Report on the Field Visit 10Dec2008 (Final report)
Report on the Field Visit
Da Nang City, Vietnam
PROPOSED TWINNING PROGRAM
Manila Water International Solutions (MWIS),
Danang Water Supply Company (DAWACO)
and Environmental Cooperation-Asia (ECO-Asia)
November 17-18, 2008
Submitted by:
Vilma Annabelle Deray
Melissa Adriano
Report on the Field Visit 10Dec2008 (Final report)
Table of Contents
1. Introduction 2. Brief Description of Project Area
3. Findings and Analysis
a) Raw Water Source b) Treatment Plant c) Distribution d) Others
4. Conclusions/Recommendation 5. Moving Forward
Report on the Field Visit 10Dec2008 (Final report)
Report on the Field Visit to Da Nang City November 17-18, 2008
INTRODUCTION
The Environmental Cooperation-Asia (ECO-Asia), a project of the United States Agency for
International Development (USAID) Regional Development Mission/Asia (RDM/A) has
initiated a Twinning Program involving the Manila Water Company, Inc. (MWCI), a Utility
Company in the Philippines that provides water and wastewater services to the East Zone of
Metro Manila and Da Nang Water Supply Company (DAWACO), a government corporation
that provides water supply services to the city of Da Nang in Vietnam.
The twinning program is a strategy of ECO-Asia wherein a utility partners with another utility
to share its best practices, core skills and competencies with the objective of: (1) increasing
access to safe drinking water and sanitation, and (2) promoting regional dialogue and
cooperation to share and replicate best practices. ECO-Asia facilitates the arrangement and
transfer of best practices, expertise and technology through peer-to-peer exchanges.
The focus of the proposed Twinning Program between MWCI and DAWACO is on improving
DAWACO’s water quality management processes, especially on maintaining adequate
chlorine residual levels in the water supply distribution network, to safeguard against public
health hazards for at least 2,000 household customers. DAWACO is planning to improve its
water quality management program under the Water Safety Plan framework led by the World
Health Organization (WHO).
As a first step to the Twinning Program, ECO-Asia has scheduled a field visit of MWCI
representatives to Da Nang in November 17-18 with the following objectives:
1. Introduce MWCI to DAWACO operations and staff (and vice versa)
2. Assess current DAWACO operations by MWCI to understand its water quality
management constraints through field visits/discussions, and
3. Begin discussions on MWCI-DAWACO partnerships to assist DAWACO in effectively
managing water quality and safeguarding public health.
The succeeding report provides an account of the two-day visit to Da Nang City by
representatives from MWCI. Since the visit was brief, this report will only provide a
preliminary assessment on the current water supply condition of DAWACO as observed,
gathered and analyzed by the Manila Water representatives through discussions with
DAWACO and ECO-Asia’s counterpart team. Moreover, it will focus particularly on the Cao
Do water supply facilities that include the raw water source, water treatment plant and its
service area affected by the water quality problem.
Report on the Field Visit 10Dec2008 (Final report)
BRIEF DESCRIPTION
The Project Area. The city of Da Nang is the 4th biggest city in Vietnam next to Ho Chi Min,
Hanoi and Haipong. It is located in the central region about 764km south of Hanoi and
964km south of Ho Chi Min. It has an area of 1,256km2 and an estimated population of
804,000. The city is well-developed and commercialized and is composed of eight (8)
districts. It has diverse geographical features— rivers, mountains, seas, etc. Main industries
include seafood export, tourism, factories and manufacturing plants. Infrastructure facilities
comprise an international airport, port facilities, railways and road networks.
Water Supply Scenario. DAWACO is a government company that provides water supply
services to the city. It supplies 60% of the total water demand
through the operation of three (3) water treatment plants (WTP)
located in various areas of its service area. The WTPs produce a
treated volume of water at 120 million liters per day (mld) or
120,000 cubic meters per day (M3/day). The current water source of
the two (2) treatment plants is the Cam Le River while the other
treatment plant utilizes the water source from a spring.
The total served population is about 453,000 with an
estimated total number of 109,000 service connections.
Consumption per capita as provided is at 150 liters/day,
which is comparable to Manila Water’s average
consumption in its service area.
