All along our Andes, that shape our mountain range, we are able to appreciate a series of reservoirs that for their denominated high Aldean location, of the medium capacity that they have had for the function of storing rain water.  We are able to appreciate capacities ranging from hundreds of thousands cubic meters to nearly a million cubic meters, never positioned in the river beds, not as we see now, located on the baseline of the river, reservoirs of great capacity (Blind Man’s Bluff) that through the process of basin erosion itself has sealed itself off and presently operates with a capacity of nearly 50%.

As Technical Administration of Irrigation in the Basins of Nepeña, Casma, and Huarmay, we went inch by inch over the birth of the basins, and we rediscovered water reservoirs of medium capacity, which were utilized to retain water during times of rainy seasons and redistribute them in months of low water level, covering its hydraulic needs wisely.

As an example of the hundreds of reservoirs that exist in all of our mountain ranges and of the way that water use was planned, we point out Ricococha, located in the district of Pamparomas, province of Huylas, inside the basin of the Nepeña River, Ancash, at an altitude of 4,450 meters above sea level.

This Pre-Inca reservoir has a holding capacity of approximately 0.1 million m3, all of the walls built with rock and earth, probably with an agglomerate of material that should be investigated.  Height of the dam 4 meters, width of the top wall 1.5 meters, width of the bottom of the wall 4 meters and longitude approximately 150 meters.

In the center of the dam ventilation nozzles are located, that are windows and were plugs during the rainy period.  These can be found at different levels, and this is how discharge was controlled.  To gain access to the nozzles, on the wet side, they had a stairway system that projected out from the body of the reservoir.

These dams show the marvelous hydraulic engineering, the good knowledge of the basins, that were utilized many centuries before the Tahuantinsuyo Empire will be formed.  It is necessary to rescue and reutilize such wise experience that still has not been overcome by science and technology today.

Simulated operation of the reservoir Ricococha