the above
Clause 19.1 (d), the Contractor shall:
(i) Implement all measures necessary to conserve and reduce
negative impacts on the existing environment.
(ii) Carry out all necessary works to restore the Site as far as
practicable to its original condition, all to the approval of the Engineer.
(iii) Abide by environmental performance indicators as specified in the
National Standard Regulations/ Guidelines and clarified as necessary
by the Engineer; and measure progress towards achieving
environmental objectives during execution and upon completion of the
Works.
(iv) Adhere to the activity implementation schedule agreed upon with
the Engineer to facilitate monitoring activities and adapt impact
management to changing and unforeseen conditions.
(f) Allow full access to the Site and co-operate with representatives of
the Employer, for monitoring implementation of the environmental
impact mitigation measures, who will report their findings to the
Engineer for any action.
If the Contractor fails to implement the approved Environmental Management Plan or contravenes any order as instructed by the Engineer, the Employer shall be entitled to seek legal redress through NEMA or under any appropriate Kenyan legislation.
CHUKA UNIVERSITY
DECEMBER, 2016 Page 17
Sub-Clause 20.4
Employer's Risks
Sub-Clause 20.4 is amended to read as follows: The Employer's risks
are:
(a) insofar as they directly affect the execution of the Works in Kenya:
(i) war and hostilities (whether war be declared or not), invasion, act
of foreign enemies;
(ii) rebellion, revolution, insurrection, or military or usurped power,
or civil war;
(iii) ionizing radiations, or. contamination by radioactivity from any
nuclear fuel, or from any nuclear waste from the combustion of nuclear
fuel, radioactive toxic explosive or other hazardous properties of any
explosive nuclear assembly or nuclear component thereof;
(iv) pressure waves caused by aircraft or other aerial devices travelling
at sonic or supersonic speeds;
(v) riot, commotion or disorder, unless solely restricted to the
employees of the Contractor or of his Subcontractors and arising from
the conduct of the Works;
(b) loss or damage due to the use or occupation by the Employer of
any Section or part of the Permanent Works, except as may be
provided for in the Contract;
(c) loss or damage to the extent that it is due to the design of the
Works, other than any part of the design provided by the Contractor or
for which the Contractor is responsible;
(d) any operation of the forces of nature (insofar as it occurs on the
Site) which an experienced contractor:
(i) could not have reasonably foreseen, or
(ii) could reasonably have foreseen, but against which he could not
reasonably have taken at least one of the following measures:
(A) prevent loss or damage to physical property from occurring by
taking appropriate measures, or
(B) insure against such loss or damage.
CHUKA UNIVERSITY
DECEMBER, 2016 Page 18
Sub-Clause 21.1
Insurance of Works
and Contractor's
Equipment
Add the following words at the end of sub-paras, (a) and (b) of Sub-
Clause 21.1:
", it being understood that such insurance shall provide for
compensation to be payable in Kshs. required to rectify the loss or
damage incurred."
Sub-Clause 21.2
Scope of Cover
Para, (a) of Sub-Clause 21.2 is amended by deletion of the words "from
the start of work at the Site" and by the substitution
Sub-Clause 21.3
therefore of the words:
"from the first day after the Commencement Date".
Sub-Clause 21.4
Exclusions
Sub-Clause 21.4 is amended to read as follows:
There shall be no obligation for the insurances in Sub-Clause 21.1 to
include loss or damage caused by the risks listed under Sub-Clause
20.4 paragraphs (a) (i) to (iv).
Sub-Clause 25.1
Evidence and
Terms of
insurances
Sub-Clause 25.1 is amended by inserting the words
"as soon as practicable after the respective insurances have been taken
out but in any case" before the words "prior to the start of work at the
Site"
Sub-Clause 34.2
Rates of Wages and
Conditions of
Labour
Add the following Sub-Clause 34.2:-
The Contractor shall as a minimum comply with the Labour
Regulations of Kenya and shall pay rates of wages and observe
conditions of labour not less favorable than those established for the
trade or industry where the work is carried out. In the absence of any
rates of wages or conditions of labour so established, the Contractor
shall pay rates of wages and observe conditions of labour which are
not less favorable than the general level of wages and conditions
observed by other employers whose general circumstances in the trade
or industry in which the Contractor is engaged are similar.
Sub-Clause 34.3
Employment of
Persons in the
Service of Others
Add the following Sub-Clause 34.3:-
The Contractor shall not recruit or attempt to recruit his staff and
labour from amongst persons in the service of the Employer or the
Engineer.
Sub-Clause 34.4
Repatriation of
Labour
Add the following Sub-Clause 34.4:-
The Contractor shall be responsible for the return to the place where
they were recruited or to their domicile of all such persons as he
recruited and employed for the purposes of or in connection with the
Contract and shall maintain such persons as are to be so returned in a
suitable manner until they shall have left the Site or, in the case of
persons who are not nationals of and have been recruited outside
Kenya shall have left Kenya.
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Sub-Clause 34.5
Housing for
Labour
Add the following Sub-Clause 34.5:-
Save insofar as the Contract otherwise provides, the Contractor shall
provide and maintain such accommodation and amenities as are
necessary for all his staff and labour, employed for the purposes of or
in connection with the Contract, including all fencing, water supply
(both for drinking and other purposes), electricity supply, sanitation,
cookhouses, fire prevention and fire-fighting equipment, cookers,
refrigerators, furniture and other requirements in connection with
such accommodation or amenities.
On completion of the Contract unless otherwise agreed with the
Employer the temporary camps/housing provided by the Contractor
shall be removed and the site reinstated to its original condition all to
the approval of the Engineer.
Sub-Clause 34.6
Health and Safety
Add the following Sub-Clause 34.6. Due precautions shall be taken by
the Contractor, and at his own cost, to ensure the safety of his staff and
labour and, in collaboration with and to the requirements of the local
health authorities, to ensure that first aid equipment and stores are
available at the camps, housing and at all places on the Site at which
work is being executed at all times throughout the period of the
Contract and that suitable arrangements are made for the prevention
of epidemics and for all necessary welfare and hygiene requirements.
The Contractor shall at all times take the necessary precautions to
protect all staff and labour employed on the Site from insect nuisance,
rats, and other pests and reduce the dangers to health and the general
nuisance caused by the same. The Contractor shall provide his staff
and labour with suitable prophylactics for the prevention of malaria,
and take steps to prevent the formation of stagnant pools of water. He
shall comply with all the regulations of the local health authorities in
these respects and shall in particular arrange to spray thoroughly with
approved insecticide all buildings erected on the Site. Such treatment
shall be carried out at least once every three months or as instructed by
the Engineer.
Sub-Clause 34.7
Epidemics
Add the following Sub-Clause 34.7:-
In the event of any outbreak of illness of an epidemic nature, the
Contractor shall comply with and carry out such regulations, orders
and requirements as may be made by the Government or the local
medical or sanitary authorities, for the purpose of dealing with and
overcoming the same.
Sub-Clause 34.8
Burial of the Dead
Add the following Sub-Clause 34.8:-
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The Contractor shall make any necessary arrangements for the
transport, to any place as required for burial, of any of his expatriate
employees or members of their families who may die in Kenya. The
Contractor shall also make any necessary arrangements for the
transport to any place in Kenya as required for burial, of any of his
local employees who may die while engaged upon the Works.
Sub-Clause 34.9
Supply of Water
Add the following Sub-Clause 34.9
The Contractor shall provide on the site an adequate supply of
drinking and other water for the use of his staff and labour.
Sub-Clause 34.10
Arms and
Ammunition
Add the following Sub-Clause 34.10:-
The Contractor shall not give, or otherwise dispose of to any person or
persons, any arms or ammunition of any kind or permit or suffer the
same as aforesaid.
Sub-Clause 34.11
Festivals and
Religious Customs
Add the following Sub-Clause 34.11 :-
The Contractor shall in all dealings with his staff and labour have due
regard to all recognized festivals, days of rest and religious and other
customs.
Sub-Clause 34.12
Disorderly
Conduct
Add the following Sub-Clause 34.12:-
The Contractor shall at all times take all reasonable precautions to
prevent any unlawful, riotous or disorderly conduct by or amongst his
staff and labour and for the preservation of peace and protection of
persons and property in the neighbourhood of the Works against the
same.
Sub-Clause 34.13
Records of Labour
Add the following Sub-Clause 34.13:-
The Contractor shall keep proper wages books, in English, showing the
time worked and wages paid to all tradesmen, artisans and labour
engaged on the Works, together with such other records as are
required by any Statute, Ordinance, Law, Regulation or Bye-Law in
force in the Republic of Kenya governing the employment of labour.
He shall be bound, whenever required, to produce such wages books
and other records for the inspection of any persons authorised by the
Engineer.
Should a claim be made to the Employer alleging the Contractor's
default in payment of wages, in accordance with the requirements of
this Clause, to any employees on the Works, and if proof thereof
satisfactory to the Employer is furnished, the Employer may, failing
payment by the Contractor, pay the claims out of any monies due or
CHUKA UNIVERSITY
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which may become due to the Contractor under the Contract.
Sub-Clause 34.14
Trade Unions
Add the following Sub-Clause 34.14:-
The Contractor shall recognize the freedom of his employees to be
members of trade unions.
Sub-Clause 34.15
Observance by
Subcontractors
Add the following Sub-Clause 34.15:-
The Contractor shall ensure that all Subcontractors engaged upon the
Works, observe all the requirements of Clause 34.
Sub-Clause 35.2
Reporting of
Accidents
Add the following Sub-Clause 35.2:
The Contractor shall report to the Engineer details of any accident
involving damage to property or injury to persons occurring on the
site soonest possible after its occurrence. In the case of any fatality or
serious accident, the Contractor shall, in addition, notify the Employer
immediately by the quickest available means.
Sub-Clause 36.1
Quality of
Materials, Plant
and Workmanship
Add the following paragraph at the end of Sub-Clause 36.1:-
All Plant and materials shall be new, except as may be provided
elsewhere in the Specifications and Drawings, and manufactured,
handled, transported and installed in a workmanlike manner.
Manufacturers' warranties, guarantees, instruction sheets and parts
lists, which are furnished with Plant and material to be incorporated in
the Works, shall be delivered to the Engineer before acceptance of
those articles.