On the distribution side, DAWACO has more than 2,000
kilometers of pipes which are relatively new in some areas.
Pipe sizes vary from 100mm diameter to 900mm∅. The average Non-Revenue Water (NRW)
is at 35.5% for 2008 but latest figure shows a marked decrease and improvement at 31.3 %.
Average available pressure is at 15psi but differ in some areas. Generally, treated water is
delivered to the distribution areas by gravity except in some areas with higher elevation.
Present Development. DAWACO is upgrading its water treatment plant at Cau Do using
the same source at Cam Le River. From the current capacity of 70mld, it aims to increase
the production level to a capacity of 120mld scheduled to be operational this year. The
treatment process is conventional.
Report on the Field Visit 10Dec2008 (Final report)
OBSERVATIONS, FINDINGS AND ANALYSIS
We would like to commend the Management Team of DAWACO led by its Director, Engr.
Nguyen Truong Anh, who showed keen interest to Manila
Water’s success story in providing safe and potable water to
its 5 million customers.
Whilst we note that there are areas for improvement on
DAWACO’s water quality management processes, the
managers and key staff of the Cau Do Water Treatment
Plant are adept in the specifics of the facilities. Despite the
language barrier, the WTP Manager was receptive in imparting his knowledge and
experience in the operation of the facilities, His inputs have helped us in coming up with our
preliminary assessment on raw and treated water quality.
Likewise, the team from the Technical Planning Department is very flexible in terms of doing
different functions such as collecting and testing water samples in addition to the planning
works. The team had also shown expertise and knowledge of the distribution system with
respect to pipe sizes, lengths, supply areas, etc which are all necessary to further assess the
quality of water on the distribution side.
DAWACO’s current challenge is on its water quality management, specifically the amount of
residual chlorine of the treated water distributed to its customers which is higher than
standards in some areas near the Water Treatment Plant while lower than standards in some
areas of the distribution system. Both conditions pose hazards to public health. This was
the focus of the 2-day discussions and field visits, to assist DAWACO in addressing its Water
Quality Management
The succeeding paragraphs present our findings and observations during the actual field
visits and water sampling. For a more defined presentation of our report, we have divided
our findings into four (4) areas— Raw Water Source, Treatment, Distribution and Other
Factors all of which, we believe contribute to improving the Water Quality Management
process of DAWACO.
1. Raw Water. The Cau Do Water Treatment Plant abstracts its raw water source from the
nearby Cam Le River through an intake structure and a pond that is directly connected to
a pumping station, where, raw water is conveyed to the WTP located a few meters away.
� The raw water is turbid with a brownish color. We were told
that the turbidity (measured as NTU) varies depending on the
season but the highest so far recorded is 2000 NTU. We note
however, the absence of established daily raw water sampling
and monitoring at the upstream source which will determine in
advance the amount and type of chemicals that will be used
for treatment.
Report on the Field Visit 10Dec2008 (Final report)
� The raw water abstraction point is close to the mouth of the bay, hence, when the
seawater backflows during high tide, the saline water contaminates the fresh water
from the river. This condition which is predominant during dry season may pose
some problems on the water quality since the WTP was designed for fresh water and
not for brackish water, in which case may require more complex treatment, i.e.
reverse osmosis. We suggest however, for a further assessment on the level of
salinity of raw water for a more conclusive study in this aspect.
� There are no established raw water sampling tests for other parameters, i.e chemical,
heavy metals, etc. We believe that for planning purposes, monitoring the quality of
raw water should be in place. This is most needed especially in cases where there is
a marked deterioration of raw water quality and there are activities upstream of the
river, i.e mining, agriculture, industries, etc. Such information will assist DAWACO in
coming up with a plan to address the deterioration of the raw water quality from the
Cam Le River.
2. Water Treatment Plant. The Cau Do WTP and facilities are situated in an area near the
raw water source. The water treatment plant, chlorine house and chemical house are
located a few distances from each other. The WTP uses a conventional treatment
process. Following are our observations at the Cau Do WTP facilities.
� We note that some equipment for testing and analyzing water
quality performances in the laboratory is not sufficient.
