As part of a new project aimed at helping communities adapt to recurrent flooding, the Cameroonian government is installing rainwater harvesting systems in vulnerable Douala neighborhoods. The idea is simple: Catch and store clean water for people to use whenever flooding makes groundwater unsafe.
After the floods in June, the government put $185 million into Douala’s Urban Development Programme for the Emergency Rehabilitation and Construction of Infrastructure fund. Along with improving drainage systems and rehabilitating road networks, the money is going into the first phase of the rainwater harvesting project, which is due to be completed at the end of this year.
According to Benoit Som, one of the deputy mayors of the Douala V council, 15 squatter settlements in Douala will get two rain harvesting systems each, at a cost of 1.3 million fcfa ($2,500) per system. Each system includes tanks installed outside houses with corrugated iron roofs.
During the rainy season, rainwater flows down the roofs and into the tanks. In some cases, water is also stored in larger iron and concrete water storage tanks, which have a capacity of around 80,000 liters. The collected water is then treated and connected to a plumbing system to be used by the households near the tank.
According to health experts, 60 percent of Douala’s population of 3 million depends on water from wells, many built close to pit latrines. When the area floods, sewage can get washed into the community’s water supply. The number of cholera cases in the city jumps from less than 50 per week to over 400 during rainy seasons that involve flooding. Council officials believe the rainwater harvesting project can help cut those numbers in the future.
“The project will help strengthen the adaptive capacity of the beneficiary communities, reduce the risks faced from the effects of climate change like floods, and in turn influence the policy to promote sustainable management of water resources,” Augustine Njamshi, executive director of the Bio-Resource and Development Centre in Cameroon, said.
“A big city like Douala needs alternative sources of potable water, and rainwater harvesting is one of those cost-effective and environmentally friendly sources,” said Tchepnang Barthelemy, coordinator of the Centre for Assistance to Justice and Animation for Development, a nongovernmental organization in Limbe.
Rainwater harvesting can cut the need to build other expensive water-supply systems and create the ability to farm or build in areas with no other access to water, he said, as well as making floods less destructive by capturing more water. For the residents of Douala, however, what is most important is that they can have access to clean water when they need it.
“Women and children sometimes spend up to eight hours per day searching for portable water,” said Marie Noel Ebang, a shop attendant in Makepe, which recently got two rain harvesting systems. “This rainwater storage device has improved access to safe drinking water and decreased the time needed for water collection.”