Sub-Clause 36.6
Source of Plant and
Materials
Add the following Sub-Clause 36.6:-
The Contractor shall provide the Engineer with a list of his sources of
Plant and materials. The list shall be submitted in a prescribed form
and be delivered to the Engineer in sufficient time to permit proper
inspection and testing of Plant and materials, to be procured from such
listed sources, in advance of their use.
The Contractor is encouraged, to the extent practicable and reasonable,
to use Plant and materials from sources, within Kenya.
Sub-Clause 36.7
Procurement of
Plant and Materials
Add the following Sub-Clause 36.7:-
The Contractor shall provide the Engineer with copies of all orders and
procurement schedules for the supply of Plant and materials to be
incorporated in the Works which the Engineer may require. Plant and
materials to be incorporated in the Works shall be stored in such a
manner as to ensure the preservation of their quality and suitability for
the Works, and to facilitate inspection.
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Sub-Clause 41.1
Add the following paragraphs at the end of Sub-Clause 41.1:
(1) Upon acceptance of the tender the contractor shall proceed with
due dispatch to prepare full details and particulars of major materials
which he intends to procure for the execution of the works and shall
submit these details and particulars to the engineer for approval
within 7 days of acceptance of the tender. Upon such approval, the
contractor shall within 7 days thereafter place orders with his
suppliers for the major materials or commence such other procedures
or formalities as may be required by the relevant authorities towards
such procurement.
(2) The contractor shall take all measures as shall be practicable or shall
be required by the engineer towards the earliest possible procurement
of the major materials. All orders, applications, notices,
correspondence and the like from the contractor in respect of the major
materials shall be copied to the Engineer and the Engineer's
Representative and the Contractor shall provide copies to the Engineer
and the Engineer's Representative of any correspondence, licenses,
permits, shipping documents and the like received by him which are
in any manner whatsoever related to the procurement of the major
materials within 7 days of his receipt of such correspondence and the
like.
(3) The Contractor shall commence the Works on Site within 14 days
after the receipt by him of an order in writing to this effect from the
Engineer and shall proceed with the same with due expedition and
without delay except as may be expressly sanctioned or ordered by the
Engineer or be wholly beyond the Contractor's Control.
(4) Save that notwithstanding the provisions of this clause, the
Contractor shall erect, maintain, watch and care over secure buildings
and facilities for storage of the major materials on Site subsequent to
their delivery to Site. The facilities and arrangements for such storage
and their location shall be subject to the approval of the Engineer. The
erection of such storage shall not be construed as commencement, of
works on Site.
42.1
Possession of Site
and Access thereto
Add the following paragraph at the end of Sub-Clause 42.1:
The Employer will give possession of the Site to the Contractor as
aforesaid, free of charge, and provide compensation to the owners
thereof for any crops or property standing at the date of possession.
Sub-Clause 42.4
Limitation of
Access, Possession
Add the following Sub-Clause 42.4:
Possession of the Site shall be deemed to give the Contractor only such
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and Use of the Site
limited possession of it as shall be necessary to enable him, effectively,
to perform the work required under the Contract and shall not be
deemed to confer upon the Contractor a right to exclusive possession.
Sub-Clause 44.3
Interim
Determination of
Extension
Delete Sub-Clause 44.3.
Sub-Clause 48.5
Prevention from
Testing
Add the following Sub-Clause 48.5:
If the Contractor is prevented from carrying out the Tests on
Completion solely by a cause for which the Employer or the Engineer
or other contractors employed by the Employer are responsible, the
Employer shall be deemed to have taken over the Works on the date
when the Tests on Completion would have been completed but for
such prevention. The Engineer shall issue a Taking-Over Certificate
accordingly. Provided always that the Works shall not be deemed to
have been taken over if they are not substantially in accordance with
the Contract.
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Sub-Clause 54.5
Conditions of Hire
of
Contractor's
Equipment
Add a final paragraph to Sub-Clause 54.5 as follows:
Within 14 days of any Contractor's Equipment being brought onto the
site, the Contractor shall notify the Engineer of the ownership of the
Equipment. For Equipment owned by the Contractor, copies of
documents of ownership shall be provided with the notification, and
for other Equipment copies of the agreement for hire thereof shall be
provided.
Sub-Clause 55.1
Quantities
Add a final paragraph to Sub-Clause 55.1 as follows:
Where any particular aspect of work or obligation of the Contract is not
specifically itemized, the costs in respect thereof shall be deemed to be
included within the available Bill of Quantities items.
Sub-Clause 55.2
Omission of Rates
and Prices
Add Sub-Clause 55.2 as follows:
Items of the Works described in the Bill of Quantities for which no rate
or price has been entered shall be considered as included in other rates
and prices in the Contract and will not be paid for separately by the
Employer.
If the Works are taken over under this Sub-Clause the Contractor shall
nevertheless carry out the Tests on Completion during the Defects
Liability Period. The Engineer shall require the Tests to be carried out
by giving 14 days notice. Any additional costs which the Contractor
may incur, in making the Tests on Completion during the Defects
Liability Period, shall be added to the Contract Price.
Sub-clause
49.4
Extension of
Defects
Liability period
For electrical
And Mechanical
Equipment
Add the following sub-clause 49.4
The defects liability period for electrical and mechanical equipment
supplied shall be extended by a period equal to the period during
which the equipment cannot be used by reason of a defect or damage.
In such a case the total length of the Defects Liability Period for
electrical and mechanical equipment shall not exceed 2 years.
Sub-clause 52.2
Engineer to Fix
Rates
Supplement sub-clause 52.2 with the following:
Provided further that no change in the rate or price for any item
contained in the Contract shall be considered unless such item
accounts for an amount of more than two (2) per cent of the Contract
Price, and the actual quantity of work executed under the item exceeds
or falls short of the quantity set out in the Bill of Quantities by more
than twenty five (25) per cent.
No change of rate for the supply items shall be adjusted whatsoever.
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Sub-Clause 58.2
Use of
Provisional
Sums
Delete Sub-Clause 58.2 and substitute:
In respect of every Provisional Sum the Engineer shall have authority
to issue instructions for the execution of work or for the supply of
goods, materials, Plant or services by the Contractor, or by a
nominated Subcontractor as hereinafter defined. Payment to the
Contractor under such Provisional Sums shall be determined as
follows:
Sub-Clause 59.1
Definition of
"Nominated
Subcontractors"
(a) For work executed by the Contractor, the Contractor shall be
entitled to be paid an amount equal to the value thereof determined in
accordance with Clause 52.
(b) For the supply of goods, materials, Plant or services by the
Contractor, the Contractor shall be entitled to be paid the actual price
of the goods, materials, Plant or services (Prime Cost), together with a
percentage adjustment on the Prime Cost. Except as may be otherwise
allowed, the adjustment shall be at the rate stated in the Appendix to
Tender, and shall be deemed to be the cost to the Contractor of
effecting and administering the Contract, and the Contractor's
overhead cost and profit in respect thereof.
(c) In the case of execution of work or supply of goods, materials,
Plant or services by a nominated Subcontractor, the Contractor shall be
entitled to an amount determined and paid in accordance with Sub-
Clause 59.4.
Sub-Clause 59.4
Payments to
Nominated
Subcontractors
Add a final sentence to Sub-Clause 59.1 as follows:
The nomination, selection or approval of a nominated Subcontractor by
the Employer or the Engineer shall not relieve the Contractor from any
liability or obligation under the Contract and he shall be responsible
for the acts, defaults and neglects of any nominated Subcontractor, his
agents, servants or workmen as fully as if they were the acts, defaults
or neglects of the Contractor, his agents, servants or workmen.
Clause 60
Certificates and
Payments
Delete the first line of paragraph (c) in Sub-Clause 59.4 and substitute:
"(c) in respect of the cost to the Contractor of assuming all of the risk
for the performance of the nominated Subcontractor, and in respect of
all other charges and profit, a sum being a percentage rate of the..."
Sub-Clause 60.2
Monthly Payments
The said statement shall be approved or amended by the Engineer
in such a way that, in his opinion,, it reflects the amounts in various
currencies due in accordance with the Contract, after deduction, other
than pursuant to Clause 47, of any sums which may have become due
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and payable by the Contractor to the Employer. In cases where there is
a difference of opinion as to the value of any item, the Engineer's view
shall prevail. In the event of amendments required, the
Contractor shall do these changes as instructed and return the
statements in the required number of copies to the Engineer. Within 28
days of receipt of the approved monthly statement referred to in Sub-
Clause 60.1, the Engineer shall issue to the Employer and the
Contractor a certificate herein called "Interim Payment Certificate",
certifying the amounts due to the Contractor. Provided that the
Engineer shall not be bound to certify any payment under this Sub-
Clause if the net amount thereof, after all retentions and deductions,
would be less than the Minimum Amount of Interim Payment
Certificates stated in the Appendix to Tender.
Notwithstanding the terms of this Clause or any other Clause of the
Contract, no amount will be certified by the Engineer for payment until
the performance security has been provided by the Contractor and
approved by the Employer.
Sub-Clause 60.3
Materials and Plant
for the Permanent
Works
With respect to materials and Plant brought by the Contractor to the
Site for incorporation in the Permanent Works, the Contractor shall (i)
receive a credit in the month in which these materials and Plant are
brought to the Site and (ii) be charged a debit in the month in which
they are incorporated in the Permanent Works, both such credit and
debit to be determined by the Engineer in accordance with the
following provisions:
(a) no credit shall be given unless the following conditions shall have
been met to the Engineer's satisfaction:
(i) the materials and Plant in the list are in accordance with the
specifications for the Works;
(ii) the materials and Plant have been delivered to the Site and are
properly stored and protected against loss, damage or
deterioration;
(iii)the Contractor's records of the requirements, orders, receipts and
use of materials and Plant are kept in a form approved by the
Engineer, and such records are available for inspection by the
Engineer;
(iv)The Contractor has submitted a statement of his cost of acquiring
the materials and Plant, together with such documents as may be
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required for the purpose of evidencing such cost; and
(v) the origin of the materials and Plant and the currencies of payment
therefore are those indicated in the Appendix to Tender.
