Challenges of Provision of Sewerage Service in the East Zone of        Metro Manila        R. Baffrey*, J. Mendoza** and A...
water and sanitation sector. In 1997, the existing sewerage facilities were confined to some areas inthe city of Manila an...
ObjectivesThe following are the objectives of this paper:1. To discuss strategies and best practices in establishing an im...
the sewer charge of customers in sewered areas that will amount to almost 50% of their water bill.As a result, Manila Wate...
Figure 2. Sewerage Coverage upon completion of                       CST Upgrade under MSSPFollowing the success of MSSP, ...
Figure 3. Manila Water bagged 12 awards, the most number given                to any company at the 2010 LLDA Public Discl...
900,000                                                  852,848                                                          ...
Figure 7. Olandes Sewage Treatment PlantThe upgrade of CSTs and pilot of combined systems implemented under MSSP and MTSPr...
Government Agencies, d.) Social Acceptability and lastly e.) Operational Challenges.Land AvailabilityLand availability is ...
According to the Concession Agreement, all investment cost for service improvement projects willbe recovered through tarif...
Apart from limited operational expertise, other initial difficulties encountered were limited landallocations, network con...
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Challenges of Provision of Sewerage Service in the East Zone of Metro Manila


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prepared by R. Baffrey*, J. Mendoza** and A. Adis** *Wastewater Operations Department, Manila Water Company, Inc., MWSS-Admin Bldg., Katipunan Road, 1105 Balara, Quezon City, Philippines (E-mail: **UP Sewage Treatment Plant, Arboretum Drive, Quezon City, Philippines (E-mail: **East Ave. Sewage Treatment plant, East Ave., Central, Quezon City, Philippines for Decentralized Wastewater Treatment Systems (DEWATS) for Urban Environments in Asia, 25-28 May 2011, Manila, Philippines. organized by International Water Association (IWA).

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Challenges of Provision of Sewerage Service in the East Zone of Metro Manila

  1. 1. Challenges of Provision of Sewerage Service in the East Zone of Metro Manila R. Baffrey*, J. Mendoza** and A. Adis** *Wastewater Operations Department, Manila Water Company, Inc., MWSS-Admin Bldg., Katipunan Road, 1105 Balara, Quezon City, Philippines (E-mail: **UP Sewage Treatment Plant, Arboretum Drive, Quezon City, Philippines (E-mail: **East Ave. Sewage Treatment plant, East Ave., Central, Quezon City, Philippines (E-mail: Abstract Urban sanitation is one of the most serious challenges facing the Philippines, particularly in Metro Manila. In 1997, Manila Water, a private consortium, obtained the exclusive rights to provide water and wastewater services to the East Zone of Metro Manila. This was through a 25-year Concession Agreement with the Metropolitan Waterworks and Sewerage System (MWSS). Before privatization, sewer coverage in the East Zone was at a low of 3%. This corresponds to the Makati Sewerage System and Communal Septic Tanks (CSTs) in Quezon City, which provide secondary and primary treatment respectively. Likewise, capacity for sanitation services was inadequate. Only one desludging truck was available with no facility for appropriate septage disposal and treatment. Fourteen years since the start of the concession, Manila Water now operates 38 treatment facilities and over 78 desludging trucks to provide sewerage and sanitation services in the East Zone. These treatment facilities have a total capacity to treat 135 million liters of wastewater per day. Included in these facilities are 2 septage treatment plants that have served 852,848 households. Manila Water has achieved these through the following integrated strategies a.) Upgrade of Communal Septic Tanks, b.) Septage Management and c.) Pilot-testing of Combined Systems. These strategies, which include technical and non-technical components, allowed Manila Water to provide a solution to the growing problem of domestic pollution discharge to major river systems. More importantly, this paper aims to discuss the challenges encountered by Manila Water all throughout project planning and implementation, citing specific examples and lessons learned. These challenges include land availability, stakeholder endorsement, cooperation with government agencies, social acceptability and operational challenges. Keywords Sewerage, Sanitation, Manila Water Company, East ZoneINTRODUCTIONBackgroundPopulation influx and unregulated industrial development promoted rapid environmentaldegradation in Metro Manila. Major water bodies such as the Marikina, San Juan, and Pasig Riversare biologically dead from indiscriminate discharge of untreated wastewater. The Manila Bay andLaguna Lake are also in serious worsening condition.The amount of biochemical oxygen demand (BOD) discharged to the water environment of MetroManila has been estimated by World Bank to be 330,000 tons per year. Domestic waste generatedaccounts for 58% of this BOD loading, and the remaining 42% was from industries. This conditionof urban sanitation in Metro Manila is reflective of the lack of prioritization of investment in the
