Expanding safe fecal sludge management in Kisumu, Kenya: an experimental comparison of latrine pit-emptying services

Most residents of Kisumu, Kenya, use latrines constructed over basic pits or attached to more durable concrete vaults and septic tanks. Only one-third of fecal sludge generated in the city, however, is safely collected and treated. Programs for improving fecal sludge management among poor households include the development of formal manual emptying organizations that are recognized by local authorities, employ safety procedures, and transport fecal sludge to a treatment site. In this study, we compared the financial structures of these organizations with those of vacuum trucks that primarily serve wealthier households. We also employed an incentives-based strategy to promote the expansion of safe pit-emptying services in a low-income area and compared the performance of three managing groups to coordinate these services: (1) The Association of Wastewater Managers (The Association); (2) a formal manual emptying organization; and (3) a community-based water supplier interested in coordinating emptying services. Vacuum trucks were more cost-effective than the formal manual emptying organization, and The Association was most efficient in servicing poor households. The Association also demonstrated the ability to service low-income areas comprehensively by delegating a fraction of jobs (11%) to formal manual emptiers in locations not serviceable by VTOs, and overall showed the highest potential to achieve pro-poor service delivery at scale.