(b) the amount to be credited to the Contractor shall be 75 percent of
the Contractor's reasonable cost of acquiring the materials and
Plant delivered to the Site, as determined by the! Engineer after
review of the documents listed in paragraph (a) (iv) above;
(c) the amount to be debited to the Contractor for any
materials and Plant incorporated into the Permanent Works
Sub-Clause 60.4
Place of Payment
shall be equivalent to the credit previously granted to the Contractor
for such materials and Plant pursuant to Sub-Clause (b) above, as
determined by the Engineer; and
Sub-Clause 60.5
Retention Money
Payments to the Contractor by the Employer shall be made in the
currencies in which the Contract Price is payable, into a bank account
or accounts nominated by the Contractor.
Sub-Clause 60.6
Payment of
Retention Money
A retention amounting to 10 percent of the amounts due and
determined in accordance with the procedure set out in Sub-Clause
60.1 (i) shall be made by the Engineer in the first and following Interim
Payment Certificates.
Upon the issue of the Taking-Over Certificate with respect to the
whole of the Works, one half of the Retention Money, or upon the
issue of a Taking-Over Certificate with respect to a Section or part of
the Permanent Works only such proportion thereof as the Engineer
determines having regard to the relative value of such Section or part
of the Permanent Works, shall be certified by the Engineer for
payment to the Contractor.
Upon the expiration of the Defects Liability Period for the Works the
other half of the Retention Money shall be certified by the Engineer for
payment to the Contractor.
Provided that, in the event of different Defects Liability Periods being
applicable to different Sections or parts of the Permanent Works
pursuant to Clause 48, the expression "expiration of the Defects
Liability Period" shall, for the purposes of this Sub-Clause, be deemed
to mean the expiration of the latest of such periods.
Provided also that if at such time, there shall remain to be executed by
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the Contractor any work ordered, pursuant to Clauses 49 and 50, in
respect of the Works, the Engineer shall be entitled to withhold
certification until completion of such work of so much of the balance of
the Retention Money as shall, in
the opinion of the Engineer, represent the cost of the work remaining
to be executed.
Sub-Clause 60.8
Time of Payment
and Interest
The amount due to the Contractor under any Interim Payment
Certificate issued by the Engineer pursuant to this Clause, or to any
other term of the Contract, shall, subject to Clause 47, be paid by the
Employer to the Contractor within 28 days after the Contractor's
monthly statement has been received by the Employer or, in the case of
the Final Certificate pursuant to Sub-Clause 60.13, within 84 days after
the agreed Final Statement and written discharge have been submitted
to the Engineer for certification.
In the event of failure of the Employer to make payment within the
times stated, the Employer shall pay to the Contractor simple interest
at the rate stated in the Appendix to Tender upon all sums unpaid
from the date upon which the same should have been paid, in the
currencies in which the payments are due.
Sub-Clause 60.9
Correction of
Certificates
The Engineer may by any Interim Payment Certificate make any
correction or modification in any previous Interim Payment Certificate
which has been issued by him, and shall have authority, if any work is
not being carried out to his satisfaction, to omit or reduce the value of
such work in any Interim Payment Certificate.
Sub-Clause 60.10
Statement at
Completion
Not later than 21 days after the issue of the Taking-Over Certificate in
respect of the whole of the Works, the Contractor shall submit to the
Engineer a Statement at Completion with supporting documents
showing in detail, in the form approved by the Engineer,
(a) the final value of all work done in accordance with the Contract up
to the date stated in such Taking-Over Certificate;
(b) any further sums which the Contractor considers to be due; and
(c) an estimate of amounts which the Contractor considers will become
due to him under the Contract.
Estimated amounts shall be shown separately in such Statement at
Completion. The Engineer shall certify payment in accordance with
Sub-Clause 60.2.
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Sub-Clause 60.11
Final Statement
Not later than 21 days after the issue of the Defects Liability Certificate
pursuant to Sub-Clause 62.1, the Contractor shall submit to the
Engineer for consideration a draft final statement with supporting
documents showing in detail, in the form approved by the Engineer,
(a) the value of all work done in accordance with the Contract; and
(b) any further sums which the Contractor considers to be due to him
under the Contract.
If the Engineer disagrees with or cannot verify any part of the draft
final statement, the Contractor shall submit such further information as
the Engineer may reasonably require and shall make such changes in
the draft as may be agreed between them. The Contractor shall then
prepare and submit to the Engineer the final statement as agreed (for
the purposes of these Conditions referred to as the "Final Statement").
If, following discussions between the Engineer and the Contractor and
any changes to the draft final statement which may be agreed between
them, it becomes evident that a dispute exists, the Engineer shall issue
to the Employer an Interim Payment Certificate for those parts of the
draft final statement which are not in dispute. The dispute shall then
be settled in accordance with Clause 67. The Final Statement shall be
agreed upon settlement of the dispute.
Sub-Clause 60.12
Discharge
Upon submission of the Final Statement, the Contractor shall give to
the Employer, with a copy to the Engineer, a written discharge
confirming that the total of the Final Statement represents full and final
settlement of all monies due to the Contractor arising out of or in
respect of the Contract. Provided that such discharge shall become
effective only after payment due under the Final Certificate issued
pursuant to Sub-Clause 60.13 has been made and the performance
security referred to in Sub-Clause 10.1 has been returned to the
Contractor.
Sub-Clause 60.13
Final Certificate
Within 28 days after receipt of the Final Statement, and the written
discharge, the Engineer shall issue to the Employer (with a copy to the
Contractor) a Final Certificate stating
(a) the amount which, in the opinion of the Engineer, is finally due
under the Contract, and
(b) after giving credit to the Employer for all amounts previously
paid by the Employer and for all sums to which the Employer is
entitled under the Contract, other than Clause 47, the balance, if any,
due from the Employer to the Contractor or from the Contractor to the
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Employer as the case may be.
Sub-Clause 60.14
Cessation of
Employer's
Liability
The Employer shall not be liable to the Contractor for any matter or
thing arising out of or in connection with the Contract or execution of
the Works, unless the Contractor shall have included a claim in respect
thereof in his Final Statement and (except in respect of matters or
things arising after the issue of the Taking-Over Certificate in respect
of the whole of the Works) in the Statement at Completion referred to
in Sub-Clause 60.10.
Sub-Clause 63.1
Default of
Contractor
Delete the last paragraph of this Sub-Clause and substitute the
following:
"... then the Employer may, after giving fourteen days' notice in
writing to the Contractor, enter upon the Site and expel the Contractor
there from without thereby voiding the Contract, or releasing the
Contractor from any of his obligations or liabilities under the Contract,
or affecting the rights and powers conferred on the Employer or the
Engineer by the Contract, and may himself complete the Works or may
employ any other contractor to complete the Works.
The Employer or such other contractor may use for such completion so
much of the Contractor's Equipment, Plant, Temporary Works and
materials, which have been deemed to be reserved exclusively for the
execution of the Works, under the provisions of the Contract, as he or
they may think proper, and the Employer may, at any time, sell any of
the said Contractor's Equipment, Temporary Works and unused Plant
and materials and apply the proceeds of sale in or towards the
satisfaction of any sums due or which may become due to him from
the Contractor under the Contract."
Sub-Clause 63.2
Valuation at Date
of Expulsion
Modify the heading of Sub-Clause "63.2 by substituting "Valuation at
Date of Expulsion" for "Valuation at Date of Termination". In Sub-
Clause 63.2, delete the word "termination" on the second and fifth lines
and substitute: "expulsion".
Sub-Clause 63.3
Payment after
Expulsion
Modify the heading of Sub-Clause 63.3 by substituting "Payment after
Expulsion" for "Payment after Termination". In Sub-Clause 63.3, delete
the words "terminates the Contractor's employment" on the first line
and substitute "shall enter and expel the Contractor".
Sub-Clause 63.4
Assignment of
Benefit of
Agreement
In Sub-Clause 63.4, delete the word "termination" on the second line
and substitute:" expulsion".
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Sub-Clause 63.5
Corrupt or
Fraudulent
Practices
Add Sub-Clause 63.5:
If in the judgement of the Employer the Contractor has engaged in
corrupt or fraudulent practices, in competing for or in executing the
Contract, then the Employer may, after having given 14 days notice to
the Contractor, terminate the Contractor's employment under the
Contract and expel him from the Site, and the provisions of Clause 63
shall apply as if such expulsion had been made under Sub-Clause 63.1.
For the purpose of this Sub-Clause :
"corrupt practice" means the offering, giving, receiving or soliciting of
anything of value to influence the action of a public official in the
procurement process or in contract execution.
"fraudulent practice" means a misrepresentation of facts in order to
influence a procurement process or the execution of a contract to the
detriment of the Borrower, and includes collusive practice among
Tenderers (prior to or after Tender submission) designed to establish
Tender prices at artificial and non-competitive levels and to deprive
the Borrower of the benefits of free and open competition."
Sub-Clause 65.2
Special Risks
Sub-Clause 65.2 is amended to read as follows:
The Special Risks are the risks defined under paragraph (a), sub-
paragraphs (i) to (v) of Sub-Clause 20.4.
Sub-Clause 67.3
Arbitration
Delete in lines 6 to 8, of Sub-Clause 67.3 the words from "unless
otherwise" to "under such Rules" and add after the words "shall be
finally settled" in line 6 the following:
"in Kenya in accordance with the provisions of the Arbitration Act of
the Laws of Kenya or any other enactment replacing or modifying the
same for the time being in force, by a single arbitrator appointed by the
Chairman of the Engineer's Registration Board of Kenya on application
by either party."
Sub-Clause 68.1
Notice to
Contractor
Delete the text of Sub-Clause 68.1 and substitute the following:-
The Contractor shall maintain a physical and a postal address in the
Republic of Kenya, for the duration of the Contract.
The Contractor shall notify the Employer and the Engineer, in writing,
of the address of the office and of any change thereof and the
Employer and the Engineer shall not be bound to any change of
address until it has been so notified. The said offices shall be deemed
to be the domicile in Kenya of the Contractor and shall be kept open at
CHUKA UNIVERSITY
DECEMBER, 2016 Page 32
all reasonable hours during the above mentioned period to receive
instructions, notices, processes or other communications, unless
otherwise agreed in writing, between the Employer and the Engineer
and the Contractor.
