BACKGROUND

RIPWARIN was a five-year action-research project. The project was conducted to investigate water management in a water stressed catchment. Since the mid-1990s the Great Ruaha River, which is one of Tanzania's most important waterways (the catchment contains one of the countries main rice growing areas, 50% of the countries installed hydropower capacity, as well as an important National Park and wetlands), has ceased flowing in the dry season every year. This has occurred because water levels in a large wetland, located on the Usangu Plain (close to the headwaters of the river) have dropped below a critical level and dry season outflows from the wetland have ceased

The research questions

• What flow is required downstream of the wetland and how much water needs to flow into the wetland to maintain this flow?
• What management interventions (both technical and non-technical) could be used to improve downstream flows?
• Is local irrigation efficiency an important factor and could it be improved to liberate sufficient water for downstream uses?
• What role should economic valuation of different water uses play in determining water allocation in the catchment?
• Is the recently introduced formal water rights and fees system an effective mechanism for water management?
• How are different types of decision support system best used to improve water management and the decision-making process?

Hypothesis tested/Investigated

In a catchment, in which agriculture is the principal anthropogenic use of raw water, sufficient improvements in irrigation efficiency and productivity can be found to provide adequate water for other sectors and downstream needs.

Objective

The primary objective of the project was to enhance understanding of water competition, management and productivity in the catchment and to determine how the Government of Tanzania could keep its promise (made at the Rio+10 preparatory meeting in London, 2001) to return the Great Ruaha River to year round flow by 2010.

Method

The project was implemented by 3 organizations: the Soil Water Management Research Group, University of Sokoine, Tanzania; the Overseas Development Group, University of East Anglia, UK and IWMI. The project was multi-disciplinary, investigating technical, economic, institutional and social aspects of water use and management. Much of the research was conducted by five Research Assistants conducting PhDs, jointly supervised by staff from the 3 institutions. These studies comprised: i) assessment of irrigation efficiency and productivity, ii) hydrological and environmental analysis, iii) economics and livelihood analysis, iv) assessment of the effectiveness of water rights and fees; v) development of a decision support system. We collaborated closely with other key institutions in the area, most notably the Basin Water Office, which is responsible for managing water in the catchment.

Project leaderS

i. Bruce Lankford, University of East Anglia, UK  (b.lankford@uea.ac.uk) (www.uea.ac.uk/dev)

ii. Henry Mahoo, Sokoine University of Agriculture, Tanzania (hmahoo10@yahoo.co.uk)

iii. Matthew McCartney, IWMI (m.mccartney@cgiar.org)

IWMI Researchers

Major Donors

Project Duration