unconfined

The major aquifers in Texas include the Ogalalla aquifer, the Gulf Coast aquifer, the Edwards aquifer, Carrizo-Wilcox aquifer, Edwards-Trinity (Plateau) aquifer, the Seymour aquifer, the Hueco-Mesilla Bolson, and the Cenozoic Pecos aquifer.

Ogallala aquifer

Aquifers are an important source of water for humans, supplying about 60% of the water we use. Most of the water pumped from aquifers goes to agriculture to irrigate food crops. Over 80% of the irrigation water used in Texas comes from one aquifer, the Ogallala. The groundwater in some aquifers can be ancient.

Major Aquifers

• Pecos Valley.
• Seymour.
• Gulf Coast.
• Carrizo-Wilcox.
• Hueco-Mesilla Bolsons.
• Ogallala.
• Edwards-Trinity (Plateau)
• Edwards (Balcones Fault Zone)

Ogallala Aquifer

Groundwater in Texas is governed by the legal doctrine known as the Rule of Capture. Under the Rule of Capture, a landowner needs no permit to drill a well and pump groundwater, and he may pump as much water as he may beneficially use even if that causes his neighbor’s well to go dry.

between 50 and 800 feet

9 major aquifers

Ogallala

Groundwater is the major source of drinking water in most rural areas and especially in San Antonio and Lubbock.

Groundwater use is highest in parts of the country with limited rainfall but high water needs, especially for irrigation….Which areas in the United States are most dependent on groundwater?

If the aquifer goes dry, more than $20 billion worth of food and fiber will vanish from the world’s markets. And scientists say it will take natural processes 6,000 years to refill the reservoir.

Because of widespread irrigation, farming accounts for 94% of groundwater use — and use of the Ogallala. Irrigated ag forms the base of the regional economy, actually supporting nearly one-fifth of the wheat, corn, cotton, and cattle produced in the U.S.

The true threat is posed by agriculture as it’s currently practiced on the Great Plains by the farmers themselves, many of whom opposed the pipeline vehemently. The aquifer is being wasted and polluted. Wasted, that is, on corn, a thirsty crop that requires over 20 inches of irrigation water in parts of the Plains.

1200 ft.

Within 50 years, the entire aquifer is expected be 70% depleted. Some observers blame this situation on periodic drought. Others point to farmers, since irrigation accounts for 90% of Ogallala groundwater withdrawals.

The Ogallala-High Plains Aquifer is one of the world’s largest groundwater sources, extending from South Dakota down through the Texas Panhandle across portions of eight states. Within 50 years, the entire aquifer is expected be 70% depleted. Some observers blame this situation on periodic drought.

An aquifer is an underground layer of water-bearing permeable rock, rock fractures or unconsolidated materials (gravel, sand, or silt). Groundwater from aquifers can be extracted using a water well. The study of water flow in aquifers and the characterization of aquifers is called hydrogeology.

The Ogallala Aquifer has long been unable to keep up with these agricultural demands, as the aquifer recharges far slower than water is withdrawn. At the state level, the focus has been on maintaining an orderly depletion of the aquifer rather than developing a plan for sustainable use.

If the aquifer is shallow enough and permeable enough to allow water to move through it at a rapid-enough rate, then people can drill wells into it and withdraw water. Excessive pumping can lower the water table so much that the wells no longer supply water—they can “go dry.”

Using less water can help save the Ogallala Aquifer. At the current rate of use, part of the Ogallala could be exhausted within this century and may take 6,000 years to restore. It is important to develop agricultural innovations to area farmers sustain agricultural production in that region.

Aquifers may be artificially recharged in two main ways: One way is to spread water over the land in pits, furrows, or ditches, or to erect small dams in stream channels to detain and deflect surface runoff, thereby allowing it to infiltrate to the aquifer; the other way is to construct recharge wells and inject water …

A well is said to have gone dry when water levels drop below a pump intake. This does not mean that a dry well will never have water in it again, as the water level may come back through time as recharge increases.

Depending on its permeability, aquifers can gain water at a rate of 50 feet per year to 50 inches per century. They have both recharge and discharge zones. A recharge zone usually occurs at a high elevation where rain, snowmelt, lake or river water seeps into the ground to replenish the aquifer.

As Steward and his colleagues found, farmers would have to cut their groundwater pumping by 80 percent today — to bring depletions in line with rainwater recharge.

Plant more trees of local varieties or restore the denuded patches of natural forest. Stop indiscriminate drawing out of ground water through bore wells. Build check dams across rivers to retain more water in the river bed after the rainy season. Encourage farmers to dig pits in the farms to hold rain water.