How are dams operated in Summer?

Here we bring you very valuable information on the operation of dams to help you understand why their appearance is different at times.

What is a dam?

It is a work of engineering for the accumulation of water,  which is the product of the construction of a dam in the basin of one or several rivers.

What are its functions?

Controlling the river flow always protecting the lives of the people, material assets and the environment; generating water impoundments for human consumption, agriculture and livestock; generating energy and providing spaces for the development of tourist activities, sport and recreation.

How are dams managed?

The dams lead to the realization of a series of operation and maintenance tasks such as water level regulation through flow control valves or gates, according to a study based on a series of variables like rainfall, catchment basin, type of rivers, infiltration of soils, evaporation, importance and typology of the dam, spillway systems, storage capacity and season, etc.

What is the dam head?

The water head is the reference point used for measuring the dams water level. The terms “above head” or “below head” indicate how many centimeters are these levels above or below that point of reference.

Why do the dam heads tend to be lower during summer?

With the values mentioned above, the dam water head is determined in accordance with the expected behaviour for the different seasons, always bearing in mind the safety of people and the dam. This, without disregarding the water requirements to meet the necessity for human consumption and various water uses in the province.

The dam-below-head operation responds to a programmed action taking into account that, in this geographical area of the country, the highest rainfall occurs in summer (from September to March). It is expected that, during this period, reservoirs are operated in a controlled manner, keeping their head below normal level in order to be able to have a larger capacity to withstand flash floods typical of the season.

By the end of the summer season, the dams are kept at their highest head, so as to collect sufficient water to face the coming seasons of low or zero rainfall. The intervention framework described above refers to a generalization of the dams operation, as every dam has its own characteristics that make its management different in each case.

Regarding dams, San Luis presents a unique reality in the country, being one of the states with the greatest number of reservoirs. Currently, the province reaches a total of 20 dams strategically distributed in its territory. San Luis Agua is responsible for operating and maintaining each of the 20 dams in San Luis, a task performed through the department of Dams, Reservoirs, and Rivers.

For more information, contact the San Luis Agua Dams Department, through Autopista de la Información phone line 59-0266-4452000 Ext. 4873, or by e-mail: In addition, visit our page and stay updated through our social networks.