Sustainable watermanagement along Mlali River in Tanzania

The NWB Fund has approved a new project to improve the watermanagement of the Mlali River in Tanzania. It is part of a long term collaboration between partner organisations MORUWASA, Wami Ruvu Basin Water Board and World Waternet within the WaterWorx programme. This collaboration focuses on strengthening water security by improving drinking water availability and adressing the underlying causes of water problems. Like soil degradation and erosion that make the area more vulnerable for climate change.

Central issue is the strong dependancy of the city of Morogoro on the Mindu dam, that provides 70–75% of the drinking water. This source is under increasing pressure as a result of deforestation, ersoion and climate change. Tha capacity of the dam decreases and the availability of drinking water becomes less reliable.

Since 2017 the partners work together on strengthening the operational efforts of the waterutility and the local water management agencies. In the last few years this collaboration has been extended to an integrated approach. Not only the waterinfrastructure is improved, but also the management of the catchment. This watercycle approach presumes that sustainable drinking water availability is dependant on healthy ecosystems upstream.

From pilot to new step

During the last few years important steps have been made in the upstream component of the watercycle approach. Along the Ngerengere River, one of the five tributary rivers to the Mindu dam, a pilot was implented with agroforestry, tree nurseries and anti-erosion measures (financed by NWB Fund and Climate Adaptation Fund of WaterWorx). This pilot delivered valuable insights in what interventions work, both technically and socially.

Besides that, the impact of interventions was analysed with e.g. the FarmTree watershed reforestation tool, monitoring of waterquality and sedimentation, enhancing local cooperative organisations and networks. Together these activities form a solid base for catchment restoration.

The new project is around the Mlali River, another of the five rivers that feed the Mindu dam. This river is one of the most degraded in the catchment. The choice of this river is strategic: interventions are epected to have a big impact on wateravailability and sedimentation of the Mindu dam.

The project is a combination of naturebased measures and strengthening local collaboration. It includes agroforestry-systems and tree nurseries, but also analysis and monitoring of water and soil dynamics. Stronger local organisations will enhance local ownership and ensure continuation in the long run.

Towards structural financing and upschaling

An important aim of the project is building the businesscase for naturebased solutions. Systematically collecting data about costs, benefits end effects will lay the foundation for a broader investment programme for catchment restoration. The collected insights will be combined with reports form previous studies e.g. a market analysis of agroforestry products and a pre-feasability study on a waterfund. The ambition is to establish a waterfund as financing mechanism, where stakeholders that benefit from improved wateravailability and waterquality invest in the catchment.

The project along the Mlali River is an important step towards a structural approach of watersecurity in Morogoro. Practical experience, data and collboration together provide a scalable model and example for other areas in Tanzania and elsewhere. The contribution of the NWB Fund thus helps to integrate seperate pilots into in integrated and investable approach of watermanagement.