Introduction

Dar es Salaam obtains most of its water from the Ruvu River through two main schemes (Upper and Lower Ruvu) and also from a small surface water scheme (Mtoni). Boreholes fitted with electric or hand pumps have recently been developed in the city to alleviate the effect of shortages (when the water level in the Ruvu river is just sufficient to supply intakes); but the safe yield of the aquifer is unknown and quality of the water is doubtful. Based on the recently published household Budget Survey (2000/2001), around 85% of city's population has some kind of access to piped water supply.

However the is service erratic with most households getting it less than six hours per day. Over 45% of the households buy water from neighbours, tanker trucks or from groundwater, is likely to be sufficient to supply a city of 3.0 million, a population Dar es Salaam is likely to reach in 2007.

The Upper Ruvu treatment plant (82,000 m3/day) was rehabilitated in the mid-1980s. The Lower Ruvu treatment plant (182,000 m3/day), built in the mid 1970s, is practically out of order and water produced is in fact not adequately treated. On a fraction of the total production of the two Ruvu schemes reaches the city because of off-takes on the two 50km transmission lines, often illegal and/or for irrigation purpose.

The transmission lines have many weak points and can burst anytime; the 1999 and 2002 floods washed away sections of the Lower Ruvu transmission mains and created water shortages for over a million people for almost 10 days. The primary distribution network is sufficiently developed, but because of poor balancing and limited coverage of secondary distribution, many neighbourhoods have to rely on long-and sometimes unofficial - individual connections. Poor piped water service has encouraged very active water vending "industry" and the development of the above-mentioned boreholes. Overall management of Dar es Salaam main source of water (the Ruvu/Wami river basin) needs to be strengthened.

Several options for Dar es Salaam future raw water source have been identified, but no decision can be made before an independent regional environmental impact assessment is carried out. Once a decision is made there will be a need to thoroughly prepare a program to extend water storage, production, transmission and main distribution to meet a demand expected to be multiplied by 1.5 before 2015.

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