Hundreds of thousands of people are without reliable access to water across Africa because the wells drilled to supply them are falling into disrepair because they are not being maintained.

Every year thousands of boreholes and motorised hand pumps are put in place across the continent, either through national programmes or global aid agencies.

But while these offer short term relief, many are failing as a long term solution, according to the International Institute for Environment and Development.

The institute claims that hundreds of millions of dollars have been wasted on these projects because governments, donors and NGOs have built infrastructure but failed to recognise the need to maintain it.

It has drawn up a 30-point checklist of features that rural African water supply systems need to succeed.

They include the right technology, community ownership and local capacity to repair and maintain wells.

"The water community has often focused on building infrastructure, rather than on maintaining it. This failure is forcing women and children to carry water over great distances with serious impacts on their health and education," said the institute's Jamie Skinner.

"It is not enough to drill a well and walk away. Water projects needs to support long term maintenance needs and engage local communities. Without this, it is like throwing money down the drain."

The Institute based its recommendations on extensive research into the problem.

Of 52 deep water borehole and supply systems built by the charity Caritas since the 1980s in Senegal's Kaolack Region, only 33 still function today.

The Global Water Initiative has found that 58% of such water points in northern Ghana needed repair.

In western Niger, it found that of 43 boreholes, 13 are abandoned, 18 are non-functional for more than three days once a year, and 12 are non-functional for more than three days, more than three times a year.

"Across rural Africa, some 50,000 water supply points have failed, representing a waste of US$215-360 million," said Mr Skinner.

"It seems simple and obvious but it needs to be said: there is little point in drilling wells if there is no system to maintain them. Every day that a borehole does not provide safe water, people are obliged to drink from unclean pools and rivers, exposing them to water-borne diseases. "

Sam Bond