All notices and other communications that are left against signature at,
or sent by registered post to, the said offices shall be deemed to be
validly served upon the Contractor. Every letter sent by registered post
shall be deemed to have arrived in due course of post until the
contrary is proved.
The Contractor shall also maintain an office at the Site which shall be
kept open during normal working hours to receive instructions,
notices, or other communications.
Sub-Clause 68.2
Notice to Employer
and Engineer
For the purposes of this Sub-Clause, unless otherwise stated in writing
by the Engineer, notices to both the Employer and Engineer shall be
sent to:
Vice Chancellor
Chuka University
P. O. Box 109 - 60400
Chuka.
Clause 69
Default of
Employer
In Sub-Clause 69.1, 69.4 and 69.5, substitute "Sub-Clause 60.8" for "Sub-
Clause 60.10".
Sub-Clause 69.1
Default of
Employer
In Sub-Clause 69.1 (a), substitute "56 days" for "28 days".
Delete Sub-Clause 69.1 (d).
Clause 70
Changes in Cost
and Legislation
Delete Clause 70 in its entirety and substitute the following:-
Sub-Clause 70.1
Price Increases
The rates and prices entered by the tenderer shall be deemed to
include for the cost of any price increases that may affect the Works
and which may occur during the validity of the Tender, and any
extended period of validity thereof, and during the execution of the
Works.
Sub-Clause 70.2
Subsequent
Legislation
If, after the date 28 days prior to the latest date for submission of
tenders for the Contract there occur in Kenya changes to any National
or State Statute, Ordinance, Decree or other Law or any regulation or
CHUKA UNIVERSITY
DECEMBER, 2016 Page 33
by-law of any local or other duly constituted authority, or the
introduction of any such State Statute, Ordinance, Decree, Law,
regulation or by-law which causes additional or reduced cost to the
Contractor in the execution of the Contract, such additional or reduced
cost shall, after due consultation with the Employer and the
Contractor, be determined by the Engineer and shall be added to or
deducted from the Contract Price and the Engineer shall notify the
Contractor accordingly, with a copy to the Employer.
Clause 73
Taxation
Sub-Clause 73.1
Foreign Taxation
The prices tendered by the Contractor shall include all taxes, duties
and other charges imposed outside Kenya on the production,
manufacture, sale and transport of the Contractor's Equipment, Plant,
materials and supplies to be used on or furnished under the Contract,
and on the services performed under the Contract.
Sub-Clause 73.3
Income Taxes on
Staff
The Contractor's staff, personnel and labour will be liable to pay
personal income taxes in Kenya in respect of such of their salaries and
wages as are chargeable under the laws and regulations for the time
being in force, and the Contractor shall perform such duties in regard
to such deductions thereof as may be imposed on him by such laws
and regulations.
Sub-Clause 74.1
Bribes
If the Contractor, or any of his Subcontractors, agents or servants gives
or offers to give to any person any bribe, gift, gratuity or commission
as an inducement or reward for doing or forbearing to do any action in
relation to the Contract or any other contract with the Employer, or for
showing or forbearing to show favour or disfavour to any person in
relation to the Contract or to any other contract with the Employer,
then the Employer may enter upon the Site of the Works and expel the
Contractor and the provisions of Clause 63 hereof shall apply as if such
entry and expulsion had been made pursuant to that Clause.
CHUKA UNIVERSITY
DECEMBER, 2016 Page 34
Sub-Clause 75.1
Termination of
Contract for
Employer's
Convenience
The Employer shall be entitled to terminate the Contract at any time
for the Employer's convenience after giving 21 days prior notice to
the Contractor, with a copy to the Engineer. In the event of such
termination, the Contractor:
(a) shall proceed as provided in Sub-Clause 65.7 and
(b) shall be paid by the Employer as per Sub-Clause 65.8.
Sub-Clause 77.1
Joint and Several
Liability
If the Contractor is a joint venture of two or more persons, all such
persons shall be jointly and severally bound to the Employer for the
fulfilment of the terms of the Contract and shall designate one of
such persons to act as a leader with authority to bind the joint
venture. The composition or the constitution of the joint venture shall
not be altered without the prior consent of the Employer.
Sub-Clause 78.1
Details to be
Confidential
The Contractor shall treat the details of the Contract as private and
confidential, save insofar as may be necessary for the purposes
thereof, and shall not publish or disclose the same or any particulars
thereof in any trade or technical paper or elsewhere without the
previous consent in writing of the Employer or the Engineer. If any
dispute arises as to the necessity of any publication or disclosure for
the purpose of the Contract the same shall be referred to the decision
of the Employer whose award shall be final.
Sub-Clause 78.2
Declaration against
Waiver
The condoning by the Employer of any breach or breaches by the
Contractor, or an authorized subcontractor, of any of the stipulations
and conditions contained in the Contract shall in no way prejudice or
affect or be construed as a waiver of the Employer's rights, powers
and remedies under the Contract in respect of any other breach or
breaches as aforesaid.
Sub-Clause 79.1
Repayment
Any payment for account of the Employer shall be made to
Vice Chancellor
Chuka University
P. O. Box 109 - 60400
Chuka.
WASTER WATER TREATMENT PLANT EVALUATION CRITERIA Bid evaluation will be in three stages namely: -
1. Mandatory requirements
2. Technical evaluation
3. Financial evaluation
4. Recommendation
A. Mandatory requirements
The mandatory conditions to be complied with are: -
a) Form of tender (properly filled)
b) Bid security with proper validity and as per sample provided
c) Class of registration with National Construction Authority
d) Tax compliance certificate
e) Must have completed a similar construction work of at least 10 million tender sum
f) Must have an annual turnover of at least 2 million (read from latest audited annual accounts)
g) The document must be properly serialised on all pages and total number of pages clearly stated
ii) A company shall fulfil all the seven conditions above in order to proceed to technical evaluation.
iii) Any company that does not fulfil any of the above conditions shall be disqualified from further
evaluation at this stage.
Technical evaluation
The bidder must attach the following, at the time of submission, in order to be considered technically responsive: -
1. Audited accounts of 2015 showing a fixed asset base of more than Kenya shillings five million
2. The (CV) Curriculum Vitae of the Lead Technical Expert including appropriate certificates showing relevant
technical qualification.
3. Completion certificates / recommendation for at least three similar project undertaken and completed successfully.
4. Attach proof of availability of at least two million Kenya shillings in liquid assets working capital (Bank credit line,
assets which can be quickly liquidated, bank statements etc.).
5. The brochures and / technical data for the lift will be analyzed in relation to:–
a) Adherence to minimum technical specifications for the Waste Water Treatment Plant attached here in.
b) All supporting calculations
c) Ease of availability of spares in the Kenyan Market.
d) Bidder must demonstrate how he will carry out the training of the client’s personnel for routine maintenance of the plant
e) Availability of qualified personnel for maintaining the machines.
f) The minor and major service intervals of the machines
g) Operation and maintenance cost of the supplier’s plant model (energy cost, chemical cost, and attendance)
h) Recommendations from satisfied users in the Kenyan market of the make and type of Waste Water Treatment
Plant recommended in the brochure.
The bidders who meet all the above five requirements will proceed to financial analysis.
C. Financial evaluation
The financial bids will be ranked from lowest to highest bid as per the total tender sum.
D. Recommendation The bidder with the lowest combination of initial investment; operation and maintenance cost
during the design life (20years) of the project will be recommended for award of this tender if the bid price is within the
prevailing market price.
Page 35
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List of Drawings
Drawing Number Description
MCE-153-SRL-001 Location Plan for the Sewer Reticulation and the Extended Aeration Waste Water Treatment Plant (Package).
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Figure 1-1: Location Plan for the Sewer Reticulation and the Extended Aeration Waste Water Treatment Plant (Package).
CHUKA UNIVERSITY
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PREAMBLE TO THE BILLS OF QUANTITIES
TECHNICAL DIRECTIONS
The preferred waste water treatment plant shall accommodate or have the following parameters:
Should be economical to space as practically possible, The design life of the plant should not be less than 30 years, Odors free treatment process, WWTP should handle a design capacity of 285 m3/day, but the plant should be
configured to operate at any discharge below this capacity i.e. should be adjustable to operate at a rate lower than design capacity,
The influent to the plant are from the following precincts
84m3/day from science biological and physics laboratories 36m3/day from administration block 110m3/day from students hostels 10 m3/day from food science laboratories Future projected load of 45m3/day
The supplier MUST provide us with all the design calculation justifying the sizes of various components of treatment works components i.e. blowers capacities, pumps capacity, sizes of chambers e.t.c.
Detailed schematic civil and structural drawings MUST accompany the quotation to enable us cost the civil and structural works,
Supplier MUST clearly state the operation and maintenance cost per annum when the plant is operating at full capacity, distinguishing chemical costs or any other associated cost,
Note the design of the plant will start from the outfall of our last manhole which will have invert depth of not more than 1 m
The location of the site is generally flat; however, the discharge point will be over 4 m lower than the site elevation hence the design of the effluent discharge system from the plant will utilize gravity.
The effluent should be dischargeable to the environment,
INFLUENT QUALITY The proposed effluent treatment plant was designed based on following types of influents: Estimate influent quality from similar case studies.