  2. 2. water and sanitation sector. In 1997, the existing sewerage facilities were confined to some areas inthe city of Manila and parts of Makati only. Most households utilize their own septic tanks orcommunal septic tanks (CSTs) while those who live in slum areas rely on rudimentary latrines,some even without proper toilet facilities.The Metropolitan Waterworks and Sewerage System (MWSS) is the agency with a direct mandateon sewerage and sanitation. Its concession agreements with Manila Water Company, Inc. (ManilaWater) and Maynilad Water Services, Inc. include specific commitments on the provision andexpansion of sewerage and sanitation services in Metro Manila. Sewerage refers to a pipe collectionnetwork for sewage and the treatment of the collected sewage in a sewage treatment plant (STP).Sanitation, on the other hand, refers to the emptying of domestic septic tanks and subsequentseptage/sludge treatment and disposal.In response to government calls for the acceleration of the provision of sewerage services, ManilaWater, the concessionaire for the East Zone of the MWSS service area, has intensified its efforts byembarking on major sewerage and sanitation projects. Instead of proceeding with the conventionalapproach of centralized sewerage systems, Manila Water employed a different strategy. Theconcessionaire adopted an innovative approach, a master plan that first focused on a phased processof converting the common technology of CSTs into community-based, decentralized treatmentplants before eventually focusing on larger combined sewer-drainage systems. Major upgrades onthe community-based treatment plants have been completed. For the rest of its coverage area,Manila Water embarked on modernizing its fleet of desludging trucks and enhancing septagetreatment capacity to maintain efficiency of septic tanks in areas that have yet to be connected tosewer networks. Manila Water’s proactive approach to the challenge of providing sewerage andsanitation services was effective as it resulted in significant increase in the number of beneficiariesserved.RationaleWastewater management presents even greater challenges compared to supplying clean, safe tapwater. Due to space constraints and the sheer cost of the wastewater infrastructure required,accelerated implementation of centralized sewer networks in Metro Manila is a near impossibletask.Innovative and unconventional solutions were needed to address the sewerage and sanitation needsof Manila Waters concession area. Some methods of tackling the issue included transforming CSTsinto compact or decentralized STPs. The CSTs were outfitted with equipment for primary andsecondary treatment to treat in-coming wastewater before releasing it to rivers and streams. ManilaWater has successfully implemented this decentralized approach through the World Bank-fundedManila Second Sewerage Project (MSSP) and constructed 26 new package STPs between 2002 and2005. This focus on transforming CSTs into decentralized treatment plants was primarily due toManila Water’s decision to identify projects anticipated to deliver the most immediate impact andtangible results in the provision of sewerage services in the East Zone. Through this, Manila Waterdoubled its sewage treatment capacity, and benefitted more than half a million people by 2005.Moreover, the company increased removal efficiency of existing septic tanks through provision ofregular desludging, septage treatment and disposal.Through an on-going follow up project called the Manila Third Sewerage Project (MTSP),upgrading of existing CSTs to STPs was continued. However, to further accelerate expansion ofsewerage services, this approach was implemented with the new combined sewer-drainage system.The conceptualization of the MTSP components took into account the limitations and lessonslearned from implementing past projects under the MSSP. Understanding the considerations of thestrategies presented above will be critical in providing examples of successful project applicationand lessons learned in implementation. These will serve as bases for establishing sound solutionapproaches to the growing problem of domestic pollution and assist in the development of a morecomprehensive forward-looking wastewater management plan.
