Advancing sustainable wastewater management in Sri Lanka
Central Sri Lanka is home to sewerage systems that are about a century old. Their soak pits frequently overflow, leading to the contamination of nearby freshwater sources. This creates serious risks of waterborne illness, environmental damage, and loss of livelihood. With over 200 families and several hospitals depending on these systems for their daily water supply, an urgent upgrade to wastewater management infrastructure is needed.
Digging deeper into the wastewater issues
According to a 2023 UNESCO report, about 44% of global domestic wastewater was not properly treated before being released into the environment in 2020. This challenge is especially evident in Sri Lanka’s Central Province, a region famous for its vast tea plantations and significant contribution to the national economy.
However, some areas in the Nuwara Eliya district—a major tourist destination—continue to face wastewater treatment challenges that threaten public health and local ecosystems:
- Srinagar settlement – Home to approximately 800 people, this hilly, high-density community relies on a century-old sewerage system with soak pits that frequently overflow.
- Haputale Hospital – Built almost a century ago, the hospital can serve up to 500 patients and uses septic tanks and soak pits for wastewater management. An abandoned wastewater treatment plant nearby now releases contaminated water downstream.
- Rikillagaskada Base Hospital – Serving around 1,300 patients, this facility still depends on a basic septic system and soak pits, with no dedicated sustainable wastewater treatment plant.
Across all three locations, untreated domestic wastewater continues to be released into the environment, posing major risks to both public health and biodiversity. That’s why our Shelter mission team chose to focus on improving wastewater management in these critical areas.
Pooling the new and old together
In collaboration with UN-Habitat, the Shelter program’s team of engineers from the UK and India designed sustainable wastewater treatment and management solutions tailored to each site. To ensure community alignment, the team gathered feedback from residents, local engineers, and hospital management.
Land availability was a key consideration at the Srinagar settlement. To address this, we evaluated multiple viable locations for the new wastewater treatment facility and proposed diverting wastewater through older, still functional drains. Gravity-fed shallow channels would then guide the flow into the new treatment plant.
A visit to a supplier warehouse introduced the team to the Johkasou concept—decentralized, compact sustainable wastewater treatment units. Live demonstrations and performance tests at a hospital site provided valuable insights into system efficiency and field performance, helping refine our technical proposals.
Clearer waters ahead
Our designs aim to maximize the reuse of existing infrastructure wherever possible. For example, the team determined that Haputale Hospital’s older wastewater treatment plant could be rehabilitated. After assessing the structure’s condition, we recommended repairing cracks and reusing the plant to minimize waste and cost.
The Shelter team also developed recommendations for new infrastructure—including manholes, sewers, and modular treatment units—and produced preliminary sizing estimates for proposed package plant installations.
The result: a roadmap toward sustainable wastewater management that combines innovative technologies with the smart reuse of existing assets.