Sr. No. Parameter Unit Range 1 PH pH Scale 6.5 3 TDS mg/L 1520-1620 TSS mg/L 460 4 BOD (20C) mg O2/l 250-400
5 COD mg O2/l 400-800
(These are estimates and therefore they should not be used entirely to design the system, hence the supplier is expected to have prior experience in working in projects of similar condition)
CHUKA UNIVERSITY
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BILLS OF QUANTITIES FOR ELECTRO-MECHANICAL INSTALLATIONS # Description Unit Quantity Rate (Kshs) Amount
(Kshs) 1 Supply and install suitable equipments
housing
Nr 1
2 Supply and install suitable Blowers of the following characteristics Qmax=210 m3air /hr; Power 5 HP with its silencer
Nr 2
3 Supply and install suitable Blowers of following characteristics Qmax=545 m3air /hr; Power 10 HP with its silencer
Nr 2
4 Supply and install suitable blower drive systems
Nr 4
5 Supply and install suitable blower motor of 5hp 380v 3ph 50hz
Nr 2
6 Supply and install suitable blower motor of 10hp 380v 3ph 50hz
Nr 2
7 Supply and install control panels for the pumps which must include timers, Automatic alteration and flow control packages
Nr 1
8 Supply and install control panels for the blowers which must include timers and Automatic alteration
Nr 1
9 Supply and install suitable chlorinator model for chlorine tablet.
Nr 1
10 Supply and install galvanized 1.8mx 0.3m x0.9 m fine screen
Nr 1
11 Supply and install suitable package of MBBR media balls
Nr 1
12 Supply and install suitable MBBR media screens
Nr 6
13 Supply and install Air seal diffusers
Nr 120
14 Supply and install airlift surface skimmer
Nr 1
15 Supply and install sludge holding supernatant pump 1 HP, manual controlled
Nr 1
16 Supply and install 1HP, Qmax of 14.5m3/hr and Hmax 5.0m Sludge return pump, time controlled,
Nr 2
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# Description Unit Quantity Rate (Kshs) Amount (Kshs)
17 Supply and install 0.5 Horse power, Qmax of 7.13m3/hr and Hmax 5.0m Sludge return pump, time controlled
Nr 2
18 Supply and install all plumbing works including tees, bushes, elbows & sockets valves, GI pipes or any other suitable materials and any other fitting which will ensure the plant works efficiently to the Engineers satisfaction
Lump sum
1
19 Supply and install suitable effluent filtration unit with its media
Nr 1
20 Carry out complete biological and chemical test for monitoring the effluent with supervision from the Engineer
Nr 3
21 Supply Grease gun & grease and squeeze for maintenance tools
Nr 1
22 1 (one) year warranty and free Service of the plant. Rate to include for 3 months training of clients’ staff
%
23 Allow 10% contingencies for the whole amount
% 1 10
Total amount Exclusive of VAT
Total VAT Amount
Total amount Inclusive of VAT
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PERFORMANCE GUARANTEE: The Waste Water Treatment Plant should be capable of treating the above influent to the effluent quality acceptable for discharge into the environment, based on the third schedule of NEMA regulations. The electro-mechanical quote should be inclusive of all necessary government taxes, duties and levies including VAT in accordance with the laws of Kenya and the Client shall not reimburse any amount paid in this context. PAYMENT TERMS The payment schedule should be broken down into the following percentages:
% payable at time of placing the order
% payable upon delivery of plant to site.
% on testing and commissioning of plant
% payable at end of defects liability Period - 6months
This system will cost Kenya Shillings (amount in figures) (Amount in words) inclusive of VAT
NOTE:
The Extended Aeration Treatment Plant (Package) Contractor will only install the
ELECTRO-MECHANICAL components of these works while all other civil and structural
works will be done by the main contractor.
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TECHNICAL SPECIFICATIONS EXTENDEND AERATION WASTE WATER TREATMENT PLANT FOR CHUKA UNIVERSITY-THARAKA NITHI COUNTY
SECTION-01: BASIS OF DESIGN
The capacity/ rating of pumps and equipment etc. shall hold well for the capacity of 250-400
cum / day i.e. 250-400 KLD and shall be good for meeting the treated parameters
requirement as follows as per the NEMA and World Health Organisation (WHO)
regulations.
SECTION-02: SEWAGE TREATMENT PLANT
1.0 GENERAL
The sewage treatment plant (EATP) system outlined in this section specifies the system
design, manufacture, supply and installation of a standard Extended Aeration Wastewater
treatment (Package) System.
The work shall be carried out in a manner consistent with standards of specifications as
applicable. The Contractor shall take into account all site conditions in designing the system
and selecting the equipment. The Contractor shall be responsible for engaging an EATP
specialist to perform the system design and obtain approval from relevant Authorities and
Project Architect/ Project Architect’s representative. A qualified and experienced Engineer
shall be engaged for the system design, preparation of system proposal submission,
obtaining approval and site supervision.
The Contractor shall perform the system design based on the criteria/data and component
technical requirements specified in this section/drawings and the local Authorities’
regulation/requirement.
The Contractor shall furnish system which comprises products of manufacturers who have
designed and made these associated products for a period of at least five years.
The Contractor shall submit complete catalogue information, design calculation and
samples complete with full technical data and shop drawings for the entire system, test
certificates, etc. for acceptance prior to commencement of installation. The Contractor shall
submit analytical test reports of influent water samples and treated (effluent) water samples
after the commissioning or after the system is put into operation or as required by the
Project Engineer/their representative. The scope of work under this contract will include
assisting Project Engineer/their representatives to obtain necessary consent to operate from
local pollution control government authority.
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2.0 DESIGN CRITERIA
2.1 It shall be the Contractor’s responsibility to ensure the quality of the treated effluent to
comply with the NEMA regulations on waste water discharge requirement and the
following characteristics, whichever is stringent.
Estimate influent quality from similar case studies. Sr. No. Parameter Unit Range
1 PH pH Scale 6.5
3 TDS mg/L 1520-1620
TSS mg/L 460
4 BOD (20C) mg O2/l 250-400
5 COD mg O2/l 400-800
(These are estimates and therefore they should not be used entirely to design the system, hence the supplier is
expected to have prior experience in working in projects of similar condition)
2.2 Description of Process
The Sewage Treatment Plant shall be modular and packaged type installed on levelled
ground. The treatment process shall comprise the following stages:
Physical treatment: coarse bar-screening
Primary treatment: auto coarse bar-screen
Grease Trap Oil and Grease separation
Equalization tank: flow equalization with air Mixing
Flow measurement: flow meter
Nitrates removal Required
Biological treatment: MBBR as suitable to waste water quality
Final sedimentation: final settling tank with scraper
Disinfection: chlorination system : system with dosage control
Digester: aerobic digestion with individually retrievable air diffuser system.
Water reclamation: Partially tertiary filtration and sterilization for irrigation, cooling
tower makeup purpose and Flushing. Balance water quantity meeting irrigation
standards but with sterilization.
Sludge disposal: sludge chemical conditioning, disinfecting, dewatering and
disposal.
The Extended Aeration Treatment Plant (Package) Contractor will only install the
ELECTRO-MECHANICAL components of these works while all other civil and structural
works will be done by the main contractor.
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2.3 Performance Criteria of the Plant
Raw sewage will be brought into the last manhole of the sewerline. The Contractor shall
make arrangements to receive sewage from this point to the treatment plant for treatment
process.
The treatment plant shall be designed to treat the following basic characteristic expected in
the raw sewage. The waste water characters are based upon sampling done at project site
and for indicative purpose only. However, it will be entire responsibility of contractor’s to
reestablish the Wastewater characters and design system accordingly.
Description Details:
Estimated daily flow 285m3/ day
Discharge period 20 hrs./ day
PH 6.5-8.50
Influent BOD5 concentration 250-400 mg/l
Influent chemical oxygen demand 600-800 mg/l
Influent suspended solids(TSS) 200-600 mg/l
Oil and Grease 7-25 mg/l
E Coli Present
Faecal Coliform 600-1100 No/100ml
These are tentative indicative figures; however, as a specialist in the field, contractor may
envisage the raw sewage characteristic for waste water. It will be entirely contractor’s
responsibility to confirm the waste water characters.
Contractor to submit his confirmation on the treatment parameter considered as an
Annexure. The plant shall be capable of treating effluent to the following standards:
2.4 Process Description
The Main Contractor shall construct (civil and structural components) of Sewage
Treatment Plant to receive continuous sewage inflow at last manhole located near
EATP area as indicated on site plan. The ease of maintenance and operation is of
utmost importance in the design of Sewage Treatment Plant. The design of the
Sewage Treatment Plant shall be of suitable technology based; it can be installed
within the allocated space and shall be subject to the approval of the Project
Engineer/their representative
The plant will be housed on the ground, except for raw sewage and treated water
tanks. The required civil works like foundations etc shall be excluded in the scope
of work of EATP contractor.
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These will be general components, for the purpose of indication, but not limited to,
the EATP plant.
2.4.1 Inlet Screen Chamber
Raw sewage shall flow into the inlet screen chamber by gravity. Large solids
particles shall be intercepted by a fine step screen. A manual screen shall be
installed in parallel with the screw screen as a standby screen when the step screen
is under maintenance. It will not be part of the EATP contractor to execute but will
be designed by him.
Bar Screen
A bar screen having 20 mm opening shall be inserted in a bar screen chamber (in
RCC) at the inlet to the equalization tank. This screen will act as a guard and trap
any large objects which may otherwise block the pumps. The screenings shall be
removed by means of a manual rake arm for disposal. It will not be part of the
EATP contractor to execute but will be designed by him.
2.4.2 Aeration Tank
Sewage shall be retained in the aeration tank for a minimum of 24 hours and
subjected to biochemical oxidation by fine bubbles aeration. It will not be part of the
EATP contractor to execute but will be designed by him.
Equalization Tank
The screened effluent will overflow into an equalization tank. The equalization tank
is sized for a retention time of 6-8 hours. Since the generation of raw sewage is not
uniform (typically peaking in morning and evening hours), this tank buffers the
flow and ensures that the effluent inlet quantity and characteristics to the sewage
treatment plant is uniform.
To avoid settlement of solids and septicity in the tank, aeration is provided through
coarse bubble aeration grid consisting of perforated PVC pipes, individually
retrievable. The perforations are designated to give uniform air distribution through
the air grid. All plumbing works shall be part of the EATP contractor to design and
execute.
2.4.3 Clarifier Tank
The sewage after bio-oxidation shall enter the rectangular flat bottom sedimentation
tank where the sludge effectively settles to the tank bottom. The clear effluent shall
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weir into the chlorination chamber and/or ultraviolet chamber.
The activated sludge collected in the sludge tank shall be returned to the aeration
tank for further oxidation of the incoming organic matter by means of automatic
siphoning / pumping. Excessive sludge shall be wasted in the sludge holding tank.
Any scum formed on the surface of the clarifier tanks shall be returned to the
aeration tank by automatic siphoning / pumping. It will not be part of the EATP
contractor to execute but will be designed by him.
Chlorination Tank
Chlorine tablets shall be installed in the chamber and dissolve by the flowing
effluent. The effluent shall be retained in the baffle walled chlorine tank for a
minimum of 30 minutes for effective disinfection prior to discharge.
