prepared R. Baffrey*, M. Adriano** *Wastewater Operations Department, Manila Water Company, Inc., MWSS-Admin Bldg., Katipunan Road, 1105 Balara, Quezon City, Philippines (E-mail: robert.baffrey@manilawater.com) **South Septage Treatment Plant. Manila Water Company, Inc., Rambutan cor Langka Rd., FTI Complex, Taguig City, Philippines (E-mail: mel.adriano@manilawater.com) for Urban Environments in Asia, 25-28 May 2011, Manila, Philippines. organized by International Water Association (IWA).

1. “Sanitasyon Para Sa Barangay”:
Manila Water’s Experience in Septage Management
R. Baffrey*, M. Adriano**
*Wastewater Operations Department, Manila Water Company, Inc., MWSS-Admin Bldg., Katipunan Road, 1105
Balara, Quezon City, Philippines
(E-mail: robert.baffrey@manilawater.com)
**South Septage Treatment Plant. Manila Water Company, Inc., Rambutan cor Langka Rd., FTI Complex, Taguig
City, Philippines
(E-mail: mel.adriano@manilawater.com)
Abstract
Aside from providing clean and potable water to more than six million customers in the Metro
Manila East Concession, the Manila Water Company also endeavors to protect human health and
the environment through the effective implementation of sewerage and sanitation services. The
provision of effective sanitation services is a key developmental challenge in the Philippines
especially in light of the country’s rapid urbanization and population growth.
In 2004, the Philippine Government enacted Republic Act (RA) No. 9275, otherwise known as
Philippine Clean Water Act. Under the Act, water utilities in highly urbanized areas, in
coordination with local government units (LGUs), are required to connect customers to existing
sewer lines, subject to the payment of sewerage fees. In areas where there are no sewer lines, water
utilities may adopt a sanitation improvement program that will regularly remove septage (the
combination of sewage, scum and sludge) that accumulates in septic tanks to maintain treatment
efficiency.
Manila Water Company, as part of its concession agreement with the Metropolitan Waterworks
and Sewerage System (MWSS), has been very aggressive in meeting its sewerage and sanitation
service targets. Currently, Manila Water employs a fleet of 78 vacuum tankers to meet the demand
for desludging services. In addition to this, Manila Water constructed two septage treatment plants
with a combined capacity of approximately 1,400 m3/day. To date, a total of 850,000 households
have already benefited from this sanitation service. Apart from improvements in sanitation, Manila
Water also increased sewage treatment capacity by converting communal septic tanks to package
treatment plants, constructing combined sewer-drainage systems and expanding sewer network
coverage by 20%. Experience reveals that provision of sanitation services is a cost effective
solution to pollution abatement when integrated with innovative approaches and an enabling
regulatory environment.
Keywords
Septage, sanitation, sludge, biosolids, Manila Water Company
INTRODUCTION
Background
Domestic wastewater or sewage comes from the sinks and toilets of homes, and contains dissolved
and solid material composed of organic matter, oils, grease, surfactants, and garbage. In Metro
Manila, the most common household-level intervention utilized for addressing this waste is the
construction of individual septic tanks (ISTs). Considered to perform “primary treatment”, septic
tanks treat waste via the retention of wastewater for a sufficient period of time to allow for most of
the polluted components to settle. The treated wastewater from the surface of the ISTs, which still
contains trace contaminants, is then allowed to overflow or discharge to either communal drainage
systems or directly to surface water bodies.
The material that settles at the bottom of the tanks is defined as “septage” and materials like silt,
grit, plastic, rags, scum and organic matter are defined as “sludge”. Over time, a sufficient amount

