Info

CLM has considerable water resources. The annual average precipitation oscillates between 300 and 600 mm. The volume of the average annual precipitation constitutes 41,000 hm3, which is equivalent to an average isoyet line of 510 mm (IGME, 1985). As a result of evapotranspiration, and water exchange to and from neighboring regions, the total available water resources, on average in CLM, approximate 9,258 hm3 year-1.

The distribution of resources in the region is not uniform. In the Tajo river basin, which occupies a third of the regional territory, 46.5% of the resources are concentrated, whereas in the Guadiana, which is comparable in surface area, only 19.6% of the total is found. In terms of the total water run-off in CLM, 67% remains surface water and the 33% remainder circulates subterraneously, giving insight into the importance of groundwater sources.

Among the existing geologic formations in CLM, practically only the limestone, dolomites, sands, gravels and clays can contain groundwater in sufficient amounts to constitute aquifers of interest at the regional level. These are located in geologic units from the Mesozoic, Jurassic and Cretaceous (CES, 2006).

The natural water contributions are distributed in a non-concordant form in time and with demand patterns. In order to achieve balance between water that is available and demand, it is necessary to have adequate regulation. For this reason, the construction of reservoirs for storing surface water and the sustainable management of groundwater resources is necessary (Table 2).

Table 2: Storage capacity and regulated resources in Castilla-La Mancha (CES, 2006)

River Basin

Storage Capacity (hm3 year-1)

Regulated resources (renewable) (hm3 year-1)

Superficial

Groundwater

Superficial

Groundwater

Total

Tajo

3,395

15,000

1,643

1,108

2,751

JĂșcar

2,016

23,000

0 0

Post a comment