Adapting Sanitation Projects to Climate Change in the Philippines

Retrofitting, Upgrading Septage & Wastewater Treatment Systems

Basic Needs Services (BNS) Philippines, Inc., BORDA’s partner organisation in the Philippines, extended its collaboration with 15 cities/municipalities in 2019–2020 to introduce and amplify an integrated sanitation approach for the benefit of around 100,000 people.

As climate change impacts have begun to challenge even the most technologically sound and innovative solutions, cities and municipalities need to adapt and/or retrofit sanitation systems to be climate-resilient. To provide insight into possibilities for making existing and future investments climate-resilient if not climate-proof, BNS shares here its approaches to mitigation and adaptation in La Union Province north of Manila, and other regions in the Philippines.

• Climate change increases the frequency of extreme precipitation. In Sorsogon Province, the public market DEWATS project has experienced climate change-induced phenomena like intensified rains and increased flooding, which are harmful to wastewater treatment infrastructure. To reduce the risk of structural damage, BNS introduced deeper trenches and installed a breakwall to induce water flow in the flat terrain of the treatment facility site.
• Reduced/minimised/limited use of fresh water is incorporated into the in-house management of the Bureau of Animal Industry (BAI)’s Animal Product Development Center (APDC) in Valenzuela City. In addition, the slaughterhouse utilises biogas from the digester to reduce its reliance on LPG and other fossil fuels.
• Reuse and recycling of DEWATS-treated wastewater is now in practice at most sites as part of their improvements/upgrades. Storage tanks were installed for this purpose, such as those at Ateneo de Manila University in Quezon City; Rosario District Hospital in the Municipality of Rosario, La Union; and Caba Medicare Community Center in Caba Municipality, La Union.
• Treated sludge from the Bauang SSTP in La Union will be reused as a natural fertiliser and plant growth enhancer in denuded areas, thus producing oxygen in the municipality’s open spaces.

Reducing Emissions from Septage Treatment

While climate change impacts on wastewater and septage treatment infrastructure, the latter also contributes to climate change. Treatment processes naturally give off major greenhouse gases. Thus, BNS has incorporated methane gas capture from the biogas digesters in several projects including the Bauang slaughterhouse (for cooking food at the municipal jail facility), the Bacnotan and Balaoan slaughterhouses in La Union Province (for heating water), and the Sta. Cruz slaughterhouse in Laguna Province.

BNS has made more use of anaerobic treatment, which is proving to be an attractive component compared to pond systems. For the stabilisation of sludge from septage, BNS introduced stabilisation reactors, aside from methane gas capture, in the septage treatment facility in Barangay Payucpoc, Municipality of Bauang, La Union.

Upcoming BNS projects include the septage treatment plant in Bacnotan Municipality in La Union and a community-based sanitation project in Sitio Baroro in Bacnotan. All anaerobic tanks in BNS-assisted city/municipal DEWATS projects will shift to solar energy to power their pumping systems.

Food for Thought

Funding – To justify the required additional investments to make treatment systems climate resilient, cities/municipalities need to know their optionsand the corresponding costs. Indeed, adapting to climate change will add to the already substantial financing gap for sanitation in the Philippines, as in the rest of the world. It also raises several specific challenges for financing. Climate change adaptation needs to be mainstreamed into water and sanitation policy objectives at least cost. Nevertheless, adaptation funding should be built upon sound approaches and demonstrate value for money.

Blended infrastructure – Making water and sanitation systems climate-resilient does not imply the need to abandon traditional infrastructure, but rather the wider adoption of blended grey–green–blue infrastructure, which can be more cost effective, less vulnerable to climate change, offer mitigation co-benefits, and provide better service and protection over its lifetime.