2. of sludge accumulates and needs to be removed or “desludged” so as to maintain the treatment
efficiency of the IST. This material is more concentrated than domestic wastewater and is highly
malodorous due to the presence of hydrogen sulphide and volatile fatty acids produced by the
degradation of the septage in the septic tank. If not removed at appropriate intervals, the material
does not only cause nuisance issues for the household, but also becomes a threat to human health
due to potential exposure to pathogens.
At the onset of the concession between the Metroplitan Waterworks and Sewarage System (MWSS)
and Manila Water in 1997, it was estimated that 85% of the population were utilizing septic tanks
(Manila Third Sewerage Project, 2004). Owing to the fact that a large percentage of these were
improperly designed, constructed, and maintained, it was estimated that up to 58% of the organic
load to Metro Manila’s receiving bodies of water were from these household sources (Manila Third
Sewerage Project, 2004). Organic load is typically quantified by Biochemical Oxygen Demand
(BOD), which is an indirect measure of the amount of oxygen consumed by pollutants that in turn
effectively reduce the available oxygen required to sustain aquatic life. In 2006, the Department of
Environment and Natural Resources (DENR) estimated that the service industry and household
sectors were the major contributors of BOD to the region’s surface water. (Regional Environmental
Assessment for Manila Third Sewerage Project, REA, 2006).
Due to the organic load received from these sources, Metro Manila’s three main water bodies, the
Pasig, San Juan, and Marikina Rivers, are all in various states of biological degradation, ultimately
contributing to poor water quality in Laguna Lake and Manila Bay. Although an ulitmate plan for
sewerage management is aggressively being pursued by Manila Water, it is clear that septage
management is, and will continue to be, an essential component in addressing pollution from
domestic sources.
Figure 1. Biologically dead waterway
Rationale
Before the privatization of the Metropolitan Waterworks and Sewerage System (MWSS) in 1997,
sewerage facilities were confined only to isolated areas in the city of Manila and parts of Makati
City, accounting for only 3% coverage. These sewerage facilities were comprised of minimal piped
networks used to collect and transport sewarage from homes to treatment facilties before discharge
to receiving water bodies. The apparent lack of prioritization for sewerage and sanitation was due
to huge financial requirements and the urgency of expanding and increasing reliability of the water
distribution system (Inocencio, 2001).
As discussed previously, the major reason for providing adequate treatment and disposal systems
for septage is to protect public health and the environment, as septage may harbor disease-causing
viruses, bacteria, and parasites (EPA, 1994). Poor maintenance of septic tanks may cause overflows
which may spread water-borne diseases through infiltration into water pipes in instances of negative

3. pressure, subsequently increasing the probability of human contact. Aside from the health impacts,
the discharge of untreated domestic waste from septic tanks to receiving water bodies also has a
social and economic impact, as previous use of these water bodies for tourism, livelihood, and
recreation becomes severely hampered.
The need for septage management is reflected in various national laws including Philippine
Republic Act 9275 or the Clean Water Act. Under the Act, water utilities in highly urbanized areas,
in coordination with local government units (LGUs), are required to connect customers to existing
sewer lines subject to the payment of sewerage fees. In areas where there are no sewer lines, water
utilities may adopt a sanitation improvement program that will regularly remove septage (the
combination of sewage, scum and sludge) that accumulates in septic tanks to maintain treatment
efficiency.
In line with national laws and to address this deficit in sewerage and sanitation, Manila Water
aggressively pursued sewerage projects through the Manila Second Sewerage Project (MSSP) and
Manila Third Sewerage Project (MTSP), resulting in an increase of sewerage coverage (piped
systems) from 3 to 23 percent.
Figure 2. Sewerage Expansion Plan for the East Zone
Treatment facilities were also expanded in the East Zone from two treatment plants in 1997, to 38
treatment plans in 2011. Currently, Manila Water has a treatment capacity of 135 million liters of
wastewater per day and a corresponding sewer network of over 300 kilometers. To address those
areas not currently connected to piped sewer networks, Manila Water employs a comprehensive
septage management plan to arrest pollution from household sources.
The MTSP, which is composed of institutional strengthening, sewage management, and the septage
management, has allowed for numerous improvements of the provision of service to customers of
the East Zone. Under the septage management component, a fleet of desludging tankers were
purchased and two major septage treatment plants were constructed to completely address the need
for septage services for the duration of the concession. Both facilities are currently operational and
have served a combined total of 850,000 households in the East Zone.
Objectives
This paper will discuss Manila Water’s experience in the effective implementation of septage
management in the East Zone of Metro Manila, focusing on key elements of success as well as
operational challenges.

4. SERVICE AREA AND OBLIGATIONS
Service Area
Manila Water services the Eastern portion of Metro Manila and the province of Rizal, spanning a
total area of 1,400 square kilometers and covering 23 cities and municipalities. Manila Water
currently provides water and wastewater services to more than 6 million people in the East
Concession area, 1.6 million of which belong to low-income communities.
To provide comprehensive service, Manila Water adopted a decentralized structure that subdivided
the East Zone into eight business areas comprised of Balara, Cubao, Pasig, Mandaluyong, Makati,
Taguig, Marikina, and Rizal/Antipolo. This structure enables the company to have increased
accountability and contact with customers, allowing greater opportunity to identify and immediately
respond to customer needs and concerns.
Marikina
Balara
Balara Antipolo
Cubao
Cubao
The
San Juan/
Mandaluyong
Eight
Business Areas
Mandaluyong
Makati
Makati
Pasig
/
Taguig
Figure 3. Location of the Eight Business Areas of Manila Water
8.8 % Domestic Customers
(including low-income
0.4 % communities)
Semi-business and
Commercial Accounts
90.8 %
Industrial Customers
Figure 4. Allocation of Service Connection in terms of Rate Codes
This structure also allows for better “on the ground” coordination with customers and local
government units, resulting in shared ownership of water and wastewater service provision. This
has been a key strategy in the successful implementation of non-revenue water (NRW) reduction as
well as septage management. This has been particularly beneficial for septage management, where
limited awareness and acceptance of this service has been prohibitive in past implementation.
Drilling down operations to the smallest unit, Manila Water employs innovative methods to have

