Water to the north of the Canadian River is generally fresh, with total dissolved solids typically less than milligrams per liter. However, water quality diminishes to the south, where large areas contain total dissolved solids in excess of 1, milligrams per liter.
Increased salinity may be associated with evaporative concentration of groundwater in saline playa lakes in the southern portion of the aquifer, up flow of more saline groundwater from the underlying Dockum Aquifer and other sources.
In the s and s, the rate of groundwater mining , or overdraft, lessened, but still averaged approximately 82 centimeters 2. Increased efficiency in irrigation continues to slow the rate of waterlevel decline. State governments and local water districts throughout the region have developed policies to promote groundwater conservation and slow or eliminate the expansion of irrigation.
Generally, management has emphasized planned and orderly depletion, not sustainable yield. Depletion results Center-pivot sprinklers are among the irrigation methods used in the High Plains.
Large quantities of groundwater pumped from the Ogallala Aquifer allows these semiarid western lands to yield abundant harvests. The average specific yield for the High Plains Aquifer is about 0. This means that only 15 percent of all the water available in the aquifer can be recovered using irrigation pumps, while the rest remains unused and locked up in the unsaturated zone.
Groundwater depletion problems could be forestalled if this presently nonrecoverable water could be forced to the saturated zone. One experimental means of accomplishing this is by injecting air into the unsaturated zone, which breaks down capillary action and permits the movement of water down to the saturated zone. Air injection experiments have shown positive results for very localized areas. However, the widespread applicability of this technology has not yet proven effective.
Groundwater contamination in the Ogallala became an issue in the s. In its natural state, the High Plains Aquifer is, for the most part, of high quality. The water is generally suitable for domestic use, stock watering, and irrigation without filtration or treatment.
Surveys of groundwater samples have detected traces of pesticides and nitrates. Sources include irrigated agriculture and confined livestock feeding operations. The percolation rates of contaminants from the surface to the water table have not been established in the areas where polluted water has been found.
The future economy of the High Plains depends heavily on the Ogallala Aquifer, the main source of water for all uses. The Ogallala will continue to be the lifeblood of the region only if it is managed properly to limit both depletion and contamination. Kromm, David E. White, eds.
Groundwater Exploitation in the High Plains. Lawrence: University Press of Kansas, Sophocleous, Marios, ed. Lawrence: Kansas Geological Survey, These invasive species have a higher tolerance for the decrease in groundwater and can better adapt to this environment. However, this invasion by exotic species greatly decreases the biodiversity of the ecosystem Stromberg et al.
In addition, with the boom of the agriculture industry and urban growth, there are increased amounts of agricultural run-off that is high in nutrient content.
When this run-off drains into the groundwater and subsequently enters into the wetlands and estuaries, it can cause eutrophication of the ecosystem.
This greatly threatens the health of the ecosystem, as there is a significant reduction in oxygen and an increase of carbon dioxide in the system. In addition to agricultural run-off, another significant issue is industrial waste that inadvertently ends up in such ecosystems. Many of these ecosystems are also considered as the natural filtration system of the region. Hence, usually many of the contaminants end up in these ecosystems, harming the wildlife and the habitat.
Thus, overpumping groundwater and contamination from agricultural run-off has threatened the existence of these delicate systems. Although there are numerous federal agencies already in place, committed to restoring, maintaining and conserving ecosystems, many of these programs have only an "adequate" rating. In addition, these 14 different federal programs have overlaps and have limitations. For details on the federal programs, please refer to the Public Policy Section.
To streamline these programs, a new system should be implemented to unify these programs. By unifying these programs, they are able to consolidate their information, resources and strengths to improve on aspects, such as monitoring aquifer condition.
Presently, policies regarding groundwater are implemented on a state by state basis, and are highly variable. Some set specific depletion caps, others only say that water must go to "beneficial uses".
Many but not all states require permits for drilling and producing from wells; generally, wells for domestic purposes do not require a permit and go primarily unregulated.
Outlined below is each state's current approach to groundwater management. Colorado In Colorado, one must obtain a permit to use groundwater. Water permits are considered property rights and can be bought and sold independently of the land upon which the well rests.
