City to City Cooperation Project for Decentralized Sewerage Treatment Using Eco tanks in the City of San Fernando, La Union

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1 City to City Cooperation Project for Decentralized Sewerage Treatment Using Eco tanks in the City of San Fernando, La Union Draft Preliminary Report Evaluation of the Ecotank Project at Barangay Poro The San Fernando City Ecotanks project is a program of CITYNET ( ap.org), the United Nations Institute for Training and Research (UNITAR), and the Prince Albert II of Monaco Foundation. It was developed with the intention of demonstrating low cost and sustainable wastewater treatment technologies that can be adapted to site conditions in the Philippines. To achieve this demonstration, three sites were chosen in San Fernando City. This report details the program and installation at the first site, located at Barangay Poro. This Ecotank project serves 56 families or approximately 280 people. San Fernando City is quickly becoming the environmental capital of the Philippines. One of the first cities to develop a sanitary landfill, the city now boasts successes in demonstrating decentralized wastewater treatment. The city s first sewage system was installed for the public market and surrounding buildings in 2008 and continues to function today. A new wastewater system just completed serves the city owned slaughterhouse, and an EcoSan village demonstrating urine diversion toilets for a relocation community, developed in 2006 continues to garner international attraction. The Ecotanks project intends to demonstrate the next generation of decentralized wastewater treatment systems. It is designed to show how wastewater can be effectively managed by small communities through a step by step process for project implementation. This process includes: Performing an initial site assessment through rapid technical assessments and surveys; Collaborating with stakeholders and local residents; Promoting sanitation and hygiene to help raise demand; Planning the infrastructure by first properly characterizing the sources and site, and then selecting and sizing the wastewater treatment components; Installing the wastewater components in conformance with best practices; Developing an operations strategy and plan using local users to the extent possible; and Fostering an enabling environment that includes rules and procedures along with incentive programs.

2 The Ecotank projects have the potential to demonstrate how low cost and sustainable wastewater treatment systems may be installed to begin improving sanitation for defined point sources of wastewater. The Poro project is just the first step. Through the lessons learned, the next two Ecotank projects can be improved, so that through this effort, a defined and effective step by step process for developing sustainable wastewater treatment systems can be documented. SITE OF ECOTANK PROJECT (PORO CATBANGEN) The first stage of the project was to develop an Ecotanks installation at Barangay Poro to intercept a stream of wastewater from a small village that was flowing untreated into the river (see picture on right). Pictured above on the left hand side, you see the yellow line and boxes that indicate the location of the existing stream and proposed tanks. The idea was to intercept the flow from the stream and treat it in an Ecotank. During storm events, an overflow structure would allow stormwater to bypass the system. Poro represents a common scenario in San Fernando City and other urban areas in the Philippines: small groups of homes discharging untreated wastewater into a nearby surface water. A successful intervention such as what was anticipated for the Poro Ecotanks project could define a new paradigm in wastewater management in the Philippines.

3 The Poro site is especially challenging due to limited space and shallow soils. The system has been installed, but does not function properly at this time due to identified issues with the installation. Contractors are working to resolve the problems as identified below. The Poro Site Installation There are three major issues identified with the construction to date. These are: 1. Pipe elevations. It has been determined that the elevation of the connecting pipes is incorrect, which prevents water from flowing through the system. Indeed, during the time of the inspection, wastewater could be seen flowing through the original channel while no flow was observed discharging from the system. 2. Access ports. Tanks and sewers at this installation are covered by concrete slabs that are difficult to remove. They are heavy and present a hazard to the operator when lifting. They are also Final installation at the Poro site. Tank access ports, (manholes) should be provided with risers and lids above the finished grade for ease of service. installed in such a manner that opening them introduces sand into the system. Proper installation requires that gas tight locking manhole covers be installed that are at least 10 cm. above the finished grade wherever a tank access port is located, or over sewer components such as screens that must be serviced regularly. This will provide easier and more secure access to tanks and chambers. 3. Venting. Septic odors are now present in the alleyway near the homes. This appears to be a result of improper tank venting. A vent pipe should be installed directly from the Ecotank that terminates at roof level. In addition to the above construction issues, opportunities for improvement were found for the construction process itself. Care should be taken to ensure that the following process is followed for the remaining Ecotank projects, and wherever decentralized wastewater treatment systems are installed in the future. Issues identified with the construction process include: 1. Site plan. A site plan was prepared for this project, but did not accurately reflect the intended construction. The site plan should be prepared prior to construction to show accurately the location of property lines, Access cover includes an old sack covered by a heavy concrete lid. Proper covers should be elevated at least 10 cm above finished grade and have gas tight and locking lids.

