| Groundwater Basin Facts The sediment in the valley is several thousand feet thick. These sediments vary in their ability to transmit water. Units that transmit water poorly are called aquitards or confining units. Units that transmit water well are called aquifers. Groups of aquifers and aquitards are called "aquifer systems" or "groundwater systems." Most of the wells in the Las Vegas area draw water from the confined aquifer system, which is several hundred feet thick. Because this is the most important part of the aquifer system, it's sometimes called the "principal" aquifer. This aquifer system is confined by an aquitard, which is about 200 feet. Water within the upper 30 feet of this aquitard comes from landscape irrigation and is very salty. This upper 30 feet of sediment is called the shallow zone or shallow system. Because this salty water is close to the land surface, it can dissolve foundations and be a problem for construction excavations. Although this water is not a good source of drinking water, the Southern Nevada Water Authority and private parties are researching methods to extract, treat and use this water. |
All
groundwater in the Las Vegas Valley comes from the mountain ranges surrounding
the valley. Rain and snow seeps into the ground and may travel for thousands
of years before reaching the center of the valley.