Complete set and well-maintained laboratory equipment is ideal
to minimize errors in determining water quality results.
� Absence of analysis for other parameters i.e. heavy metals,
fecal coliforms, etc. Bacteriological Analysis should be done on a
daily basis to measure potability of the supply being distributed Other
water quality parameters for microbiological, biological, physical,
chemical and radiological requirements also need to be checked
at least once a year. Such results are necessary for a complete
water quality evaluation and quick response to water quality
deterioration if there’s any.
� Obtaining the results is manually done. Existing on-line
measurement for residual chlorine may not be reliable. We also
observed the absence of a control equipment and devices for
measuring other necessary parameters like pH and turbidity
� Greenish water is entering the filter beds which, we suspected
to be high in biological counts such as algae. Small and light
flocs were also seen floating in the basins which, may result to
easy clogging of filter beds and thus, more frequent
backwashing. Some leaks were also noted at the filter bed
Report on the Field Visit 10Dec2008 (Final report)
water lines. We believe that efficiency of plant operation, i.e. backwashing and
chemical dosing can still be improved. The quality of the settled and filtered water
maybe enhanced by addition of inter-chlorination.
� Field testing equipment like turbidimeter may need calibration.
Blinking lights seen on the turbidimeter and inconsistency of
results may indicate that the equipment needs to be checked
and calibrated to ensure reliable data.
� We also note that there is no standby generator set in the WTP in case of power
interruptions. The long downtime during outages may contribute to contamination
both at the treatment plant and the distribution lines.
3. Water Supply Network
� As claimed, chlorine residual in the distribution network falls below the necessary
WHO standard to maintain adequate water disinfection for pathogens thus,
endangering customers. Some areas far from the water treatment plant had records
of low to zero residual chlorine. Although the results during our field sampling show a
high residual chlorine, the incidence of low chlorine residual may still recur and may
give a positive coliform test results thus; water is not safe to drink
� The varying supply-demand may also result to unstable levels of residual chlorine
especially at the farthest end of the distribution lines. As
confirmed by the DAWACO Engineer, the chlorine levels are
much lower during non-peak demand while higher when
demand is also high. We find the profile of network system a bit
complex as pointed out in the map with different supply points,
thus, isolation of a problem area maybe quite difficult.
� It was also observed that definite procedures on sample collection and reporting of
results are not in place. During the actual sampling conducted on site, we noted that
the procedures are not complying with the WHO standard. In addition, the water
sample collected should be a representative of the water under examination.
Contamination during collection and before examinations should be avoided.
� Criteria for selection and the frequency of sampling and testing are not yet
established. Data showed that the number of sampling points versus the number of
households is not sufficient based on standards. Generally, selection and frequency
of sampling should take into account the size and complexity of the network lines, the
rate of records yielding unsatisfactory results and the risk of epidemic and the
practice of disinfection.
� Some existing water sampling points --plastic faucet near a
kitchen, a water hose lying on the floor and leaking taps are
not within the standards for collecting points. Taps where
samples are collected should likewise be cleaned, free from
Report on the Field Visit 10Dec2008 (Final report)
attachments and fully opened to allow the water to run for a sufficient time to allow
flushing/cleaning of the service lines.
� The method for testing residual chlorine in the distribution
network can also be upgraded for a more reliable and
accurate results.
� Flushing points and blow offs are not sufficient and not
strategically located to address remedial actions in case of
dirty water complaints.
4. OTHERS FACTORS. The following refer to other items observed and the organization’s
linkages with other agencies to address water quality problems.
� Good housekeeping such as in the laboratory or in critical
areas where the chemicals are stored can still be improved
such as putting signage and provisions for safety.
� Weak approach on responding to reports of dirty water.
CONCLUSIONS/RECOMMENDATIONS
Based on our preliminary findings and observations, following are our recommendations. It
has to be recognized that other observations and analysis presented may not be conclusive
therefore we proposed that this be further assessed during the duration of the program. We
will classify our recommendations into Short-Term, Medium-Term and Long-Term based on
the implementation time-frame and the investment requirement.
1. Short-Term. These are stopgap or interim measures that are crucial, thus, need urgent
attention.
