Willingness-to-Pay and Costs for Novel Manual Emptying Services for Shared Onsite Sanitation Facilities in an Informal Settlement of Nairobi, Kenya

Safely managed sanitation is essential for the environment and public health, yet emptying services for onsite sanitation are often unsafe and unaffordable. This study aims to assess the stated willingness-to-pay (WTP) for two safer manual emptying services. The first is referred to as the “Standard Plan”, a hypothetical safer manual emptying service, and the second is the “Small-amount Plan”, a hypothetical service with a volumetric limit. The service costs were also estimated to assess the financial feasibility. We surveyed 400 households in an informal settlement in Nairobi, Kenya, using a contingent valuation method: respondents answered two dichotomous questions about price bids and then a question about the maximum amount they could pay. The mean WTP for the Small-amount Plan was $1.4/drum─$0.2/drum lower than the WTP for the Standard Plan. While the WTP was lower, the estimated cost of the Small-amount Plan where emptiers can visit multiple toilets was $0.9/drum lower than the Standard Plan where emptiers visit one toilet. Our results suggest that grouping multiple toilets could be a market viable cost-reduction strategy for manual emptying and warrant further research to develop and test this approach, which may increase access to safely managed sanitation in low-income informal urban areas.