The equalization tank shall be designed to provide a minimum storage of 4 hours at peak
flow while pumping. Two submersible pumps (duty and standby) as per schedule shall be
provided with level switch control and automatic cut-in of the standby unit.
An aeration system similar to the extended aeration tank shall be provided for mixing and
aerating the sewage.
It will not be part of the EATP contractor to execute but will be designed by him.
3.5 Sludge Collectors
The sludge collectors serve to scrap the settled sludge to the sludge pump pit and a skimmer shall collect the scum. Each shall be of mechanical drivers for full automatic operation. All components such as chain, sprocket, etc. inside the tank shall be made of non-metallic material. It will not be part of the EATP contractor to execute but will be designed by him.
3.6 Sewage Pumps
Working and standby sewage pumps shall be provided. Contractor shall provide the
pumping arrangements for sewage collected near collection chamber near EATP. Each shall
be of submersible type guide base to facilitate case of removal, lift chain and automatic
discharge connection. Pump casing and impeller shall be of cast iron material. Shaft shall be
of stainless steel material. All sizing of pumps shall be part of the EATP contractor to design
and execute.
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3.8 Final Settling Tank
Settling tanks shall include baffles to prevent short circuiting. Sludge withdrawal shall be
by means of rotating sludge collectors. Four submersible sludge pumps shall be installed in
the hopper bottom at inlet side of the settling tank for periodic sludge removal. It will not
be part of the EATP contractor to execute but will be designed by him
3.9 Tertiary Treatment
The tertiary treatment plant shall comprise of the pressure sand filters, activated carbon
filters and out to inward entry sewage water designed membrane filtration system. This
shall be sized to accommodate 100% of the effluent discharge flow rate and shall achieve
the performance as outlined and described in Design Criteria.
Details of the equipment layout proposal shall be submitted for review by the Project
Manager with tender documents.
The filters will be added in phases as demand arises and system shall be capable to add
with additional tertiary filtration units without disturbing the existing operations of system.
All sizing of tertiary treatment system shall be part of the EATP contractor to design and
execute.
3.11 Electrical Control
The operation of the treatment process shall be of semi-automatic. A completely assembled
and prewired control panel with mimic diagram consisting of weatherproof cabinet shall be
furnished. The control panel shall contain all metering and status indicators, motor starters,
program timbers, on-off-auto change-over switches and duty selectors for equipment.
Proper control sequence shall be designed according to system requirement and
manufacturer standards.
All sizing of electrical system shall be part of the EATP contractor to design and execute
3.12 Other Equipment
Any other necessary accessories, such as buffer, riser, scrum removal devices, partition,
control panel, collection devices, etc. for all the tanks and pumps (where necessary) shall be
provided in order to provide a fully working systems. All other necessary equipment which
fall under elecro-mechanical shall be part of the EATP contractor to design and execute
3.13 Valves
The Contractor shall supply and install all isolating valves and control valves as indicated
on the drawings and as required for the proper and efficient operation and maintenance of
the entire systems. All valves supplied shall be suitable for the working pressure and test
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pressure of the system as specified elsewhere in this specification. Regulating valves shall
be of similar materials as that specified for cast iron gate valves.
All regulating valves shall be lock shield type.
All valves shall be full line size.
Each valve shall have a purpose made reference number plate for label engraved or
stamped indicating the manufacturer’s catalogue number, pressure and temperature
ratings. Valves shall be arranged so that clockwise rotation of the spindle will close the
valve. Furnish all valves and accessory materials necessary in the piping whether or not
shown on drawings as flows. All valves shall be packed with an approved packing and
threads shall be coated with oil and graphite. Packings should be replaced when found
deteriorated on site. Where possible locate all valves at convenient positions of operation
from the floor with valve stems upright. Valves that are flanged shall have flanges to the
table specified for the pipework. Plastic or metal plates (rustless) shall be provided to
indicate the open / close status as well as the use of each valve in the pump and tank rooms.
All valves installation shall be part of the EATP contractor to design and execute
4 INSTALLATIONS
The Contractor shall check the associated civil work prior to the installation of any item of
machinery and carry out all necessary additions alterations as necessary at no extra cost.
The machinery shall be accurately installed to correct dimensions, alignments, levels, etc.,
all as indicated on the final drawings. The machinery shall be mounted on flat steel packing
pieces of thickness suitable to take up variations in level of the concrete foundations.
Suitable packing pieces shall be located adjacent to each holding down bolt and shall be
properly bedded by grinding the concrete surface to a smooth, level finish. The machinery
shall be aligned and leveled and the nuts of the holding down bolts tightened with a
spanner of normal length. The base plates shall be packed with grout after the machinery
has been run and checked by the Project Manager for stability and vibration. Installation
shall include the provision and fixing of all necessary holding down bolts, washers, nuts
etc. All equipment and materials of the same type shall be products of the same
manufacturer. All similar items of plant and their component part shall be completely
interchangeable. Spare parts shall be manufactured from materials similar to the originals
and shall fit all similar items of plant. Where machining may be needed before fitting
renewable parts, the machining fits with their tolerance shall be shown on the drawings
accompanying the instruction manuals. All motors and/or revolving parts shall be truly
balanced both statically and dynamically so that when running at normal speeds and any
load up to the maximum there shall be no significant vibration due to lack of balance. All
parts which can be worn or damaged by dust shall be totally enclosed in dust-proof
housings.
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5. MAINTENANCE FACILITIES
Permanent work platform and catwalk shall be the Contractor for access to elevated
equipment. The catwalk and platform for access shall allow a minimum width of 600mm.
Catwalk to maintenance platform shall be provided with railings and guards designed for
safe movement of personnel in a restricted space including provision for gaining access and
to accommodate maintenance personnel. Hand railing and guards shall be provided by the
Contractor for all concrete tanks to allow safe movement of personnel. Permanent I-beams,
lifting eyes, etc. shall be provided by the Contractor over major equipment which requires
lifting for overhaul and maintenance, if necessary. Waterproof power sockets required for
servicing shall be provided by the Contractor. The number and locations shall be proposed
by the Contractor and approved by the Project Manager / Engineer. Power supply to these
sockets shall be taken from control panel of the sewage treatment system. The design of all
permanent work platforms, hand rails, etc. shall be submitted to the Project Manager /
Engineer for approval. The loading and fixing method of lifting facilitate shall also be
submitted to the Project Manager / Engineer for approval and checking within 4 weeks on
award of Contract or receipt of letter of intent.
6. TESTING
The performance of the system shall be demonstrated by taking hourly samples of the raw
sewage and final effluent over a twelve hour period. The sample shall be taken at periods
approximately the flow rates specified by the plant. The sample shall be combined and a 5-
day BOD shall be run, the results of which must verify the capacity of the treatment plant
prior to acceptance.
7. TRAINING
Provided training facilities courses to ensure that the Project Engineer/their representative’s
staff associated with the project may acquire full knowledge and appreciation of all aspects
of the design, day-to-day operation, breakdown and routine maintenance, and fault
diagnosis of all plant, equipment and systems.
Training to the Project Engineer/their representative’s staff shall be held as appropriate at
the Contractor’s or manufacturer’s premises and on site. A detailed syllabus for each of the
training courses specified or proposed and the timing of the courses shall be submitted for
approval. The Contractor shall recommend the desirable qualifications and experience of
the trainees to optimally benefit from the courses. The plant operation training shall be
done for minimum period of 7 calendar days, at the time of commissioning and at the time
of handing over of plant. The Contractor shall be deemed to have included in his tender
price the cost of providing training facilities as specified.
In addition to the above, the Contractor shall submit to the Project Manager a list describing
such other spares and special tools, their number, price and where appropriate the
anticipated frequency of replacement as soon as possible along with minimum set of
mechanical, electrical spares and chemicals required.
CHUKA UNIVERSITY
DECEMBER, 2016 Page 52
SECTION-3: TESTING, COMMISSIONING AND HANDING OVER
1.0 GENERAL
The entire works included in this Contract shall be fully tested in stages as the work
proceeds and on completion of work as applicable. The plant testing will be primarily done
at manufacturing unit prior to dispatch and then on site. The Contractor shall provide
during normal working hours, all necessary labours, instruments, equipment, materials,
fuel, power and maker's representatives, to carry out such tests as may be necessary to
satisfy the Project Engineer so that the installation meets the requirement and intent of the
Specification as well as such tests required by Regulatory Authorities.
All tests shall be made in the presence of the Project Engineer/ their representative and/ or
any inspecting authority. At least seven working days’ notice in writing shall be given to
the inspecting parties before performing any test. Three copies of all test results shall be
submitted to the Engineer in A4 size sheet paper within two weeks after completion of the
tests. Tests described hereinafter and including all tests prescribed by the Authority having
jurisdiction shall be carried out. Any tests proved unsatisfactory shall be repeated to the
satisfaction of the inspecting parties.
The Contractor shall provide skilled technicians/engineer to commission the plant and
associated controls to the satisfaction of the Project Engineer/their representative. The
technicians/ engineers will be required to demonstrate the correct procedures in starting
and stopping the plant, running the various items of equipment under automatic and
manual control and the correct maintenance of the plant. Wastewater flow rates of all
equipment shall be adjusted to design conditions. Complete results of adjustments shall be
recorded and submitted.
2.0 ON-SITE TESTING AND COMMISSIONING
The Contractor shall start up, operate, test and adjust the systems in accordance with the
agreed programme. The setting shall be supervised by the manufacturer's representative,
who shall remain on site until the equipment is operating satisfactorily and accepted by
Project Engineer and/or their representative. The Contractor shall advice and co-ordinate
with the manufacturer's representatives so that all testing is carried out according to the
agreed programme.
The whole installation shall be given the tests to bring the systems into running order. The
Project Engineer/their representative shall be given reasonable notice together with a copy
of recorded test results, generally not less than seven (7) days, regarding the nature of tests,
the time and location. Acceptance tests will only be witnessed by the Project Engineer/their
representative when the submitted tests results are found satisfactorily. All instruments,
tools, material and labour required to perform these tests shall be provided by this
Contractor. Before the tests are carried out, the Contractor shall remove connected
equipment and components which are liable to damage under test, and shall provide and
fix all the necessary gauges, blanking flanges, etc.