� We propose that Flushing and Disinfection be immediately conducted in the affected
line where the residual chlorine is low. This would entail determining the required
chlorine based on the pipe’s supply volume. Modern methods of flushing and
disinfection can be used to reduce its impact to customers.
� Monitoring of residual chlorine level after flushing and disinfection should continue for
a certain period to assess whether the condition has improved or not.
� The provision of a chlorinator shall be done only if there are indications that the
problem is not eliminated after flushing and disinfection, otherwise, this may not be
needed. The chlorinator is usually installed at the injection point, water tank or
reservoir prior to distribution.
Report on the Field Visit 10Dec2008 (Final report)
� As an alternative and counterchecking of results, we propose to use other method for
determining residual chlorine such as DPD method or use of digital colorimeter to
provide more accurate results.
2. Medium-Term. These are measures or solutions that should be done within 3 months to
one year period
� Cleaning and disinfection of filter beds
� Need to establish policies and SOPs on flushing and disinfection of newly laid pipes,
sample handling, testing, random sampling and sanitary survey based on the WHO
standard.
� Formulate policies and SOPs in cleaning and disinfection of reservoirs, regular
sampling and testing of water reservoirs and pumping stations.
� Establish data for the creation of recommended chemical dosage tables for easy
reference in case of abrupt change in raw water quality. Ideally, the raw water data
should be year-round to capture seasonal changes.
� Set-up procedures on random sampling and sanitary survey to further assess the
source of dirty water quality complaints.
� Set up internal standards and water quality alert levels
� Define criteria for selection of regular sampling points. Through the use of a network
map, the sampling points can be located as a representation of a certain distribution
network.
� Improve sampling collection and handling by training key staff on the proper
procedures
� Purchase monitoring equipment such as turbidimeter, tri-meter, etc. to check color,
pH and turbidity.
� Calibration of field testing equipment to ensure accuracy of results.
3. Long-Term Measures. These are measures or solutions that should be done beyond
the one-year period.
� Acquisition of lab equipment, chemical reagents and sampling paraphernalia
� Process to be in place in analysis, i.e. elimination, isolation, etc
� In case of power outage, there is a need for a continuous supply. Power interruption
may lead to dirty water in the district network. Thus, there is a need for an alternative
Report on the Field Visit 10Dec2008 (Final report)
power supply, for instance, a standby generator set that will automatically switch on in
case of power outage.
� Strengthen linkage and communication with the Ministry of Health, Han Preventive
Center and other government stakeholders, such as the City Government.
� Creation of a Drinking Water Quality Monitoring Committee composed of (i) all other
water utilities including Dawaco (ii) national water laboratories (iii) Local Government
Units (or its equivalent) (iv) representative from the Ministry of Health
� Setting up of internal standards, e.g. KPIs, TMS
� More proactive approach in responding to dirty water quality complaints by setting up
a procedure in such cases.
� Creation of a separate group/department within the Dawaco organization apart from
the Water Supply Department that will be responsible for management, regulation
and research of water quality data of all point sources
Per discussion, DAWACO has agreed to allocate the necessary funding for key
recommendations to manage safe water quality such as purchase of essential equipment,
hardware, materials to maintain adequate chlorine residual in the distribution network.
Next Steps and expected deadlines
� DAWACO has conveyed interest to partner with MWCI. MWCI needs to confirm by
first week of December. Both partners to sign the Letter of Intent to twin by mid-
December.
� With ECO-Asia facilitation, MWCI and DAWACO will develop a joint work plan from
now until September 2009 incorporating the recommended actions noted above
including clear roles, performance indicators, and necessary resources. MWCI will
provide the technical expertise and practical solutions to assist DAWACO, while
DAWACO will provide the required resources to undertake the activities.
� Upon agreeing on the work plan, DAWACO and MWCI will sign a Memorandum of
Understanding to implement the activities in the work plan and mobilize resources
both in funding from DAWACO and in technical assistance from MWCI. Both
partners will sign the MoU by January 2009.
� Preparatory activities will begin in December after LOI signing, which may include
additional assessments of the DAWACO operations by MWCI.
� With ECO-Asia support, both partners will implement the work plan activities until
September 2009.