El Nido’s state-of-the-art sewage and solid waste treatment plant (SSWTP), the first in the country which can convert biodegradable garbage into electricity, is seen as a long-term solution to the tourist town’s water pollution and waste disposal problems.
The P490 million facility in a two-hectare land area was inaugurated Monday, September 20, in Sitio Batbat in Barangay Villa Libertad led by Palawan Governor Jose Alvarez, El Nido Mayor Edna Gacot-Lim, and other provincial and municipal government officials.
It is a strategically located solar and biogas-powered treatment plant that can remove 2,400 cubic meters (m3) of contaminants per day from sewage with sewerage pipeline system coverage equivalent to 90 percent of the existing buildings in the barangays in El Nido’s town proper.
The SSWTP can treat 20 metric tons (MT) of non-toxic solid waste equivalent to 100 percent coverage of biodegradable waste generation of the entire municipality and can generate 240 kilowatts (kW) of electricity representing 20 percent of El Nido’s total power demand.
The treatment process at the facility starts with the collecting of waste matter from buildings through an underground network of sewage pipes and transferring it to cluster collector tanks.
“May naka-layout ng linya sa bayan ngayon, sa buong streets ng poblacion ng El Nido. Underground yon, malalim siya. Yong sewerage system na yon, ikokonek siya sa mga commercial establishment and household para yong lahat ng kitchen liquid, [from] toilets, at saka yong overflow ng septic tanks [doon siya pupunta]. Ikinonek natin yon sa collector tank, nilagyan ng solar pump para yon ang mag-transport ng wastewater papunta dito sa STP,” explained Engr. Ann Michelle Cardenas, program manager of the utility infrastructure project Palawan Water.
Sewage in the collector tanks is then pumped using an off-grid solar pumping system with a 275 kW power capacity, delivering it into the treatment plant, which is located five kilometers away from the poblacion.
It will then undergo primary, secondary, and tertiary treatment using the following: activated sludge process, tube settler, and dual-stage filtration technology which produces final effluent water– wastewater that passes the standard set by the Department of Environment and Natural Resources Water Quality Guidelines and General Effluent Standards of 2016.
Engr. Cardenas said if waste segregation is strictly enforced, the objective in a year or two is to have surplus electricity that may be supplied to nearby homes.
Lim said the municipal government has purchased nine waste collector trucks for some barangays to help with the gathering of biodegradable domestic waste.
No connection, no permit
She said that all businesses in El Nido’s downtown core barangays (Buena Suerte, Corong-Corong, Masagana, and Villa Libertad) must be connected to the facility, or the municipal government would refuse to grant them their required permits.
She said an amount will be collected from the business establishments for the connection through an ordinance that has to pass through the municipal council.
“Mayroon silang babayaran doon sa koneksyon, aayusin pa yong ordinance,” Lim said.
“Lahat ng mga business establishment dito sa El Nido, ready na sila sa mga requirements. Hindi ako mag-i-isyu ng mayor’s permit kung walang koneksyon, kasi dapat isasara ang El Nido, kaya lang yong ibang mga establishment talaga gumawa sila ng paraan na magkaroon ng STP, pero willing naman sila na mag-konek,” she added.
The sum that would be collected would be “far lower” than the estimated P800 septic collection fee in Manila, according to Engr. Cardenas.
Sewage treatment plant development
The proposal to build a sewage treatment plant in El Nido began in 2016 during Lim’s administration but was stalled when municipal leadership changed to then-mayor Nieves Rosento. It was revived in 2018 after President Rodrigo Duterte temporarily closed Boracay due to deteriorating sewage conditions.
Duterte had ordered Secretary Roy Cimatu of the Department of Environment and Natural Resources (DENR) to address the island’s environmental problems, as well as inspect other important tourist sites in the country, including El Nido.
Cimatu, who visited El Nido in November 2018, did not order the town’s closure but emphasized a six-month rehabilitation program aimed at improving the town’s water quality and enforcing coastal easement and carrying capacity restrictions.
Cimatu instructed the local administration to ban swimming at the beach in Brgy. Buena Suerte as part of the rehabilitation plan due to high fecal coliform bacteria levels of 1,300 parts per million (PPM). The town’s primary sewer discharges household wastewater into the sea via the barangay.
“Itong pasilidad na ito, one of its kind in the Philippines na pinagsama yong sewage, meaning to say yong mga dumadaloy mula sa ating mga palikuran, kasama po ang solid waste na tutunawin dito sa dalawang malalaking digesters,” Gov. Alvarez said in his speech during the inauguration Monday.
“Ito ay very difficult project that the provincial government has embarked on, kasi po katugunan ito noong tumaas yong E. coli sa El Nido bay. DENR raised the red flag,” he added, additionally describing it as an “engineering challenge” to complete.
The sewage and solid waste treatment plant were previously estimated to cost about P661 million, shared between the provincial government and El Nido. The province will provide P470 million, or 71% of the overall project cost, while the town would contribute P191 million, or 29%. The funds were taken out as loans from the Development Bank of the Philippines (DBP).
Alvarez said Engr. Cardenas’ feasibility and engineering design work through the i-Support Water Infrastructure Office, which included the free use of the province’s heavy equipment, resulted in a cash savings of about P170 million, effectively lowering the cost of building the Philippines’ one-of-a-kind SSWTP.
According to the provincial government, the SSWTP was completed not only to protect El Nido from the detrimental effects of water pollution but also to provide an income-generating project for the town.
The investment’s payback period is expected to be 10 years, with an internal rate of return of investment of 12 percent based on the estimated rate of revenue production.
The facility also has a laboratory that is equipped with a complete set of analyzers that provide round-the-clock monitoring of the plant’s effluent discharge.
The septage and biodegradable solid waste go through a different treatment termed “anaerobic digestion,” which is a natural process in which microorganisms break down biodegradable materials in the absence of oxygen and subsequently convert it to biogas fuel.
A 300 KVA Biogas Generator is then utilized to produce power from this fuel. The electricity produced by solar energy is utilized to power the whole complex.
Each process in the treatment plant is monitored and commanded at the Control Tower, which is equipped with Supervisory Control and Data Acquisition for high-level and automated supervision of machines and processes.
Participating in the completion of the SSWTP were engineering graduates from Palawan State University (PSU) and Western Philippines University (WPU). Some were also on-the-job trainees before they took their engineering board. One of the architects was also a graduate of PSU.