Background and context 

The cities of Wai and Sinnar in Maharashtra, India, face significant challenges related to untreated faecal waste disposal, inadequate desludging services, increasing environmental pollution, and a lack of effective wastewater treatment. In addition, regions like Sinnar experience water scarcity, necessitating innovative approaches to wastewater management and resource recovery. To address these issues, the cities have implemented solutions to treat wastewater and faecal sludge from on-site sanitation systems such as septic tanks.

Approach

The initiative introduced scheduled desludging services for septic tanks to ensure regular maintenance and prevent environmental contamination. Faecal Sludge Treatment Plants (FSTPs) with a 70 KLD capacity were constructed, utilizing pyrolysis technology in Wai for faecal sludge and septage treatment. Additionally, treated wastewater was reused for landscaping and urban forestry, with drip irrigation applied in Sinnar to support green spaces. Key stakeholders included the Wai and Sinnar Municipal Councils, a private operator managing the FSTPs, and Self-Help Groups (SHGs) responsible for landscaping and urban forestry in Sinnar. The initiative was supported by various funders, including the Bill and Melinda Gates Foundation (BMGF). Implementation steps involved developing Faecal Sludge and Septage Management (FSSM) plans, constructing FSTPs with support from multiple stakeholders, and assessing the quality and quantity of treated wastewater and sludge for reuse. Stakeholder consultations ensured alignment between municipal authorities, FSTP operators, and potential consumers of treated byproducts. Additionally, urban forests and landscaping areas were established using the treated outputs, with SHGs contracted to manage operations in Sinnar.

Outcomes and impacts

The initiative has yielded significant environmental and social benefits. On average, 20 kL of treated wastewater, 1,000 kg of dried sludge, and 39 kg of biochar are generated daily. The treated byproducts have supported the planting of over 1,400 trees from 16 species and the development of 8,000 m2 of urban landscaping and forestry. The urban forest has further contributed to carbon sequestration, reducing CO₂ emissions by 17,000 kg. Beyond the numbers, the project has enhanced urban aesthetics, increased biodiversity, and significantly reduced pollution from untreated faecal waste. 

Lessons learned

The strong ownership and commitment of municipal councils played a critical role in ensuring the project's sustainability. Evidence-based assessments helped in selecting viable reuse options, while active stakeholder engagement facilitated consensus-building and project acceptance. Additionally, the Maharashtra government has adopted a policy for treated wastewater reuse, assigning municipal councils the responsibility to implement similar initiatives. Inspired by the success of Wai and Sinnar, other cities such as Khopoli, Vita, and Satara have initiated comparable projects, demonstrating the scalability of this approach.