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COLOMBIA
The landscape of Valle del Cauca is dominated by sugar
cane. The department, which is located on the edge of the
Pacific Ocean, is one of the most important in Colombia.
Sugar cane needs water. A lot of water. With the Cauca River
and its numerous tributaries in the area, that should not
be a problem. However, rainfall in the area can fluctuate
dramatically and so water supplies are unstable. In
addition, El Niño and La Niña accentuate this effect.
If there is not enough water from the rivers, local farmers
pump up groundwater. And because they have to resort
to this more and more often, the water table is falling and
there is a risk of wells drying up. In addition, large numbers
of applications are received for digging new wells: permit
applications come in for a monthly average of between ten
and fifteen wells.
But how responsible is it to issue the permits? Will that not
destroy the balance of the groundwater system? The local
water management agency, the Corporación Autónoma
Regional del Valle del Cauca (CVC), does not wish to
interfere with economic activity, but nor does it want the
groundwater system to be damaged irreparably.
Deltares is now working for CVC, mapping out the regional
groundwater system and making calculations to assess the
impact of climatological changes on groundwater stocks.
These data will be used to set up an operational system.
On that basis, CVC will be able to make targeted decisions
during periods of drought about where new wells can be dug
and howmuch groundwater can be extracted. In that way,
economic growth and the protection of the natural system
can be combined.