Experts weigh in on how deadly floods, landslides can be prevented

A proper drainage system, rainwater harvesting, and soil erosion control measures, can go a long way in preventing and mitigating floods and landslides in Rwanda, experts have said.

Friday, May 20, 2016
Gakenke residents remove mud from a road after heavy rains that left the road impassable. (Teddy Kamanzi)

A proper drainage system, rainwater harvesting, and soil erosion control measures, can go a long way in preventing and mitigating floods and landslides in Rwanda, experts have said.

The advice comes in the wake of deadly landslides and floods that have devastated parts of the country. 

Such measures, experts say, could have averted the deadly floods and landslides that particularly hit Gakenke, Muhanga, Rubavu and Ngororero districts earlier this month, killing as many as 49 people.

An assessment exercise established that the May 7 and 8 disasters saw Gakenke lose 34 people alone, Muhanga 8, Rubavu 4, and Ngororero 3; while dozens of cattle were also killed, over 500 houses destroyed, several hectares of farms ravaged, roads and bridges damaged, among other destroyed properties.

The assessment, jointly done by officials from the Ministry of Disaster Management and Refugee Affairs (MIDMAR), the Ministry of Local Government and Social Affairs, Ministry of Natural Resources, Rwanda Housing Authority and Rwanda Defence Forces (RDF), also aimed at identifying risk-prone areas, and informing recovery efforts and future actions.

Earlier, the Rwanda Meteorology Agency had warned of potential landslides, warning especially people living on hillsides around the country.

Eng. Omar Munyaneza, a researcher in hydrology, climate change and water resources management, told The New Times that when it rains heavily and rainwater flows on bare surface it often causes nearby water bodies to overflow, and flooding.

Munyaneza, a lecturer at the School of Engineering at the University of Rwanda’s College of Science and Technology, said people most prone to such disasters are those living in hilly areas or wetlands.

He made reference to a study carried out in 2015 on the flood management in Nyabugogo, a Kigali suburb, which he said established that only 25 per cent of rainwater in the capital is absorbed in soil, while 75 per cent flows to various places.

He said, at this rate, the study projected that, in 30 years, the run-off coefficient will be 95 per cent, if nothing is done to reverse the trend.

Munyaneza said every building that’s constructed should be able to retain and harvest rainwater, such as through a tank.

He also called for the setting up across the country of such water dams as the one in Rugeramigozi, Muhanga District, so that when it rains water can get collected and used for irrigation during the dry seasons.

"We need water for various development activities, but because we aren’t able to manage it property, it ends up causing destructive floods instead,” Dr Munyaneza said.

According to figures from MIDMAR, from January up to May 9, over 80 people had been killed in rains, while 74 others were injured. Some 898 houses were also destroyed, while over 1,500 hectares of crops were damaged over the same period.

Last year, heavy rains killed 94 people in the country, injured 122 others, killed 93 domestic animals, and damaged 1,670 houses as well as 2,178 hectares of crops.

Jean Baptiste Nsengiyumva, the director of the risk reduction and preparedness unit at MIDIMAR, said that Gakenke in the Northern Province and Ngororero in the Southern Province are among the most disaster-prone areas.

"We are on high alert because we have realised that if it continues to rain, these areas could even experience more challenges,” he said.

He also said all the rivers and marshlands in the Eastern Province had flooded around the same time as a result of heavy rains.

Nsengiyumva said the most urgent action is the relocation of people living in high risk zones, a decision he said had been taken five years ago.

Last month, MIDMAR said Rwf4 billion had been put aside for the relocation of residents in the high risk zones, although it was deemed insufficient.

Taking weather warnings seriously

Reuben Ahimbisibwe, the director-general of infrastructure in the City of Kigali, said there is a project in the offing that will help address issues related to water management, housing, and transport.

He said the project, estimated to cost between Rwf17 billion and Rwf18 billion, was designed by Italian experts.

He said the objective is to widen water drainage channels, including Mpazi, as well as the Nyabugogo River along its 600 metres to ease its water flow. Another aspect will be to relocate people from wetlands.

Ahimbisibwe explained that, in the transport sector, the project will help widen the Nyabugogo-Poids Lourd Road, while a ring road in the area will also be constructed.

But the city is still mobilising funds for the project, the official added.

Experts also spoke of an urgent need for another road that connects Kigali to Gatuna, warning that if heavy rains continued there was a high chance of Nyabugogo Bridge getting significantly damaged.

The Government has announced plans for an alternative route but not before next year.

The Minister for Disaster Management and Refugee Affairs, Seraphine Mukantabana, said recently that plans were underway to construct a new tarmac road between Gisozi and Karuruma as another exit route from the capital to the Gatuna border.

Construction works are set to begin in February 2017, she said.

Dr Munyaneza also advised that any development project being undertaken should consider a hydrological study, pointing at the need to raise the Nyabarongo Bridge as it can easily get submerged when it rains heavily.

Meanwhile, Nsengiyumva said there is need for the general public to take heed of weather warnings from the meteorology agency, if efforts to prevent and mitigate disasters are to succeed.

"Rain does not surprise us. But, more often than not, when people receive prior warnings from the meteorology agency, they dismiss it; there is a tendency of people not believing in weather forecasts,” he said, urging the public to change their attitude.

Anthony Twahirwa, the head of weather/climate services and applications at the Rwanda Meteorology Agency, said that indeed people tend to ignore their warnings. 

He also faulted media houses that do not help publicize the agency’s weather forecasts.

"Some simply do not want to disseminate the information unless we pay them for it; I believe that’s in breach of their social responsibility. Such information is intended to save the lives of the people and should be given priority,” he said.

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