Kigali is characterized by hilly terrain and dense informal settlements, where around 60% of residents live in hard-to-reach areas. Exhauster trucks are often unable to reach households and the hilly terrain limits how far these trucks can pump.  

• Among the technologies tested, the Pitvaq and Gulper 4 performed best in these hard-to-reach areas. Both pump faecal sludge into barrels that workers can carry by hand to the nearest accessible point, allowing them to serve homes well beyond the range of a truck or the PuPu pump.  
• In one extreme case, a Pitvaq emptied a pit 500 metres from the nearest truck access — a distance that would have left the household unserved by any truck-based method. 
• Where possible, the preference would be for the exhauster truck or Pupu Pump as it reduces barrel carrying and physical effort. Technologies that enable direct pumping to trucks with minimal setup consistently rank higher. But in hard-to-reach areas, the Pitvaq is preferred over the Gulper.  
• Our research in Kigali shows that technology performance cannot be judged by pumping time alone. In hard-to-reach areas, set-up time, barrel carrying, transfer arrangements, and travel distance to disposal sites can be as important as the emptying technology itself. 

Figure 1. Typical hillside settlement in Kigali, where dense housing on steep slopes places many homes beyond the reach of exhauster trucks.

Context and Challenge 

Home to 1.7 million people, Kigali is characterized by hilly terrain and dense informal settlements, where around 60% of residents live in hard-to-reach areas. In those unplanned settlements, many homes sit more than 50 metres from the nearest road where an exhauster truck can park, and the hilly terrain further limits how far these trucks can pump. These conditions make pit emptying difficult, with exhauster trucks often unable to reach households. Of Kigali’s 21 licensed pit emptying service providers, only two use semi-mechanized portable technologies, enabling them to serve hard-to-reach settlements. Pit Vidura remains the most active among these providers. 

Technology Deployment 

In Kigali, the FSM Action Research Project tested the Gulper V4, Pitvaq, and Pupu Pump in informal and peri-urban settlements. The job distribution map shows that emptying jobs are concentrated within Kigali’s dense central core, across the adjoining sectors of Nyarugenge, Gasabo and Kicukiro, with little activity in the outer sectors. 

Spatial Distribution of Fecal Sludge Emptying Technologies Across Kigali City, Rwanda 

During the study, the exhauster truck was the default wherever a household could be reached from a road, and portable technologies were deployed only where the truck could not operate. 

Among the technologies tested, the Pitvaq and Gulper performed best in these hard-to-reach areas. Both pump faecal sludge into barrels that workers can carry by hand to the nearest accessible point, allowing them to serve homes well beyond the range of a truck or the PuPu pump. In one extreme case, a Pitvaq emptied a pit 500 metres from the nearest truck access — a distance that would have left the household unserved by any truck-based method. 

Emerging Operational Points 

Focus group discussions ranked technologies in order of preference as: Exhauster Truck → Pupu Pump → Pitvaq → Gulper V4. 

Preference was largely driven by reduced physical effort, particularly avoiding barrel carrying and minimizing equipment transport time. Technologies that enabled direct pumping to trucks with minimal setup were consistently ranked higher. 

The Kigali experience shows that technology performance cannot be judged by pumping time alone. In hard-to-reach areas, set-up time, barrel carrying, transfer arrangements, and travel distance to disposal sites can be as important as the emptying technology itself. 

Pitvaq appears to be an important technology in Kigali, but its efficiency depends on the surrounding transport system. Where barrels must be carried or transferred, the full operation needs to be assessed from pit to disposal point. 

Testing these technologies in Kigali’s informal settlements demonstrated that safe and hygienic pit emptying is possible even in steep, congested areas where trucks cannot operate. 

Technology Jobs recorded	Technology Jobs recorded
Gulper V4	48
PuPu Pump	50
PitVaq	50
Vacuum truck	50
Total	198

Table 1. Jobs recorded per technology in Kigali