CHUKA UNIVERSITY
DECEMBER, 2016 Page 53
Prior to the system start-up, the following inspection, tests and pre-commissioning
treatment shall be carried out by the Contractor:
A. Tanks and Level Switches
Check sides and edges of sectional tanks for distortion. The tanks shall be thoroughly
cleaned with water and drained before mains supply will feed in.
Also before mains supply will feed in, the level switch shall be simulated for the various
cut-in and cut-out settings.
B. Pressure Switches
The testing equipment arrangement for pressure switches and pressure gauges shall be as
shown on the drawings or of an approved equivalent. The pressure gauges to be tested
shall be connected as shown on the drawing in lieu of the pressure switch.
The gauges to be tested shall be regarded acceptable when the pressure readings of all three
gauges are the same throughout the jacking pressure range varied by applying the hand
pump.
C. Hydrostatic Tests
All parts of the water circuit shall be filled with water before hydrostatic pressure testing,
and pump running tests for verification of pressure and flow rate, are conducted.
The hand jacking pump shall be applied to increase the system pressure to 2 times the
working pressure or 1.5 times the working pressure plus 3.5 bar whichever is the lower but
in any case not less than 7 bars. The pressure shall be maintained for a period not less than
24 hours.
Where any section of pipework or equipment is found to be unable to withstand the
maximum pipework test pressure, it shall be isolated during the pipework test then that
section of pipework or equipment shall be made good and re-tested at the appropriate test
pressure.
The working pressure for various systems shall be as shown on the drawings.
Drains shall be hydrostatically tested to a water head of 1.2 m at the high end and not more
than 2.4 at the low end and shall show no appreciable loss of water after elapse of two
hours.
In every test, water used shall be left in the pipes until they are covered with earth or other
trench filling material to a depth of at least 1 m over the top of pipes and until permission is
given by the Project Engineer/their representative for the water to be released. If after the
Project Engineer/their representative has approved the sewer or pipeline and has given
CHUKA UNIVERSITY
DECEMBER, 2016 Page 54
permission for the trenches to be refilled the pipes become damaged and loses water from
any cause and/or admit subsoil water, the Contractor shall uncover the pipes and make
good the defect made good and the pipes retested as before and all at the Contractor's
expense.
D. Cleaning, Flushing and Pre-Treatment
Prior to start-up and hydraulic testing, the Contractor shall clean the entire installation
including all fitments and pipework and the like after installation and keep them in a new
condition. All pumping systems shall be flushed and drained at least once through to get
rid of contaminating materials.
All pipes shall be rodded to ensure clearance of debris, cleaning and flushing shall be
carried out in sections as the installation becomes completed. All strainers shall be
inspected and cleaned out or replaced.
When the entire systems are reasonably clean, a pre-treatment chemical shall be introduced
and circulated for at least 8 hours. Warning signs shall be provided at all outlets during pre-
treatment. The pre-treatment chemical shall:
Remove oil, grease and foreign residue from the pipework and fittings;
Pre-condition the metal surfaces to resist reaction with water or air;
Establish an initial protective film;
After pre-treatment, the system shall be drained and refilled with fresh water and
left until the system is put into operation.
Details and procedures of the pre-treatment shall be submitted to the Project
Engineer/their representative for approval.
E. Electrical Tests
Electrical insulation tests earth electrode resistance test and cost amenity test shall apply to
bus bars, isolators and other equipment and wiring where applicable. A 500V DC
instrument shall be used to check the insulation resistance.
The reading shall not be less than 1 mega-ohm in all instances. Function simulation tests
shall be performed to ensure that the systems have been installed to the control
requirements as described in the Specification therein.
F. Pump Drives
The direct coupling of the pump drives shall be dismantled before the pump motor control
panel is energized. The Contractor shall demonstrate to the Project Engineer/their
representative of acceptable clearances of the coupling alignment for ensuring satisfactory
power transmission. The coupling shall not be re-mated again till the correct motor rotation
has been demonstrated with power drawn from the energized pump motor control panel.
CHUKA UNIVERSITY
DECEMBER, 2016 Page 55
G. Pump Operating Test
The Contractor shall ensure to the satisfaction of the Project Engineer/their representative
that the installation or portion thereof which has been set to work complies with all
requirements including the following:
That the plant and apparatus shall be of robust construction and of capacity for the duty
specified.
That all valves, switches, controls and the like are properly regulated and capable of proper
operation and in the case of valves are capable of being shut-off.
That all apparatus shall be silent.
That all instruments are correctly calibrated and read accurately.
That all services are tested in accordance with the details of the relevant clauses of this
Specification.
3 STATUTORY AUTHORITIES' TESTS AND INSPECTIONS
As and when notified in writing or instructed by the Project Engineer/their representative,
the Contractor shall submit shop drawing and attend all tests and inspections carried out by
NEMA and other Statutory Authorities, and shall forthwith execute free of charge any
rectification work ordered by the Project Engineer/their representative as a result of such
tests and inspections where these indicate non-compliance with Statutory Regulations.
The Contractor shall be responsible for the submission of all necessary forms and shop
drawings to the Statutory Authorities which shall conform in layout to and kept by these
Authorities.
The submission shall comply with the requirements set forth in the current Codes of
Practice and circular letters of the Statutory Authorities. The shop drawings to be submitted
shall be forwarded to the Project Engineer/their representative/Structural consultant for
checking before submission. The Contractor shall allow for at least two submissions of
complete sets of shop drawings to the Authorities, one to be made within six months after
the award of the Contract but not less than six weeks before the inspection. The Project
Engineer/their representative may at his discretion instruct the Contractor for additional
submissions to the Regulatory Authorities whenever necessary.
The Contractor shall notify the Project Engineer at least seven days in advance of his
application for Regulatory Authority tests and inspections. On receipt of a confirmed date
for test and inspection the Contractor shall inform the Project Engineer/their representative
without delay.
CHUKA UNIVERSITY
DECEMBER, 2016 Page 56
4 COMMISSIONING
When the various installations have been completed and the preliminary commissioning
checks carried out, the Contractor shall set to work, regulate and calibrate all system in the
entire installation. Special attention shall be paid to the following items:
That all valves, switches, controls, etc. are regulated and capable of proper operation and in
the case of isolation valves that they are capable of tight shut off.
That all apparatus is silent in accordance with the requirements of this Specification.
That all instruments are correctly calibrated and read accurately.
That all services are tested in accordance with the details in the relevant clauses of this
Specification.
Operate pumps, pressure reducing sets, etc. to ensure that all control systems are
functioning correctly and are properly set, sequenced or interlocked.
5 FINAL ACCEPTANCE TESTS
Following commissioning and inspection of the entire installation, and prior to issue of the
Completion Certificate, the Contractor shall carry out final acceptance tests in accordance
with a programme to be agreed with the Project Engineer/their representative. Should the
results of the acceptance tests show that plant, systems and/or equipment fail to perform to
the efficiencies or other performance figures as given in this Specification, the Contractor
shall adjust, modify and if necessary replace the equipment without further payment in
order that the required performance is obtained. Where acceptance tests are required by
the relevant Authorities having jurisdiction, these tests shall be carried out by the
Contractor prior to the issue of Completion Certificate to the acceptance of the Authorities.
Contractor will extend all technical help and do liasoning on behalf of Project Engineer to
obtain necessary permit to operate / Consent to operate from authorities. The fees required
will be paid by Project Engineer/ their representative directly. Though payments are made
by Project Engineer, it will be entire responsibility of contractor’s to obtain Consent to
Operate from respective authorities.
6 REJECTION OF PLANT
Any item of plant or system or component which fails to comply with the requirements of
this Specification in any respect whatsoever at any stage of manufacture, test, erection or on
completion at site may be rejected by the Project Engineer/their representative either in
whole or in part as he considers necessary/appropriate.
Adjustment and/or modification work as required by the Project Engineer/their
representative so as to comply with the Authority's requirements and the intent of the
Specification shall be carried out by the Contractor at his own expense and to the
satisfaction of the Authority/Project Engineer/their representative.
CHUKA UNIVERSITY
DECEMBER, 2016 Page 57
After works have been accepted, the Contractor may be required to carry out assist in
carrying out additional performance tests as reasonably required by the Project
Engineer/their representative/Project Engineer.
7 WARRANTY AND HANDOVER/ DEFECTS LIABILITY PERIOD
The Contractor shall warrant that all plant, materials and equipment supplied and all
workmanship performed by him to be free from defects of whatsoever nature before
handover to the Project Engineer/their representative. The designed performance of plant
shall be monitored for minimum period of 3 months. The defects liability period of 12
calendar months will commence from the date of receipt of approval from concerned
authorities. The contractor shall handover all guarantees/ warrantees of all equipments
used in the plant and or transfer all such warrantees/guarantees on the name of Project
Engineer.
It will be obligatory on part of contractor to extend all exhausted guarantee/warrantee for
further period of minimum 3 years, from date of obtaining authority approval in writing, at
no extra cost to project Engineer.
Defects liability period will be considered as completed satisfactory, only after getting plant
performance within prescribed design limits, for minimum plant up time of 85% of 1
calendar year for entire operations during defects liability period.
Any deficiency noted during defects liability period or part thereof, will automatically
extend the defects liability period equal to duration for which plant performance was not
met with, at no extra cost payable to contractor on any account.
8. HANDING OVER OF DOCUMENTS
All testing and commissioning shall be done by the Contractor to the entire satisfaction of
the Project Manager and all testing and commissioning documents shall be handed over to
the Project Engineer/their representative. The Contractor shall also hand over all
maintenance and operation manuals, all certificates and all other documentation as per the
terms of the contract to the Project Engineer/their representative.
9. OPERATION AND MAINTENANCE OF PLANT
The cost of operations and maintenance including mechanical, electrical spares, chemicals
required etc as and when required along with necessary manpower on 24 hours basis,
during the defects liability period of 1 calendar year or any extension thereof, shall be
included in the cost and no extra cost will be payable to contractor on any account thereof.