  3. 3. ObjectivesThe following are the objectives of this paper:1. To discuss strategies and best practices in establishing an immediate improvement of sewerageand sanitation services in the East Zone of Metro Manila;2. To discuss key issues which limit the efficient implementation of sewerage and sanitationprojects;3. To present how past project experience led to the development of a long-term sewerageexpansion plans and programs in the East Zone that are intended to address the increasing pollutiondischarge to Metro Manila’s river systems.MANILA WATER’S STRATEGY1997 SituationAt the start of Manila Water’s concession in 1997, there were only two sewage treatment facilities.This included the Makati South STP, with a capacity of 40 million liters per day (MLD) serving theMakati Central Business District and surrounding residential communities. The second treatmentfacility is the package treatment plant located in Karangalan Village in Pasig City, which had acapacity of only 0.1 MLD. In addition, there were a total of 34 CSTs in Quezon City providingonly primary treatment to 17,000 households. It is worthwhile to note that all facilities were invarious states of disrepair and required significant infrastructure improvements for upgrade tointernational standards. These facilities served a total of only 40,000 households which is only 3%of the total East Zone population. Aside from this minimal sewerage service, the sanitation wasinadequate as well. There was only 1 vacuum tanker transferred to Manila Water and no facility wasavailable for appropriate disposal and treatment of septage. Figure 1. Sewerage Coverage in MWSS Area before 1997 (*Note: Items 3 and 4 are the old sewerage systems located in the East Zone, which was turned over to Manila Water upon privatization)AccomplishmentsBased on previous sewerage master plans of MWSS, the initial technical solution for Manila Waterto meet the original sewerage target was to put up centralized sewerage systems. But due to timeconstraints and the magnitude of the work needed, Manila Water deemed it to be unworkable forthe East Zone in the short term. The construction required would have included massive roadexcavations and a land area of 47 hectares, both of which were clearly not feasible at that time. Inaddition to this, there was the issue of customers’ unwillingness to pay an additional PhP 10/cubicmeter increase in water tariffs to recover the extremely high capital investment cost. This excludes
  4. 4. the sewer charge of customers in sewered areas that will amount to almost 50% of their water bill.As a result, Manila Water put forward a strategy that was both technically feasible and affordable tocustomers. Initially, this strategy was anchored upon decentralized sewerage systems and a massivesanitation service program. By upgrading first existing CSTs to STPs, population coverage wasmaximized at an efficient cost and with minimal disruption. In addition to this, an extensivesanitation program relying on the provision of regular septic tank maintenance or desludging wasimplemented to cater to non-sewered areas. To further expand sewer service coverage, ManilaWater is now piloting combined sewer-drainage systems.Upgrade of CSTs. At the onset, the CSTs turned over to Manila Water did not operate efficiently,desludging was infrequent and in some cases the tank access manholes were covered and built overwith housing structures. The operation and maintenance of the CST’s was hampered further byaccessibility problems due to ownership issues. This led to the takeover and proliferation ofinformal settlers and/or claimants to the land occupied by these facilities.The presence of the informal settlers on the CST sites posed a serious threat to the health of theseresidents. Moreover, without regular desludging, these facilities were rendered useless in theprimary treatment of sewage. Eventually, when the sludge accumulation reached the maximumlevel, wastewater enters and leaves the CST with no treatment at all, thus polluting the waterwaysreceiving the effluent.The immediate need to address these issues was also one of the key considerations in the upgrade ofCSTs. Implementation of this initiative was made possible in resolving the ownership issuesamongst the National Housing Authority (NHA), local government units (LGUs), MWSS andManila Water.Project Development and Implementation. The MSSP was a World Bank loan amounting to $36.1M provided in 1996 to MWSS. A key component of the MSSP focused on the rehabilitation andupgrade of existing sewerage systems including the Makati South STP and strengthening of thecapacity for sewer maintenance. Crucial changes in the MSSP Loan Agreement paved the way forthe inclusion of the MSSP Community Sanitation Projects, a component dedicated to the upgrade ofCSTs into localized and decentralized STPs. Existing communal septic tanks were advantageousbecause they allowed for the utilization of pre-existing MWSS assets and minimal sewer pipelaying.By early 2002, Manila Water conducted consultations with several densely populated communitieshaving CSTs. The consultations were held to assess public interest of the different communities onhaving package treatment plants. Subsequently, by the end of 2005, 28 STPs were operational.Manila Water’s sewage treatment capacity then grew from 40 MLD to 80 MLD. In addition, sewercoverage also rose to 10% in 2005 compared to the 3% in 1997.