4 buildings, the area where the tanks will be installed, the sewer lines, fence and any other feature that may affect the installation. The site plan should be fully dimensioned so that the contractor knows exactly where the tanks and associated equipment should be installed. 2. Design. An accurate, scaled design drawing should be provided prior to construction that shows the location of the tanks, elevations of the excavation, sewers, pipes and other features of the installation. It should provide a plan and profile view with all pipes and connections identified. Accurate construction drawings help to avoid problems such as pipes being installed at improper elevations. The drawings provided show the components of the project but do not provide enough details for proper construction. Pipe elevations required to provide positive flow through the system are not shown. 3. Soils evaluation. An analysis of the soils should be perform ed prior to construction that identifies soil depth. In the case of the Poro installation, rock was encountered when the contractor excavated the tank hole, which prohibited excavation to the required depth, which subsequently affected the installation of the pipes at their required elevations. Knowing soils limitations in advance would identify this limiting condition so that mitigating measures can be taken. 4. Tank installation process. It is apparent that the proper tank installation procedure was not followed. All wastewater tanks, including the future Ecotank installations should be installed using the following process: a. Over excavate the tank hole by a minimum of 10 cm. b. Install bedding material of sand or fine gravel at the bottom of the tank hole and level. This will protect the tank from sharp rocks. c. The Ecotank installation manual required installation of a concrete slab to which the tank will be strapped to prevent floatation. This method should be used at any installation where groundwater or floodwater may impact upon the tank. d. Back fill around the bottom half of the tank so that the top half of the tank is still exposed. Backfill with sand or soil that is free of rocks and debris. Lightly compact to eliminate air pockets around the tank.

5 e. Fill the tank with water to a point just above the half way mark and let sit for an hour. Any leaks will become apparent. Fix any leaks that may be found. f. Install all piping and double check that connections are tight and proper. g. Identify the elevation of the finished grade. Install manhole risers on the tanks so that the riser lids will be approximately 10 cm above finished grade. h. Install tank risers and lids. i. Call for inspection. Do not proceed with the backfilling around the pipes until the City engineer or their representative inspects the work. It is recommended to take photos and make measurements that will be shown on the as built drawings. j. Continue backfilling and compacting the soils around the tank and pipes taking care not to damage the piping. Use some water to help settle and compact the soils and manually tamp with hand tools to eliminate air pockets. Backfill to the finished grade. Provide a final grade that drains water away from the tanks. k. Continue the leak test by filling up the tanks to the full level. Let sit overnight and then refill as needed. Then after one hour record any drops in water level. If the water level in the tank drops more than ½ cm in one hour, there are leaks that must be repaired. If no leaks are found, a written certification by the contractor shall be provided along with the as built drawings. 5. As built drawings. As built or record drawings that accurately detail the construction should be provided. As built drawings are prepared by using the original construction drawings, and with a red pen, correcting the original drawing with the actual installed features. They should be complete with accurate measurements. Accurate as built drawings help to identify and troubleshoot problems that may develop once the system is turned over to the owners. The Project Development Process Ensuring community involvement through a bottom up planning approach is required to achieve long term desired outcomes. While some consultations with the Poro community occurred, more are needed to continue to drive the interest in proper sanitation and ultimate long term support for the project. For future projects, more consultations during initial project planning would help ensure sustainability. These Ecotank projects are ideal entry points for educating the target community about environmental health, hygiene and sanitation. Evidence at the site indicates that this message has not gotten through. Indeed one home, located right next to the wastewater system still has a wastewater pipe that discharges on the ground. This could easily be fixed through a simple connection to the sewer line. Barangay Health Workers, schools, and barangay officials should all be helping the city get the message across. The bottom up planning process that considers the needs, wants and desires of local residents is critical to success and sustainability.

