The Sustainability and Scalability of Private Sector Sanitation Delivery in Urban Informal Settlement Schools: A Mixed Methods Follow Up of a Randomized Trial in Nairobi, Kenya.

There are considerable challenges to achieving the Sustainable Development Goals' target of universal access to basic sanitation in schools. Schools require safe, clean, and sex-segregated facilities for a large number of students. Robust and affordable solutions are needed to address the economic, spatial, social, institutional, and political factors which contribute to poor sanitary conditions in informal settlements. In 2015, we undertook a randomized controlled trial to assess the feasibility of private sector sanitation delivery (PSSD) in 20 primary schools, in informal settlements of Nairobi, Kenya. Our preliminary evaluation after one year of service delivery suggested that PSSD of urine-diverting dry latrines with routine waste collection and maintenance provided a feasible, lower-cost alternative to the government standard delivery (GSD) of cistern-flush toilets or ventilated improved pit latrines. We conducted a mixed-methods follow-up study to assess sanitation delivery over 3-4 years and investigate prevailing drivers and barriers that may influence the scalability of PSSD. The conditions of newly constructed and rehabilitated GSD facilities diminished quickly, reverting to the conditions of existing facilities, indicating lower sustainability compared to sanitation delivered from the private sector. Barriers in financial aspects related to the ongoing implementation of PSSD emerged, particularly among public schools, and few were able to pay for continued service. Our study demonstrates that the engagement of the private sector may lead to improvements in affordable, safely managed sanitation for schools and their students. Yet, to reach a sustained scale, additional guidance is needed on how to develop these partnerships, streamline procurement and contracting processes, and incorporate appropriate financing mechanisms.