Last week, the water rose so quickly in Jangwani that residents had little warning before they had to flee their homes. As heavy rains filled the Msimbazi River, which cuts through this low-lying, unplanned settlement in central Dar Es Salaam, water backed up against a recently constructed bridge, breached a makeshift barrier of mud and trash, and poured into the settlement.

The Dar Ramani Huria team visited Jangwani today to survey the damage. The neighborhood lies within Magomeni ward, which is one of 17 flood-prone wards of the city that the project is focusing on.

Flood affected area CREDIT: Ramani Huria

Flood affected area CREDIT: Ramani Huria

Luckily, everyone in the area was able to escape to higher ground as the flood raged through, but locals told us that about 200 homes were damaged or destroyed, affecting hundreds of people. Some local residents have found shelter in a nearby bus station, sleeping with their young children on foam mats. They said they had abandoned their homes for fear of more flooding.

Residents seek refuge from flooding CREDIT: Ramani Huria

Residents seek refuge from flooding CREDIT: Ramani Huria

Heavy rains have been falling for the past two weeks across Dar, causing severe localized floods. The rains come regularly during the wet season, but this year’s floods have been the worst in recent memory. Locals were shocked at the torrent that came through Jangwani. On the walls of a nearby bus terminal mud stains mark the high water level, more than a meter off the ground.

Several residents of Jangwani spoke about how disruptive the floods have been to their livelihoods and also pointed out the damage that the flooding was doing to the city’s infrastructure. The bus terminal, which is still under construction, clearly lies in the path of floods.

“It’s such a waste,” said one man, shaking his head.

Seeing the human impact of flooding made the project’s goals all the more real for the team and brought home the impact that open data could have.

By creating accurate and easily updatable maps of areas like Jangwani, the project will enable better disaster planning and response using InaSAFE, a software that allows decision makers to run realistic flood and disaster scenarios. The insights gleaned from this open data won’t only save the city millions of dollars every year, it will save homes and lives.

Flooding in Jangwani CREDIT: Ramani Huria

Flooding in Jangwani CREDIT: Ramani Huria

The residents of Jangwani are eager for solutions, but the memories of such disasters can fade quickly, leading to poor planning and decision making (at all levels) in the future. Through Dar Ramani Huria, the residents Jangwani themselves will work to collect data and map important features of their communities, including drainage and floodplains, in OpenStreetMap. Beyond being an effective way to collect large amounts of accurate data, this community based effort also brings the realities of disaster planning and risk reduction to the local level, helping to ensure that the disasters that hit communities like Jangwani each rainy season don’t continue.