Contractor shall indicate plant operation and maintenance cost along with routine
mechanical, electrical spares and chemicals including round the clock manpower for plant
operation for period of 3 years, to be counted from date of satisfactory completion of defects
CHUKA UNIVERSITY
DECEMBER, 2016 Page 58
liability period. The Project Engineer will enter in to plant operation maintenance contract
on successful completion of defects liability period at the rates quoted now.
The maintenance amount so quoted and approved will be payable every half yearly in
advance at the beginning of half year period on receiving necessary supporting invoice
from contractor. Contractor shall provide list of optimal spares for the pant, that to be kept
for entire period for plant maintenance, which will be maintained by him as optimal
inventory at plant site at no extra cost to Project Engineer.
CHUKA UNIVERSITY
DECEMBER, 2016 Page 59
DESIGN CALCULATIONS for Chuka University Extended Aeration Process
Capacity: Average Flow 0.285 MLD
S No Description of Parameter Value Unit Requirement
Quantity of Sewage Generated 285,000.00 Lpd
0.29 MLD
285.00 Cum/day
Raw Sewage Characteristics
1 Average Sewage flow entering the treatment plant 285,000.00 lpd
Assumed Peak Factor 3.00
2 Peak Sewage flow entering the treatment plant 855,000.00 lpd
3 COD 400 - 800 mg/Lt
4 BOD 300.00 mg/Lt
5 TDS 1520-1620 mg/Lt
6 TSS 460.00 mg/Lt
7 pH 6.50
1 Inlet Chamber
Quantity of Flow (Ave) 285.00 Cum/day
Peak Flow 855.00 Cum/day
0.01 Cum/Sec
Assumed Detention period 10.00 sec
Volume of the Inlet Chamber 0.10 Cum
Assumed Depth of flow 0.30 m
Area Required for Inlet Chamber 0.33 Sq.m
Assumed Length to Breadth Ratio 1.00
Breadth of the Tank 0.60 m
length of the Tank 0.60 m
2 Screen Chamber (Fine Screens)
Peak Design Flow 0.01 Cum/s Assume Size of the screen flats of size having a
thickness of 10 mm and a width of 50 mm (CPHEEO
page no 201)
Assume Clear spacing between bars, o 6.00 mm 20-50mm, pg.201 of CPHEEO Manual
Velocity ahead of screen (Va) 0.60 m/sec pg. 202 of CPHEEO Manual
Area of Screen Channel, A= (Q/Va) 0.02 m2
Keeping Side Water Depth 0.60 m
Width of each screen channel, W 0.30 m
Water depth upstream, ha = A/W 0.07 m
t 0.01 m
Number of openings in chamber, W = X.o + (X - 1).t where , X
= No. of Opening ; o = Clear Space between bars ; t =
Thickness of flat
19.00 no
Total width of opening, Ws =x*o 0.11 m
Assume Angle of inclination 45.00 Degree
Assumed Detention Period in the Screen channel 3.00 sec
Assume Length of the screen chamber 1.80 m
Inclined height of the screen, H1 0.09 m
say
Velocity through the screen, Vs= Q/H1*Ws 0.92 m/sec
Head loss thru screen in normal condition, h1=0.0729(Vs2-Va2) 0.04 m less than 0.15 m hence ok
Head loss on 50% clogging h1=0.0729(2*Vs2-Va2) 0.10 m less than 0.3 m hence ok
Water Depth downstream Hb, (Za-Zb)+Va2/2g-Vs2/2g+Ha-
Headloss thru screen in normal condition
0.00 m
Water Depth downstream Hb, (Za-Zb)+Va2/2g-Vs2/2g+Ha-
Headloss thru screen in clogged condition
-0.06 m
3 Equalization Tank (Collection Chamber )
Peak Design Flow 855.00 Cum/day
Assumed Detention period 2.1 hours
Volume of the Tank 74.8125 Cum
Assumed Depth of Liquid column 2.5 m
Area required for the equalization tank 29.925 Sq.m
No. of Tanks Proposed 2
area required for each equalization tank 14.9625 Sq.m
Length to Breadth ratio 1
Breadth of the tank 4 m
Length of the tank 4 m
Provide 2 No. Equalization tanks each measuring 4.05m by 3.95m by 3.4m high SWD + 0.3M Freeboard
Design of Sewage Treatment Plant
Guidance:Yellow cells are input information to be suitably filled. Green cells are to be reviewed and modified/updated.
Provide the Dimension of Inlet Chamber as 0.6 m x 0.6 m x 0.3 m SWD + 0.3 m Freeboard
Provide the Dimension of Screen Chamber (Fine Screens) as 1.8 m x 0.3 m x 0.6 m SWD + 0.3 m Freeboard
CHUKA UNIVERSITY
DECEMBER, 2016 Page 60
Mixing Arrangements
Assumed BOD reduction in the tank 15% Percent
Incoming BOD of Raw sewage 300.00 mg/L
BOD to be reduced 45 mg/L
BOD Load 38.5 kg/day
Oxygen required to remove BOD load 2 kg/kg of BOD
Oxygen required 77.0 kg/day
3.21 kg/hr
Actual Air Required 201.96 Cum/hr
Provide Corse bubble aeration grids for 210.00 cum/hr
4 Raw Sewage Pumps
No. of pumps - (1W+1SB)
Type of Pumps - Submersible/Horizontal Centrifugal
Average flow 285.00 Cum/day
Number of working hours 20 hrs
Flow Capacity of Pump required 14.25 Cum/hr
Proposed pumps 2 numbers (1W + 1SB), flow per Pump14.25 Cum/hr
3.96 lps
Head required 5.00 m
HP required for pump 1.00 hp
5 Aeration tank
No of Tanks 1
Flow - completely mixed
Q- per tank 285.00 cum/day
BOD 255.00 mg/Lt
MLSS 2500.00
Type Aeration - Diffuser type fine bubble
Blowers - 1.00 ( 1W+1SB)
F/M assumed 0.12
Volume of the tank 242.25 Cum volume of tank as per 13.6 page 226
Add additional volume of 25% for sludge recycle 60.56 Cum
Total volume of tank 302.81 Cum
Hydraulic Detention Time 0.02 day
Depth of the tank 3.40 m
Area of the Tank 89.06 Sq.m
Area for each tank 89.06 Sq.m
Assumed Breadth to Length Ratio 1.00
width of the tank 9.5 m
Length of tank 9.4 m
6 Blower capacity
BoD load 72.68 kg/day
3.63 kg/hr
Oxygen Required for 1 kg BOD removal 2.00 kg
Theoretical Oxygen 7.27 kg/hr
Actual requirement of air 343.32 cum/hr
Total Air Requirement 545.50 Cum/hr
fine bubble diffuser assumed to inject oxygen of 5.00 cum/hr
Provide Membrance diffuser for aeration tank 109 No.
Provide 2 Blowers of capacity of 10 Horse power (1W+ 1
SB) 545.50cum/hr
for each tank
Sludge Volume Index assumed 100.00 Page 235-SVI 80 to 150
Sludge Recirculation Qr/Q=Xt/((10 6̂/SVI)-Xt) 0.33 table 13.1 page 235 or taking SVI 100
Volumetric loading rate 0.24 kg/cum
Xt V = 605625.00
ay Q (Yo – Ye) qc/(1 + ke qc) 66975.00 equation 13.7 page 227
0.11
0.05
Hydraulic Mean Cell Residence Time 19.77 days
Assumed Reduction in the Aeration Tank 95.00 %
Outlet BOD from the Aeration tank 12.75 mg/L
Provide 2 Blowers of capacity of 10 Horse power (1W+ 1 SB)
Provide 2 No. (1 working & 1 stand by), 33 URAI( 210m3/hr; 5 Horse power) Blowers
Provide 2 No. (1 working & 1 stand by), 1.0 Horse Power sludge pump
Provide 5 No. Aeration tanks each measuring 1.92m by 3.95m by 3.4m high SWD + 0.3M Freeboard and 5 No. Aeration tanks each measuring
1.92m by 3.75m by 3.4m high SWD + 0.3M Freeboard
CHUKA UNIVERSITY
DECEMBER, 2016 Page 61
7 Secondary clarifier
No. of Tanks 1
Average Flow in each tank 285.00 cum/day
SOR 25.00 Cum/Sqm/day
Table 12.1, but it is 8-15 for average flow and 25-35 for
peak flow for extended aeration
SWD 2.00 m
table 12.1, it is 3.5-4.5 m for extended aeration,
although para 12.4.2.5 give depth 2 m in vertical flow
tanks
Solid conc. In settled sludge -% 0.8 to 0.9 %
Withdrawal frequency - continuous
Area Required for the Tank 11.40 Sq.m
Length Required for Secondary Settling Tank 2.39 m
Assumed Detention Period 2.00 hrs 1.5-2 hrs as per table 12.1
23.75 Cum
Depth of the Clarifier assumed 2.00 m
Area of the Clarifier 11.88 Sq.m
Surface Loading Rate 24.00 Cum/Sq.m/day
Assumed BOD reduction in Clarifier 10.00 %
Outlet BOD from Clarifier 11.48 mg/L
8 Return Activated Sludge /Excess sludge pumps
Type of Pumps - Centrifugal
No. of pumps 1 (1W+1SB)
Assumed return flow 50.00 %
Return sludge Pumps 142.50 Cum/day
Operating hours 20.00
Capacity of pump required 7.13 Cum/hr
1.98 lps
Head required 5.00 m
Power requirement for the Pump 0.50 Hp
9 Treated Sewage Sump/Chlorination Chamber
Assumed Detention time 30.00 Minutes
Average Flow 285.00 Cum/day
Volume of the tank 5.94 Cum
Provide a depth of tank as 1.95 m
Length to breadth ratio 2.00
Area of the Tank 3.04 Sq.m
Rectangular length of the tank Size 3.50 m
Provide 2 No. (1 working & 1 stand by) 0.5 Horse power, Qmax of 7.13m 3/hr and maximum head of 5.0m Sludge return pump
Provide the Dimension of Treated Sewage Sump/Chlorination Chamber as 1.6 m x 3.1 m x 1.95 m SWD + 0.3 m Freeboard
Provide 2 No. secondary Clarifier each measuring 1.92m by 3.95m by 3.4m high SWD + 0.3M Freeboard and 2 No. secondary Clarifier each
measuring 1.92m by 3.75m by 3.4m high SWD + 0.3M Freeboard