6 Recommendations for better project design for future decentralized wastewater projects: There are many lessons learned from the Poro installation that will make future projects better. Evidence based behavior change promotions campaigns. Even though these are small projects, it is important to collect evidence on the key motivators of the people served by the project. The Poro project did perform some surveys and rapid assessments, but more frequent meetings and focus group discussions prior to project implementation could have helped to better understand local needs, which then could be used for launching effective campaigns to drive demand. Identifying the motivators; why people should want to have wastewater systems and then promoting the project by addressing these motivators was not adequately performed. Therefore local interest and support for the project remains weak. Incentives. Incentives are a key component of sustainability for a project such as Poro to help motivate people towards appropriate behavior. Incentives such as reducing fees if local users help to maintain the sewer systems by removing trash and debris is one proven method of increasing local support for a project. It helps to keep the system functioning properly by having the local users engaged. People are less likely to throw trash if they are the ones that have to pick it up. The same concept goes for sewerage. People will care for their sewer systems better if they are the ones performing the maintenance. Demand Driven Programs. The Poro project was simply given to the people. They didn t have to work for it, care for it, or even care about it. Life will go on just as it did before without people thinking twice about wastewater or sanitation. This is a poor formula for effective development. Much better would be to spend some time in educating people about the problems of untreated wastewater and the direct link to disease. Then augmenting this argument for sanitation by addressing the key findings about the motivators learned from the surveys and assessments. Once people understand the problem, see the solution as addressing their needs, the demand will follow. Engaging local users in the system design and oversight of the installation. The more people are involved in every aspect of the project, the better they will understand and support the system through proper actions and behaviors. Unregulated sewage discharge located 3 meters from new treatment system. This pipe could easily be connected to the new system. This indicates a low level of understanding of the program by both the local residents and project implementers as well. Sustainable Sewerage Because the sewer runs right through the alleyway in close proximity to dwelling units, it is most important to engage the local residents in managing the sewer collection system.

7 According to the city engineering office, as a component of the sewer line, the city installed screens, capped by large and heavy concrete slab covers (shown here). The screens are a high maintenance component that depending upon the behavior of residents related to solid waste management, may require frequent if not daily cleaning. Unfortunately, the heavy concrete lids make this task difficult. It is likely that this will be a continued operational problem. Sewer maintenance is another opportunity for engaging the local residents in the project. Through incentives, such as those referenced above where fees can be reduced through maintenance labor, local residents have increased ownership of the project and more of an interest in properly operating and maintaining it. It is not too late for the city to implement such an incentive program. With the passing of the revised sanitation code, residents must now pay a wastewater fee to the city. The fee could be reduced through cooperative activities by local residents. Additional Points and Lessons Learned The promise of the Ecotank project is that EcoTanks represent a low cost and simple method for wastewater treatment and sanitation improvements. The product literature states: Eco Tanks are innovative small scale sewerage treatment systems composed of a disposal tank that receives and purifies wastewater before discharging it into the environment. The compact, readymade septic tank works independently and without power supply using anaerobic bacteria to biochemically transform wastewater into a safe, non contaminated effluent. The experience to date does not support this claim, although the next two installations may help make this case. Some issues: 1. Ecotanks delivered from Thailand are expensive, not low cost. Add in the cost of installation, purchase of land, time of city officials and staff and the cost if installation, the overall cost of the project is quite high. The cost of freight from Manila to San Fernando City alone is expensive. It is believed that Ecotanks made of fiberglass would only be cost effective if manufactured locally. Local contractors can build tanks similar to Ecotanks out of concrete much more cost effectively. 2. Other expenses, including the site preparation, land acquisition, and payment to contractors makes these very expensive projects. Understanding the costs involved earlier on in the process would have been useful to the city. This is a lesson learned for future projects. 3. The Ecotank at Poro is a primary treatment device, just like a septic tank. There is no secondary treatment system that would make the effluent suitable for discharge. A secondary treatment device, such as a planted gravel filter or other media filter would be required to make this a compliant system and then disinfection would be required to meet the claim of safe, non

8 contaminated effluent. The next Ecotank installation at Catbangen is designed with a proper secondary treatment device to address this need. Likely the Poro site will need to be augmented with a secondary treatment component to meet discharge requirements. 4. More training on the proper installation methods. There were two trips to Thailand by city officials to highlight Premier Products technology, but none involved technical staff from the city in hands on workshops to learn the proper method of tank installation. This type of training would eliminate many of the problems found with the Poro installation and is needed for scaling up sanitation from the demonstration project to wide scale sanitation improvement. 5. Over selling the product. While manufacturers typically are most enthusiastic about their products, it is important not to over sell the capabilities of installed systems. Over selling raises expectations and makes it very difficult to deliver upon key promises made to satisfy the motivators identified during surveys. Failure to deliver upon key promises severely limits sustainability and any likelihood of replication. Conclusion This is a preliminary report. It is submitted now to provide guidance on next steps for correcting deficiencies at the Poro installation as well as in developing a better approach for the next Ecotank installations in San Fernando City. There is still a great potential for the Poro project to achieve desired goals but more effort is required. This will include correcting the construction deficiencies, re engaging the community through a continuous outreach program, and developing incentive programs where local residents have a stake in proper operation and maintenance of the facility. The stakes on this project are high. Failure would be a strong indication that decentralized wastewater treatment doesn t work and money would be better spent elsewhere, while success would help promote a new paradigm for community wastewater management in the Philippines.