  5. 5. Figure 2. Sewerage Coverage upon completion of CST Upgrade under MSSPFollowing the success of MSSP, Manila Water implemented the MTSP in 2005 aided by a $64 Mloan from World Bank. Through the MTSP, Manila Water embarked on larger systems using thesame decentralized approach. Some existing CSTs were converted to sewage pumping stations thattransported collected sewage to a centrally-located CST which, in turn, was transformed into amini-regional STP. Such an example is the East Avenue STP located near the National EcologyCenter, which treats flows discharging to the old Rimas, Anonas, Mapagmahal and East AvenueCSTs.By 2011, there are already a total of 38 treatment facilities including two septage treatment plants(SpTPs), totalling to a treatment capacity of 135 MLDOperations Performance. Most of the CSTs turned over by MWSS are now operating activatedsludge STPs. For the compliance performance assessment of these facilities, external monitoring isdone by the Department of Environment and Natural Resources (DENR) and its sub-agency,Laguna Lake Development Authority (LLDA), while a more stringent internal monitoring system isalso in place.Despite some initial operational challenges, Manila Water’s wastewater facilities remainedcompliant with DENR/LLDA standards for wastewater effluent. Similarly, regulatory requirementsof the MWSS Regulatory Office in terms of wastewater treatment have also been consistentlycomplied with. Manila Water also initiated an Integrated Management System consistent withOHSAS 18001 and ISO 14001 for pilot STPs to demonstrate its drive for environmental, health andsafety excellence.
  6. 6. Figure 3. Manila Water bagged 12 awards, the most number given to any company at the 2010 LLDA Public Disclosure Program and Awarding Ceremonies of Industries’ Environmental PerformanceThese efforts to improve and expand wastewater services in the East Zone of Metro Manila arealigned with the Philippine Clean Water Act’s (CWA) objectives of protecting our water resourcesfrom further degradation. In fact, in 2010, the Company effectively removed 2,735 tons of BOD,which would have otherwise added to the pollution of Metro Manila’s water bodies.Septage Management. Aside from the sewerage strategy, there is also the sanitation program. Thissanitation program revolves around the concept of septage management. Septic tanks provideprimary treatment by reducing the solid content of the discharge. Though primary treatment is done,the effluent is still not in compliance with DENR standards. This primary treatment capability ofseptic tanks is further reduced if regular maintenance is not performed. Thus, Manila Water deviseda strategy to maintain household septic tanks through septage management. This service is mainlycatered to households that are not connected to a sewage treatment plant.Septage management is accomplished through the desludging of septic tanks by vacuum tankersevery 5-7 years. This desludging program is carried out in coordination with barangays to facilitateefficient service to Manila Water customers (Sustainability Report 2008). Figure 4. Septic Tank Emptying and Septage ManagementPresently, there are over 78 Manila Water desludging trucks compared to the inherited 1 vacuumtanker in 1997. These desludging tankers transport household septage to the 2 septage treatmentfacilities, FTI and San Mateo SpTPs. Both facilities were completed in 2007 through the MTSP.These two facilities are the biggest in the region in terms of treatment capacity having treatedseptage from a massive 852,848 households in the East Zone of Metro Manila.
  7. 7. 900,000 852,848 826,870 800,000 700,000 Number of Households 600,000 584,844 500,000 400,000 300,000 293,375 200,000 105,109 100,000 0 2007 2008 2009 2010 2011 Year Figure 5. Cumulative number of households desludgedPilot-testing of Combined Systems. Currently, under the MSTP, Manila Water is implementing athird strategy in sewage management and this is the Combined Sewer-Drainage System. Thissystem will capture the wastewater coming from existing drainage systems, thereby minimizing thelaying of large sewer pipes (Sustainability Report 2008). Figure 6. Combined Sewer-Drainage SystemIn 2009, 2 pilot combined sewer-drainage treatment plants were completed: Pineda STP andOlandes STP, having capacities of 4 MLD and 10 MLD, respectively. Lessons learned from thedevelopment of these two systems will be utilized to refine and optimize future implementation ofcombined sewer-drainage systems. As pilot systems, both facilities experienced early operationalissues. Design modification and innovations arrested these issues. In fact, Olandes STP receivedglobal recognition from the International Water Association’s 2010 Asia Pacific Regional ProjectInnovation Award with an Honor Award for Small Projects because of its state-of-the-art design.Since Olandes STP is located in a flood-prone area, the STP was designed accordingly.