5. frequent and direct contact with customers. These initiatives ultimately become the most effective
means of educating customers on the value and need for the septage services provided, and also
allow for operational efficiencies that result in more rapid delivery of service and prudent resource
management.
Accomplishments to Date
To address septage service obligations in an already massive yet continually growing concession,
Manila Water financed the design and construction of the North and South Septage Treatment
Plants (SpTPs). The North SpTP has a capacity of 586 m3/day and is located in Barangay Gitnang
Bayan II San Mateo Rizal, servicing the areas of San Mateo, Quezon City, Marikina, and San Juan.
The South SpTP has a capacity of 814 m3/day and is located in the Industrial Area of the Food
Terminal Inc. in Taguig, servicing the areas of Mandaluyong, Pasig, Makati and Taguig. These two
plants have a combined treatment capacity of 1,400 m3/day and employ state of the art process and
equipment capable of treating a wide range of septage characterstics to consistenly meet the Class C
standards specified by DENR.
For the collection and transport component, the company invested in the procurement of a fleet of
vacuum trucks and accessories that allow for desludging operations in confined, over-populated
areas.
Among the substantial environmental and health benefits estimated from these sanitation services
are the following:
1. Reduction in the frequency of overflowing septic tanks;
2. Reduction of the health risk from contact with septage in drainage systems; and
3. Elimination of the indiscriminate dumping of raw septage by private contractors.
SEPTAGE MANAGEMENT PROGRAM
Septage management services are comprised of the following:
1. “Desludging” or the collection of septage from individual septic tanks,
2. “Hauling” or transport of the collected septage to treatment plants, and
3. Treatment of the septage to appropriate discharge standards.
Details, operational challenges, and innovations for the above are discussed in the following
sections.
Collection and Transport
Desluding services are performed periodically per household every five to seven years depending
on the volume of the individual septic tank. The service is provided free of charge for the first
desludging activity, and may be availed of again by the customer within the next 5-7 years at a
minimal cost.
“Sanitasyon Para Sa Barangay” (Sanitation for the Community). To aid in this effort, Manila
Water implements a scheduled desludging program known as “Sanitasyon Para Sa Barangay”. This
is a vital counterpart of the company’s “Tubig Para Sa Barangay” (Water for the Community)
program that corresponds to water service delivery targeted at low-income areas of the East Zone.
The per barangay innovation is key to the program’s success since it provides a more targeted and
personal provision of service, allowing for the enhanced participation of local government units as
well as a venue to increase awareness on the value of wastewater treatment in protecting health and
the environment. By an integrated effort through the local government unit, households become
aware of the service and oftentimes prepare in advance for service delivery.

6. Figure 5. Desludging Service to a Manila Water Customer
Issues such as customer unwillingness to avail of the service as well as logistical considerations,
which includes limited access to septic tanks, are typically mitigated via the “Sanitasyon Para Sa
Barangay” approach. Without proper understanding and valuation of this service, certain customers
have the tendency to be uncooperative when offered the desludging service. Apart from the obvious
impact this has on the health and environment, this also reduces the efficiency of collection since
the number of households served during transport of a single vacuum truck needs to be spread over
a greater area of customers. In addition to this, the time spent in attempting to convince residents on
the spot, contrasted against advanced notification, also reduces operational efficiency. Notification
and promotion through the local government addresses this concern by highlighting its community-
wide impact and packaging the service as something that is essential and that shouldn’t be missed
out on.
Local and national level policy formulation and enforcement is also vital to this effort. It is pertinent
that residents be aware that wastewater treatment is not an option but a requirement for the
continued protection of the environment. Manila Water continues to collaborate with local
governments on the evaluation of potential sanitation ordinances aimed at the protection of resident
health and local water bodies. A primary consideration in the delivery of this service is the
minimization of inconvenience and cost-impact to residents.
Operational Considerations. Manila Water utilizes 78 vacuum tankers to deliver septage services.
These trucks have various capacities to allow for more optimization of collection operations,
quantities and sizes are as follows: 51 units of 10m3, 19 units of 5m3 and 8 units of 1.5m3.
Typically, larger capacity trucks are utilized for areas with wide roads and ease of access to septic
tanks, while smaller capacity vehicles cater to those areas with difficult or narrow access.
Manila Water continually provides services in the most efficient and effective manner so as to
reduce impact to its customers. As such, in septage collection and transport it is vital that the
optimum allocation of resources be planned and allotted effectively. Since a massive septage
management program of this nature is the first in the Philippines, it was essential that all lessons
learned and information acquired be collected, organized, recorded, and evaluated in a manner to
assist in the optimization of operations moving forward. A robust database has been assembled that
allows for detailed information on per household level to be extracted prior to the scheduled
desludging service. The size and number of trucks, collection routes, time of collection and
customer coordination are all considered in detail so as to maximize the benefit of the desludging
program.
This planning, combined with the appropriate community coordination, allows for the correct type

