The European Space Agency helps South Africa share water fairly

On World Water Day, how can the government achieve the sustainable use of water for the benefit of all South Africans?

ESA has been working in partnership with two Dutch companies and a South African catchment management authority to find a solution. Some 20 year ago, in response to severe water shortages, the South African government passed the National Water Act, which is intended to restrict the amount of water farmers use for irrigation.

Maurits Voogt, who works for HydroLogic, a relatively small company based in Amersfoort in the Netherlands, says: “It is a major task to monitor and enforce the legal use of water in places where there are limited qualified personnel available, and the areas that need to be monitored are huge. “We have developed a smart, satellite-based water auditing service as part of ESA’s programme of Advanced Research in Telecommunications Systems (ARTES). It allows water management authorities to monitor irrigated water use in large areas without actually needing to visit every single farm.

“By doing so, the water auditing application helps them implement regulatory measures effectively, and thereby supports the sustainable use of water resource.”

The water auditing service uses evapotranspiration data calculated from satellite imagery by partner company eLEAF, based in Wageningen. Combined with rainfall data from rain gauges and satellites, this evapotranspiration data is used to calculate how much water is used for irrigation. The application automatically compares the water use with data taken from a national water use register that lists the amount of water allocated to each farm.

Vincent Chappard

Vincent Chappard

Vincent is an aerospace editor and consultant based in Paris.