According to the political-administrative division, is located in the San Francisco district of the canton of Guarco, both in the province of Cartago.

Based on geographic location and mapping can locate the sub-basin of the River Sombrero using the geographical coordinates of the projection spheroid Clarke, d Activity of 9 º 44 `15 `` to 9 º 47` 32 `` N and 83 º 53 `03 `` 55 `` to 83 º 38 west longitude, and within the map coordinates, Lambert grid, 544000 to 550000 on the horizontal axis and 191000 a1980 on the vertical axis.

It comprises an area of 6,400 hectares and was established by Executive Order No. 15436-MAG of 30 March 1984, published in the Gazette of June 5, 1984 ..

 

Life Zones

 

In the flat sections and depressions develop deep soils with textures, sandy clay loam. Brenes referring to Unit III Talamanca, which owns the Hat River sub-basin, described as clayey soils in the lower parts and a stony, shallow and varied texture on steep slopes.

The researchers collected data Villalobos Ortiz to calculate the annual rainfall in Hat River subbasin, based on information supplied by stations pluviographs The Doll, Bethlehem and El Llano.

None of these stations is located directly in this sub-basin, which is why, to determine the average annual precipitation was estimated by the method of Thiessen polygons, resulting 2675.30 mm per year.