Kigali’s quest for sewerage system

The city of Kigali’s plans to construct a central sewerage system was one that met the approval of the majority. It would be the best thing to do to contain flooding in the city that is often a menace during heavy rains.
Nzove water plant treatment in Nyarugenge District. Timothy Kisambira.
Nzove water plant treatment in Nyarugenge District. Timothy Kisambira.

The city of Kigali’s plans to construct a central sewerage system was one that met the approval of the majority. It would be the best thing to do to contain flooding in the city that is often a menace during heavy rains.

However, despite the looming rains, it remains unclear when plans to construct the city’s central sewerage system will eventually kick off.

Kigali’s infrastructure continues to grow at an unprecedented rate, with more buildings set to be unveiled in the near future.

However, people have to build their own septic tanks and or mini waste treatment plants, all at an extra cost.

“As a city, a central sewerage system is needed. Presently, it is expensive for developers in the city given that a mini sewage plant costs about five percent of any construction project in the city,” said City of Kigali’s director of media and communication Bruno Rangira. 

“Once we get the central treatment plant, construction costs will significantly reduce.”

New City buildings are required to have a mini sewage treatment plant. Currently, to establish a mini-waste treatment system, developers must part with between three and five per cent of the total project’s cost. 

If a central sewerage system existed, however, developers would not need to include such sewage management systems in their designs as they would be connected to the central network.

“Even small buildings have septic tanks which are emptied regularly but this, too, is an added cost making property development expensive. A central sewerage system would also be good for sanitation,” Rangira added.

Health concerns

Normally, networks of central sewerage collection and disposal systems transport sewage through cities and other inhabited areas to sewage treatment plants to control water pollution before discharge into surface waters.

But this is not the situation in Kigali since people either dig pits, construct septic tanks and semi-waste disposal plants, an arrangement which, according to health experts, is no guarantee for good public health.

Dr Daniel Nyamwasa, director of Kacyiru Police Hospital, said normally there should be a central sewerage system to help check environmental dirt and pollution so that people are assured of having safe water.

The untreated dirt that seeps into water systems causes infectious diseases, disorders caused by organisms such as bacteria, viruses, fungi or parasites, including cholera and Hepatitis A.

Dr Nyamwasa said the concern should also be looked at another angle since the lack of a central sewerage system also negatively impacts on “the economics of water.”

“With such a system in place, dirty water could be treated and made safe for re-use. We wouldn’t have the water issues that we have,” he said.

The government is looking into ways to establish the first ever central sewerage system. A sewage treatment plant will be constructed at the Giti Kinyoni area in Nyarugenge District.

Consultants from the Mott MacDonald Group, a UK-based multidisciplinary consultancy company, are drawing the designs on the entire system – a network of pipes that will run through the city – up to the sewage treatment plant.

Set for long wait?

James Sano, the managing director of the newly-created Water and Sanitation Corporation (WSC), however, cautioned on the timeline of the project. 

The consultants will first provide engineering designs and requisite tender documents. WSC will then advertise to find the best constructing firm.

“We are working hard but it is not a straightforward thing. You don’t have to be very optimistic in terms of when the central sewage system will actually be in place,” Sano said.

“There are things that have to be done first, one of which is the designs. But the most important thing is that we have to raise 70 million Euros [for construction]. We are on studies and three studies have to be carried out. 

“One is on engineering designs but there will also be a resettlement action plan (Rap) and a social and environmental impact assessment.”

The central sewerage system, to be assembled in phases, will be a network of underground pipes connected to buildings in the city, and eventually emptying into a sewage treatment plant, as per the set city sanitation master plan.

Sano said in May, 70 per cent of the designs work was complete.

Today, he said, the design is at 80 per cent on the [pipe] network and on 75 per cent on the treatment plant. 

“But progress at the treatment site is not moving quickly because we have to clear issues of expropriation [on small patches of land where pipes will pass],” he added.

The work on designs, which is being funded by the European Investment Bank (EIB), will be completed “around December.”

Sebastien L. Mellot, a Mott MacDonald engineer with 10 years’ experience in water and sanitation sector, told The New Times that their current job includes mapping where the pipes will be and ensuring that “the pipes will be safe.”

“We have a model and now we are doing a reality check to ensure that what was designed on the computer is working,” Mellot said. 

Mellot’s own assessment of the city’s sewerage system is that it is a “major” issue. He said the WSC is “doing the right thing to address the rapid urbanisation of the city” and also needs to “address potential sanitation issues which will become critical.”

Putting the system in place, he said, is “going to be demanding” but it is worth it since it is a long-term investment since “the lifespan of these pipes is for about 50 years, minimum.”

“The WSC, through the development of this infrastructure is going to offer a new service because people will connect and not have a septic tank anymore. Just like they have a water bill they will also have a sewage bill just like it is done in other places.”