7. of truck and mapping of routes, as well as advanced preparation against operational issues such as
space constraints. Ideally, the desludging customer can make adequate preparations such as
providing adequate access to septic tanks prior to the activity.
Continuous technical improvement and innovation is also provided to further augment operational
efficiency. Due to the extensive areas to be served by septage management, a significant workforce
is required to deliver this service. As such, Manila Water employs an integrated approach to talent
management that maximizes internal and external manpower to deliver on service obligations.
While technical expertise and management continues to be developed and housed internally, the
labor-intensive portion of collection and treatment operations may be outsourced to provide
opportunities for employment in the East Zone.
Equipment innovations are also being pursued in order to increase the flexibility of the current fleet
of vacuum tankers. Collection mechanisms that allow more targeted collection of only the most
polluted portion of septic tanks is a key initiative that can greatly increase the effectiveness and
efficiency of collection. In addition to this, optimum collection routes and integrated facility
utilization are also being evaluated to improved service delivery. Manila Water employs a targeted
research and development program that aims to drive down operational costs via efficient
technology to lower fuel and power consumption.
These technical and community-based innovations have allowed Manila Water to exceed
desludging targets in its concession area. As of February 2011, 217,765 septic tanks were
desludged, benefiting 850,000 households in the East Zone of Metro Manila.
300,000
250,000
200,000
150,000 No. of Septic
Tanks Emptied
100,000 No. of Households
Served
50,000
0
2007 2008 2009 2010
Year
Figure 6. Graph of Summary of Number of Desludging Service
Other local water districts are planning to employ similar initiatives to comply with the provisions
of the Clean Water Act of 2004. These local water districts are benchmarking Manila Water’s
desludging program. Manila Water continues to be a resource for these communities and
oftentimes provides working sessions to enhance education and awareness of septage management
programs.
Treatment and Disposal
Septage collected from septic tanks is transported to one of the two Septage Treatment Plants.
These world class plants have a combined capacity that is the largest in the world, employing semi-
automated treatment which involves minimal physical intervention from operators. The process is
conventional yet due to the varying content of septage collected from septic tanks across an
extensive service area, operational expertise is the key to guaranteeing compliance and maintaining
efficiency.

8. Figure 7. Septage Treatment Process Flow
Treatment Process. The first component of the process, known as primary treatment, involves the
removal of inert solids using septage acceptance units (screening and grit removal). At this stage,
the major problem encountered is the collection and disposal of large quantities of solid waste that
oftentimes contain items that can damage acceptance units. Apart from this, significant quantities of
oil, grease and industrial wastewater are sometimes encountered with concentrations above the
influent design capacity of the plant. In order to control these issues and protect plant operations,
plant personnel strictly monitor all tankers to perform the remedial measures and adjustments
required to mitigate damage to the plants.
Secondary treatment is applied through a conventional activated sludge process that cultivates a
culture of microorganisms in aeration tanks to address the organic contaminants of septage.
Considered the heart of the treatment process, these aeration tanks require meticulous process
control and operational expertise to guarantee that optimum conditions are provided to treat
contaminants. Microorganisms eventually settle to the bottom of the tanks as “sludge” while the
clear water above overflows for final disinfection prior to discharge.
Figure 8. Aeration Tank at South Septage Treatment Plant
Sludge is further dewatered via addition of polymers and mechanical compaction for stabilization
and subsequent reduction of volume. The dewatered solids or “biosolids” are then transported to
Lahar (volcanic ash) areas in the north for the primary purpose of soil conditioning. In 2009,

