/ 16 March 2011

Plumbing grey data for clear water

They come like pilgrims to the department of geological surveys office in Lobatse, 120km south of the Botswana capital. In the sparsely furnished offices there, they pore over charts, trying to take the guesswork out of choosing where to sink a borehole.

Success means cool clear water welling up from the earth to supply a farm or a village. Failure means thousands of pula wasted, a failing business or continued hardship for a community.

Johannes Tsimako, of the geological surveys department of the ministry of water, minerals and energy affairs, sees farmers who have travelled long distances to access the data in his office.

The alternative is to hire an expensive independent surveyor, with no guarantee of success.

Keinetse Keineetse is a farmer at Phiriyabokwete Lands, just 80km from Gaborone.

Keineetse, a retired media personality who has turned to raising livestock, paid dearly for failed attempts to locate water on his farm.

He attributed the failure to lack of detailed information as to where to find the water around his farm. “I hired a surveyor who charged me $450 and he identified a place where I drilled a hundred metres at a charge of $39 per metre but I hit a blank,” he said.

“I still had to pay.”

The data held at Lobatse is meant to guide surveyors, but it is sadly partial. The vital information is not easy to come by; much of it is held at institutions outside the country, and ordering copies is costly.

But a knowledge-sharing project that aims to fill in many of the gaps in the hydrogeological image — the map of underground water — in Botswana and the rest of Southern Africa was launched in January 2010. Supported by GIZ, the German Development Cooperation agency, at least 2 000 “grey items” will be rescued from various places and made available to surveyors via the internet by the middle of 2011.

Jude Cobbing, a hydrologist at Water Geosciences, a consulting company, explained to IPS that a grey item is an unpublished report or paper — or one that was only published in limited quantities and is now out of print.

“Essentially, grey items are reports or research papers that are difficult to get hold of,” he said.

A huge body of knowledge containing all sorts of data for Africa –ranging from water levels and rainfall to discussions of groundwater sustainability and climate variations — is currently in the category of grey data.

“Grey reports can provide us with a picture of past water use and/or climate which is hard to get elsewhere,” Cobbing said.

He said that many of these unpublished or limited edition reports are held outside of Africa, at institutions such as the British Geological Survey, but other data is stored on the continent. “And this is why we would like to partner with African organisations.” As the data is recovered and organised, it will be made available via a web portal that anyone can access.

Keineetse eventually found water on his farm, after turning to another surveyor, this time someone with a strong reputation for success earned with good work for the water affairs ministry.

He found water, but it cost him over $10 000 to drill, $6 000 more to equip the well with solar panels for a pump, and another $450 for the surveyor’s work.

“I used the family funds that were saved for the children,” Keineetse said.

“The portal will be huge relief in that it will remove the uncertainty for many farmers and reduce chances of lost resources because if you hit a blank due to lack of knowledge you still have to pay lots of money.”

The new data resource will not actually help someone like Keineetse directly with locating underground water.
“Grey data can help broadly identify areas where groundwater may occur due to the underlying geology, but can’t help find groundwater consistently or reliably in your backyard or farm,” says Rex Brown, an environmental scientist based in Swaziland, before raising an interesting question.

“If we can find oil thousands of metres below groundwater, why can’t we find water tens or hundreds of metres below ground?”

The geological surveys department’s Tsimako said that there are currently outreach programmes to support farmers searching for water, but these are not systematic or convenient.

“The portal will be more important for farmers to access the information wherever they are and whenever they need it instead of travelling all the way for such information,” he said.

Brown argues that the techniques and equipment used to locate groundwater have barely advanced in the past 60 or 70 years.
“Water exploration must tie itself to the advances made in the petroleum industry whereby specialist software and computers can help remove errors or false readings.” — Sapa-IPS