Rain water harvesting improves lives of Tanzanian farmers

In recent years, residents of Tanzania's Kilimanjaro region have seen their livelihoods threatened by climate change-induced water shortages.

The Kilimanjaro region has always been one of the driest in Tanzania, receiving less than 400 mm of rainfall annually. The average annual rainfall for the country is 900-1000 mm.


  • In one of Tanzania's driest regions, UNDP has supported a local NGO in constructing dams that store up to 220,000 litres of rain water.
  • Improved water supplies have allowed farmers to feed their families and earn extra income from produce sales.
  • In 2004 UNDP launched the Community Water Initiative (CWI) to foster carbon-neutral water security in Tanzania and nine other countries.

Recently, however, changing rain patterns have exacerbated the already dry conditions as the traditionally rainy months of October and November brought no steady showers.

"If there's a bad year, we can stay up to 20 days without rain. The young crops die, that's the problem over here", says Rabiet E. Mkumbwa, 60, in front of his home in Mwembe village.

In addition to crop failures, drought conditions have caused soil erosion, thereby reducing soil fertility and crop yield. 

To help area residents continue to farm their land, feed their families and earn an income under such conditions, UNDP has supported a local NGO - the Same Agricultural Improvement Project (SAIPRO) - in constructing micro-dams. These dams, which are based on the concept of traditional, local water reservoirs known as "ndiva," are large pools that collect water as it streams down the hillsides.

The dam in Mwembe village can store up to 220,000 litres of rain water. It is owned and maintained by a group of community members, including 20 women and 30 men, who clean the mud out from the pools and manage the distribution of the water.

Once a week, they open the dam’s valve and manually channel water to the community’s farm plots, which cover 200 acres of farmland and serve up to 150 households.

To improve the flow of the water and maximize its reach, villagers are also encouraged to build canals that connect the dam to their plots.

“By collecting small contributions you can buy cement and do the construction in phases,” says Stella Zaarh, from UNDP Tanzania’s GEF Small Grants Programme.  

The successful dam project in the Kilimanjaro region has strongly impacted local communities.

With improved water supply to their plots, local small-scale farmers are able to not only feed their families better, but also earn extra income from selling their produce at local markets. With this income they can send their children to school, raise poultry and cattle, and make improvements to their houses, such as replacing hay roofs with iron sheeting.