Groundwater monitoring plan in the province of San Luis

The province of San Luis has an extension of 7.700.000 ha and has 1,200 registered drillings (Figure 1), of which 40% are destined for agricultural use, being the central pivot irrigation the most used system between producers. The other 60% belongs to drillings used for livestock and to a lesser extent human consumption and industrial use.

Most of the perforations are distributed in 5 hydro geological basins: Llanura Norte, Conlara, Río Quinto, Bebedero Este y Llanura Sur. Llanura Norte basin has an extension of 4,976 km² and is located in the north of the province; it runs from the town of San Francisco del Monte de Oro to Los Cajones place and from the occidental foothills of San Luis mountains to Pampas de la Salina. One third of the 480 agricultural drillings are located on Llanura Norte Basin, due in great part, to the advance of productive boundaries, the strategic location of the region, the availability of highly productive soils and a broad and sustainable water offer, added to a high investment in energy and road infrastructure works.

In accordance with the 2012–2025 Water Master Plan, San Luis Agua S.E. has started an integrated management of the provincial water resources, developing investigation projects destined to the implementation of technology for the strategic planning of the resources. By virtue of a larger demand from the productive sector of information about specific data such as availability and quality of water in the province, San Luis Agua launched the monitoring project, which obtains data from 150 spots strategically located.

In each of them, studies of water quality are made (pH, salinity, dissolved oxygen, temperature), accompanied by pumping essays, drillings hydraulics tests, level measurement, performed with seasonal periodicity to know the state of the aquifers’ level of exploitation. Since 2013, and with the participation of productive sector, investors and users, San Luis Agua S.E. carries on a Telemetric Monitoring Plan in real time through the installation of 59 stations, located near the town of Quines. This first stage, developed in Llanura Norte basin, includes the reload zones located in the Central Mountains of San Luis. The final project will have the measurement of hydro meteorological parameters in real time tending to the making of an Integral Hydric Balance, designed for the needs of users and planning.

Data provided by the Stations With real time information (Figure 2), the local productive sector is provided with precipitation rates (historical, accrued, partial), ambient temperature (max, min, average), soil humidity, wind speed and direction, solar radiation, aquifers hydrodynamics; all useful data for an efficient use of water, predicting critical stages of production, minimizing economical losses and rising profits.

Knowing the natural water distribution in all the hydrological systems: groundwater, superficial, to improve the operation of dams, canals, aqueducts, to the effects of rising efficiency in the use of water. Also serves for evaluating the expansion of distribution. Controlling and avoiding over exploitation of resources, generating water balances and evaluation of the offer.

The plan is developed in operational phases that include the installation of auto linked remote stations provided with sensors (Figure 3). These stations will use radio, satellite and gprs connectivity, according to the case. The data collected will be reported to a master station, located in the offices of San Luis Agua, which will be used as a link of communication with the information highway, ensuring the availability of information through a specially designed web service.