  8. 8. Figure 7. Olandes Sewage Treatment PlantThe upgrade of CSTs and pilot of combined systems implemented under MSSP and MTSPrespectively are only initial steps towards the company’s long term goal of more widespread sewercoverage. Manila Water plans to embark on covering 100% of the expansive catchment areas of theMarikina, San Juan and Pasig Rivers using combined sewer-drainage systems. In coordinationwith MWSS, the company is working on the approval of this master plan. Through this approach,Manila Water intends to achieve a successful river rehabilitation model that can be emulated inother similar regions (Sustainability Report, 2007).Ultimately, the entire service area is still planned to have 100% sewer coverage in terms of actualconnection to sewer systems. Given the fact that separate conventional sewer systems is still thebest sustainable solution in terms of wastewater management, Manila Water will work towards thephased installation of sewer lines and eventual conversion of combined sewer-drainage systems intoseparate systems.Figure 8. Sewerage Expansion Plan for the East ZoneCHALLENGESIn the fourteen years since the start of the Concession Agreement, Manila Water’s provision ofsewerage and sanitation services in the East Zone encountered numerous challenges, summarizedinto 5 major categories: a.) Land Availability, b.) Stakeholder Endorsement, c.) Cooperation with
  9. 9. Government Agencies, d.) Social Acceptability and lastly e.) Operational Challenges.Land AvailabilityLand availability is one of the major challenges in building treatment facilities. Treatment plantsand lift stations require large areas of land. Unfortunately, Metro Manila is the most populatedmetropolis in the country. Large available open spaces are scarce, and what minimal available landis typically inhabited by informal settlers. Also, identified sites are typically unavailable due toprioritization of residential and commercial developments.Depending upon the exact location, the cost for land could take up a large percentage of the totalproject cost. Land acquisition henceforth is difficult due to both the access to large available landand the financial implications of purchasing the identified land.Consequently, the ideal model is to acquire land through donation from government units andagencies. Consistent with this approach, the Clean Water Act states that local government units aremandated to allocate land for wastewater facilities. In this regard, the assistance of the nationalgovernment and local government agencies is a critical factor in acquiring land. Usufructagreements were successful in gaining new land for current projects; hence, are a continuingstrategy being pursued to acquire adequate land for future projects as well.Stakeholder EndorsementEndorsement from respective communities and local government units (LGUs) is a key factor ineither the success or failure of a project. Public consultations were conducted during the projectdevelopment wherein all involved parties were invited, especially the residents of the community.When endorsement is obtained from these stakeholders, procuring permits and right-of-way grantsfor the treatment facility’s construction and operations is made more efficient. Subsequently, therisk of delays due to resident complaints can be minimized.Alternatively, without proper endorsement, project implementation deadlines may not be met. Otherrisks include frequent changes in local government administration, miscommunication betweenstakeholders regarding project objectives and the general negative perception of wastewaterfacilities.Cooperation with Government AgenciesAnother challenge encountered is the cooperation of different agencies. In the Clean Water Act,there are 3 national agencies that are mandated to have direct involvement in sewer managementand these are: a.) DENR, b.) Department of Health (DOH) and c.) Department of Public Works andHighways (DPWH). With the use of the Combined Sewer-Drainage Systems, close coordinationwith LGUs, DPWH and the Metro Manila Development Authority (MMDA) is vital.Solid waste easily clogs sewer networks and drainage systems. Subsequently, solid waste alsoaccumulates quickly in STPs and poses operational concerns. Since LGUs have the greatest impacton solid waste management, close coordination with these entities, combined with public awarenesscampaigns on proper waste disposal, need to be accomplished.Aside from LGUs, other agencies closely coordinated with include NHA, Bases ConversionDevelopment Authority (BCDA), Housing and Urban Development Coordinating Council(HUDCC) and the Home Guaranty Corporation (HGC). The housing agencies’ capability to allotland for future partnerships is vital for existing and future projects on wastewater services to pushthrough. For instance, 9 package treatment plants located in Karangalan Village in Cainta, Rizal andPasig City were completed through the partnership with NHA. Memoranda of Agreement (MOA)with NHA were executed for easements on the parcels of land owned by the said agency to installthe decentralized STPs. These treatment plants were commissioned and have been operationalsince 2005.Social Acceptability