This commission is in charge of issuing and changing water permits. These districts can put additional rules regarding groundwater management into place; however they cannot issue permits. Only the Colorado Ground Water Commission can issue or change permits. Also, since new large-capacity well permits will not be issued if they are closer than 0.
To change a permit "requires that the well be limited to the average annual historical consumptive use and proof that no material injury will occur to other vested water rights" McGuire et al, , McGuire et al, , In Kansas, anyone with a permit or a vested right can use groundwater for nondomestic purposes.
A vested right means that that well had been pumping water since June 28, and therefore has a right to continue pumping; however, water pumping for domestic purposes is not regulated by permits. In all cases, a landowner must "use the water for beneficial purposes" McGuire et al, , The governing bodies for groundwater in Kansas are the five Groundwater-Management Districts. These districts are in charge of regulating nondomestic water use and they can propose regulations that do not conflict with state law.
Of these governing bodies some follow the idea of "safe yield" and others follow the idea of "allowable depletion". In Nebraska, one has the right to use "a reasonable amount of the ground water under their land for beneficial use on that land" McGuire et al, , Each NRD must have a ground-water-management-plan, approved by the NDNR, which outlines what they will do to manage depletion and quality concerns in their area. NRDs are also in charge of distributing well permits, which are required for all wells constructed after September except for those "used exclusively for domestic purposes and for test holes and dewatering wells used for less than 90 days" McGuire et al, , In areas where there is not NDNR governance, residents follow the Nebraska correlative rights doctrine that states that residents must share when groundwater supplies are limiting McGuire et al, , In New Mexico, water rights are based on the prior appropriation doctrine.
There are six groundwater basins all governed by the State Engineer. The State Engineer has the authority to grant permits. In general, the State Engineer approves most permits for domestic use.
For nondomestic use, however, the State Engineer will approve permits only if these 4 criteria are met: " 1 no objections are filed, 2 unappropriated water exists in the basin, 3 no infringement on the water rights of prior appropriators occurs, and 4 it is not detrimental to the public welfare or the water conservation goals of the State" McGuire et al, , The State Engineer determines the validity of criteria 2 by monitoring the groundwater levels 9 to 25 miles around a proposed well site.
If water levels decrease by 2. In addition, water rights are bought and sold independently of the land upon which the well sits. As long as the State Engineer approves, water rights can be sold for out-of-state use McGuire et al, , Oklahoma management policy is based on the reasonable use doctrine. The amount of water withdrawn is determined by the OWRB and varies from region to region.
This amount is determined by the maximum amount of water that can be withdrawn and still secure the availability of water at least 20 years from the time of the license; hence, the specific amount of water is uniquely calculated for each region. This amount is adjusted yearly when each license holder must check in with the OWRB and report how much water they pumped and set limits for the amount of water allowed for the next year.
South Dakota law says that all water is a public resource. However, water can be withdrawn once a permit has been approved. The state also sets a specified amount of water that can be withdrawn. Generally, the amount of water withdrawn does not exceed the natural recharge rate. All permits, other than irrigation permits, can be transferred to out-of-state.
Most of the groundwater is found below the Rosebud Indian Reservation land. Hence, these tribes have pre-dominant control over the use and development of the groundwater McGuire et al, , Wyoming management policy is based on prior appropriation. Wyoming law mandates that all natural waters are property of the state. Permits are given out to users, given that beneficial use is demonstrated.
There is no specific limit on the amount of water that can be withdrawn. If the user would like to change any aspect of the permit, the user must first appeal to the state.
No permits are needed if the out-of-state transfer is less than 1, acre-feet per year McGuire et al, , Texas regards groundwater that is still in the aquifer as a public resource. However, once the groundwater is withdrawn, it is specific to the landowner. Groundwater can be sold to other locations, including out-of-state.
No landowner can purposefully withdrawal groundwater for "malicious reasons or to willfully waste the water". Once filled, rainwater and runoff can reach the large cracks in a dry playa—which is essential for recharge to occur—rather than collecting in the pit. The shallow water that spreads across the playa also allows plants to flourish, which in turn provides important food and habitat for migrating birds and other wildlife. Contact Us Donate Now. Search for:. