2013年-世界发展银行全球_Review_of_Community-Managed_Decentralized_Wastewater_Treatment_Systems_in_Indonesia_32页_2mb

Summary of "Review of Community-Managed Decentralized Wastewater Treatment Systems in Indonesia"

Core Content

This report provides an in-depth review of Indonesia's implementation of Community-Managed Decentralized Wastewater Treatment Systems (DEWATS), particularly focusing on Sanitation by Communities (SANIMAS), as an intermediate solution to urban sanitation challenges. It evaluates the effectiveness, sustainability, and scalability of these systems and outlines recommendations for their successful integration into broader urban sanitation strategies.

Main Points

Definition and Types of DEWATS

• DEWATS refers to passive anaerobic treatment systems.
• The most common technology used is the Anaerobic Baffled Reactor (ABR).
• There are three main types of DEWATS in Indonesia:
  • Community Sanitation Centers (CSCs): Serve 20–100 households, with toilets, washing, and laundry facilities.
  • Simplified Sewer Systems (SSS): Collect wastewater from households and gravity-feed it to a DEWATS plant.
  • Combined Systems: Integrate local sewer networks with communal sanitation facilities, serving both connected and unconnected households.

Indonesia's Urban Sanitation Challenges

• Only less than 2% of the urban population is connected to a centralized sewer system.
• Most urban residents rely on on-site sanitation, such as septic tanks or soak pits.
• Open defecation and the use of 'helicopter toilets' are still prevalent.
• Water pollution is severe, with 66% of the urban population lacking access to piped water and relying on untreated groundwater.

Role of DEWATS

• DEWATS are seen as a viable alternative to centralized systems in low-income, densely populated areas.
• The Government of Indonesia aims to reach 5% of the urban population (6 million people) with DEWATS by 2014.
• These systems are cost-effective when serving more than 50 households, and can improve environmental health and hygiene behaviors.

Key Findings

Operational Performance

• >80% of DEWATS installations are functioning well and comply with environmental regulations.
• Simplified sewer systems are the most resilient due to low maintenance and operating costs.
• Community management is often inadequate or informal, with many structures not functioning as intended.

Sustainability Issues

• Lack of motivation among community management structures.
• Inadequate operating income for major repairs.
• Limited concern for wastewater treatment performance compared to convenience and privacy.
• No external support when problems arise, leading to dysfunction in some systems.

User Behavior and Responsibility

• Desludging is often not seen as a responsibility by users.
• Users prioritize convenience and privacy, which SSS systems provide better than CSCs.
• CSCs are most effective in areas with high tenant populations and no space for individual toilets.

Government and Institutional Role

• Local government is formally responsible for sanitation but lacks institutional capacity.
• NGOs have played a key role in implementing DEWATS, but their methods are not easily replicable at scale.
• Post-construction support is lacking, with no monitoring or training systems in place for long-term maintenance.

Recommendations

Institutional Roles, Sustainability, and Urban Integration

• Integrate DEWATS into city-wide sanitation plans that identify which areas will use decentralized or centralized systems.
• Move from "Sanitation by Communities" to "Co-management", where:
  • Communities manage day-to-day operations and minor repairs.
  • Local government and private partners provide sustainability support, including desludging and major maintenance.
• Develop co-management capacity in local government as part of its institutional models.

Technical Aspects

• Ensure proper design and location of DEWATS to maximize user engagement and system effectiveness.
• Include secondary and tertiary treatment where feasible, though most systems do not use planted gravel filters due to space constraints.

Financial and Economic Aspects

• Cost-effectiveness increases with more users per site.
• Government should provide financial incentives for cities to establish municipal wastewater utilities.

Equity and Pro-Poor Aspects

• DEWATS are especially suitable for low-income, densely populated areas.
• SSS systems are more user-friendly and sustainable in the long term.
• CSCs are best suited for areas with non-permanent residents, space constraints, or flood risks.

Overall Assessment

• Community-managed DEWATS can be effective in improving sanitation, especially in underserved urban areas.
• They are not a substitute for government responsibility in sanitation planning and management.
• Sustained success requires external monitoring, technical support, and shared responsibility between communities and local authorities.

Next Steps

• Scale up DEWATS implementation in alignment with national sanitation goals.
• Develop co-management frameworks that include technical and non-technical support.
• Integrate DEWATS into broader city sanitation strategies, ensuring long-term sustainability.
• Improve post-construction support through monitoring systems, training, and referral mechanisms.

Conclusion

Community-managed DEWATS have shown promise in improving sanitation in underserved urban areas of Indonesia. However, their long-term success depends on structured co-management, adequate government support, and proper planning. They are not a standalone solution, but rather a complementary approach to integrated sanitation improvement.