  10. 10. According to the Concession Agreement, all investment cost for service improvement projects willbe recovered through tariff using rate rebasing exercises. The tariff is composed of the basic watertariff with an additional sewer charge for customers in sewered areas. The issue on socialacceptability arises from the unwillingness of customers to pay for additional fees for bettersewerage and sanitation service. This stems from an apparent lack of awareness regarding thebenefits of these services to human health and the environment.In relation to this, affordability studies indicate that average incremental cost for sewerage is toohigh compared to what the customers are willing to pay. Therefore, in order to provide theseservices a comprehensive tariff structure needs to be applied that combines potable water deliverywith adequate wastewater treatment and disposal. This is justified by the end benefits of the project,which is shared by all and not just the community served by the treatment facility. This approachallows more expedient project implementation to address the pollution of the rivers.In addition to appropriate tariff setting, initiatives must be applied to further educate customers onthe need for sewerage and sanitation services. For instance, Manila Water has institutionalized aWater Trail Program referred to as “LAKBAYAN” where students, guests and representatives fromLGUs and non-government organizations partake in an information awareness campaign on thetreatment of water and wastewater. In 2010, Manila Water conducted Lakbayan tours and plantvisits were 3000 stakeholders participated.Operational ChallengesDue to the limited number of facilities and infrastructure at the onset of wastewater operations in1997, there was consequently a lack of personnel with extensive experience in wastewatermanagement. To address this need, Manila Water employed a cross-functional training program toassimilate international practices and enhance institutional expertise.On-site operational personnel were given the tools and training to become the ultimate custodians oftheir assigned facilities. These personnel with no previous background on sewerage services andlimited technical knowledge have developed into capable wastewater treatment plant operators.Among the skills developed are basic wastewater characterization and analysis, processtroubleshooting and the implementation of innovative techniques to increase operational efficiency.Several of these personnel have been consistently nominated and at several instances won theHuwarang Manggagawa (Model Employee) Award, the highest recognition given to a staff-levelemployee of Manila Water. This strategy has been a cornerstone of Manila Water’s wastewateroperations. Figure 9. Winners of Huwarang Manggagawa (Model Employee) Award: Alberto Ramirez (4th from L to R) and Ernesto Labanza (5th from L to R) are operators from the Wastewater Department
  11. 11. Apart from limited operational expertise, other initial difficulties encountered were limited landallocations, network control, utilization of STPs, rigidity of operation and monitoring. Thesedifficulties were addressed via succinct risk-based planning. Testing and commissioning strategieswere continually improved and all parties were immersed throughout project planning anddevelopment.CONCLUSIONSince 1997, Manila Water has exerted efforts in providing wastewater services in the East Zone ofMetro Manila. All these were accomplished through three main strategies, namely: upgradingCSTs, septage management and combined sewer-drainage systems. All three strategies wereselected based on maximizing immediate benefits to customers in the most cost-effective andfeasible manner.Throughout project development, major factors have been identified as inhibiting theimplementation of sewerage and sanitation projects. These include a.) land availability, b.)stakeholder endorsement, c.) cooperation with government agencies, d.) social acceptability and e.)operational challenges. Challenges were addressed by an integrated approach considering propercoordination with concerned parties and appropriate consideration of customer needs.Given the past challenges experienced by Manila Water, it is apparent that the successful provisionof sewerage services can only be accomplished with the full support of government organizationsand the general public. This integrated approach will undoubtedly guarantee a rapid solution tosustaining our rivers for future generations.REFERENCESManila Water Company Inc. “Sustaining Generations”. 2009 Sustainability Report.Manila Water Company Inc. 2008 Sustainability Report.Manila Water Company Inc. 2007 Sustainability Report.Manila Water Company Inc. Rate Rebasing Report, 2007.Manila Water Company Inc. Feasibility Study for the Manila Third Sewerage Project. Final Reportby Nippon Jogesuido Sekkei Co., Ltd in association with CEST, INC. and Mott MacDonald Co.,Ltd, 2004.Manila Water Company Inc. Regional Environmental Assessment for Manila Third SewerageProject.Manila Water Company Inc. Master Plan Final Report. December, 2004.Manila Water Company Inc. website. "Manila Water Company: Investor Guide".