9. Manila Water generated 29,635 cubic meters of biosolids to assist in the rehabilitation of farmlands
in Central Luzon which were affected by the eruption of Mount Pinatubo. Through this approach,
Manila Water not only provided an economical and environmentally-sustainable method of
biosolids disposal, but ultimately delivered employment and agricultural benefits to a severely
disaster-stricken area.
Manila Water is also currently developing an enhanced management strategy for this material,
researching on viable technologies and operational schemes that can maximize the value of this
resource.
Figure 9. Biosolids from SpTPs are transported to Lahar Area
Operational Expertise. Operations and maintenance for these plants are performed according to
world-class standards, with one of the plants being certified under International Organization for
Standardization (ISO) in 2010 and the other currently undergoing similar certification. Through
operation of these facilities, Manila Water has developed a unique operational expertise that applies
both technical and non-technical solutions to address a variety of wastewater in an efficient and
cost-effective manner. In line with this, one of the most significant accomplishments with regard to
septage management is the development of Manila Water’s workforce into technically proficient
personnel capable of operating wastewater facilities with minimal supervision. Each plant manager
and operator is trained to be completely accountable for the area to which they are assigned,
ultimately developing a true “owner’s” mentality in plant operations.
This integrated operational approach maximizes the skill and geographic locations of personnel.
While operators and plant managers are accountable for centralized treatment facilities, desludging
managers located strategically throughout the eight business areas are responsible for the
decentralized collection of septage from individual households. Key management expertise
combined with appropriate allotment of manpower for labor-intensive activities, provide Manila
Water with a flexible structure that allows for the targeted implementation of septage services.
Monitoring and Evaluation
To assess the performance in implemeting it septage management programs, the company put in
place a performance measurement system that is anchored on quantifiable, measurable, specific and
realistic performance metrics. These are drilled down to the lowest operating unit. This system
provides a structure of accountability but also allows for a heightened analysis of operational targets
and efficiencies. Some of these common metrics are listed as follows:
 Service Levels: Coverage Area, Population Served, Households Desludged
 Operational Efficiency: Unit Costs for Desludging, Hauling, and Treatment
 Customer Service: Response Time
Ultimately, the MWSS Regulatory Office, DENR, and Laguna Lake Development Authority
(LLDA) provide and enforce wastewater standards for treatment operations and facilities. Since

10. commissioning, Manila Water’s septage treatment plants have been compliant with these standards.
Manila Water also endeavors to work closely with these agencies towards the ultimate goal of
rehabilitating Metro Manila’s water bodies: Marikina, Pasig, San Juan Rivers, Laguna Lake, and
Manila Bay.
Cooperative Policy Formulation and Insitutional Awareness Campaigns
In the Philippines, the solution to wastewater management is shared across various stakeholders.
While it is the concessionaire’s obligation to provide sewerage and sanitation services, these can
only be provided effectively within an enabling and supportive regulatory framework. Such a
framework needs to be strong, with clear accountabilities from the national to local government
levels. The need for these services needs to be clearly comunicated to residents of Metro Manila
and tied to the ultimate benefit to health and the economy.
Education and awareness are key to wastewater management, only with comprehension and
interventions on the household level can the true value of these services be realized. Recognizing
its role in this effort, Manila Water has intensified educational campaigns through the “Lakbayan”
or “Water Trails”, program which now serves as the primary tool for educating more stakeholders
on the benefits and challenges of water and wastewater service provision. Apart from this, the
Manila Third Sewerage Project also has an institutional awareness component which targets
communities where implementation of wastewater facilities is imminent.
These education and awareness activities, combined with a collective effort to develop and enforce
institutional policy, can greatly assist in the rapid implementation of effective wastewater
management for Metro Manila.
CONCLUSION
Manila Water has demonstrated that a septage management program is a viable method of
addressing pollution when applied with decentralized customer management, close coordination
with local government units, and effective and efficient technical operations. The success of septage
management in this, and other similar regions, depends largely on a fully integrated wastewater
management plan targeted at providing comprehensive service to customers.
REFERENCE
Business Model for a Water District Septage Management Program (2010, February)
Manila Water Sustainability Report 2009 Manila Water Company Inc., Manila, Philippines
EIS, Environmental Impact Statement for Manila Third Sewerage Project (2006,February). Volume
II: EMP Summary. Manila Water Company Inc., Manila Philippines
REA, Regional Environmental Assessment for Manila Third Sewerage Project (2006, February).
Manila Water Company Inc., Manila Philippines
Inocencio, Arlene B., Cristina C. David (2001, August). Public-Private-Community Partnerships in
Management and Delivery of Water to Urban Poor: The Case of Metro Manila. DISCUSSION
PAPER SERIES NO. 2001-18, Philippine Institute for Development Studies.
DAO 35, DENR Administrative Order No.35 (1990). Revised Effluent Regulations of 1990,
Revising and amending the effluent regulations of 1982