Recurrent floods that have been affecting Nyabugogo, Kigali’s commercial hub hosting the main terminal for commuters to different parts of the country could soon end following multi-billion facilities including new Muhazi dyke being constructed to control floods.
The area is between Nyabugogo River and Mpazi drainage that usually flood and affect businesses.
Researchers warn that businesses around Nyabugogo River and its other water catchment areas in Kigali could face further losses due to flooding if no urgent actions are taken to address the problem.
Some vehicles stranded at a flooded road at Nyabugogo in 2019. Photo: File.
According to studies, small businesses in the area lose Rwf178.2 million annually due to the recurrent floods to which Nyabugogo River also contributes.
The Nyabugogo River is 45.97 km long, measured from the outflow of Lake Muhazi in Eastern province to its confluence with the lower Nyabarongo River near Kigali.
Davis Bugingo, the Flood Management and Water Storage Development Division Manager at Rwanda Water Resources Board (RWB) said that the construction of a new Muhazi dyke that will cost Rwf3 billion to lessen floods towards Nyabugogo commercial hub will be completed soon.
"The current unprotected dyke breaks and has the potential of flooding the Nyabugogo area which is a commercial hub in Kigali city to cause significant damages of properties and lives. The new dyke is very crucial in fighting such problems,” explained Bugingo.
Dyke is a long wall or embankment or a barrier built to prevent flooding by regulating or holding back water from a river, lake, or even the ocean.
Lake Muhazi, which is a flooded valley lake where the dyke is being constructed, spans over around 38 km.
Drained by the Nyabugogo River, the lake empties into the Nyabugogo River, which flows southwards to Kigali where it meets the Nyabarongo River, part of the upper Nile .
An integrated water resources management plan shows that three main packages namely urban flood control and Nyabugogo wetland restoration in Kigali, protection of Lake Muhazi through promotion of non-consumptive and efficient water use as well as catchment restoration, farmland improvement and rainwater harvesting could reduce the floods.
The new Muhazi dyke being constructed by China Geo Engineering Corporation, to replace the current old one, will be 6.5m high with crest elevation of 1437.5 m where it is anticipated to be completed in September 2021.
The current old dyke was constructed in 1999 as an emergent solution, but the lake was drying due to an uncontrolled outlet.
Businesses in the Nyabugogo area have requested the government to fast-track the flood control facilities as rainy seasons are starting.
Pierre Muhire, a businessman who trades food and drinks around Nyabugogo bus terminal recalls the time his shop was submerged with floods in April last year.
"The water comes from different corners especially Mpazi drainage and Nyabugogo River. I incurred a loss of about Rwf60 million and I have not yet recovered from the losses due to additional effects of Covid-19. It is better the construction of flood control facilities we are seeing be fast-tracked before rainy seasons hit us again,” he said.
Muhire said that he has been struggling to pay back bank loans due to the huge losses.
Mpazi drainage expansion
The City of Kigali has also started to rehabilitate and expand Mpazi drainage that has been causing floods.
The drainage collects waste and rainwater from homes in the sectors of Nyamirambo, Gitega and Kimisagara all in Nyarugenge, towards Nyabugogo.
During heavy rains floods destroy several properties and carry the debris all the way to the Nyabugogo valley.
The project to cost Rwf8 billion started with expanding two major bridges to enable direct flow of drainage water into Nyabugogo River.
Kigali city also seeks to rehabilitate and expand several drainages that usually cause flooding in the country’s capita which is requiring Rwf30 billion funding.
Over 40 drainages need rehabilitation and expansion according to officials.
Last month, Parliament approved €6 million (Over Rwf7 billion) financing from Nordic Development Fund (NDF) to control floods and construct drainages in Kigali City.
Under the financing arrangement, €4 million is a loan while €2 million is a grant. The 31-year loan will attract an interest rate of 0.75 per cent with a grace period of six years.
Telemetry stations to monitor floods
In addition to infrastructure that curb floods, telemetry stations are being installed on identified flood hotspots across the country including mainly Kigali as a way of establishing early warning systems to reduce floods impact.
Telemetry is the automatic recording and transmission of data from remote or inaccessible sources to an IT system in a different location for monitoring and analysis.
The stations are expected to monitor the trends or peak flow of rivers, drainages and other flood hotspots as part of early warning systems aimed at minimizing the likely impacts of floods and plan for flood-resilient infrastructure.
Telemetry stations are real time sensors and can measure water levels instantaneously with an interval of 5 minutes, 15 minutes, or 30 minutes according to Remy Norbert Duhuze, The Water Monitoring and Quality Control Division Manager at Rwanda Water Resources Board.
So far 24 telemetry stations have been installed as the number is subject to increase in coming years.
"The flood hotspots have been identified and more telemetry stations will be installed to strengthen the early warning system. The telemetry stations are highly needed for the better management of water resources and to overcome some issues related to floods as well as improving water sharing through an appropriate water allocation,” he said.
Most of the stations, he said, have been installed in Sebeya river catchment, Mukungwa and Nyabarongo rivers catchment while other sensors have been installed on shared water bodies and Lakes.
The targeted new flood hotspots, he said, are located in Nyabugogo river catchment in City of Kigali and other telemetry stations will also be installed in Rwampara, Rwandex, Kinamba, Mulindi sub-catchments.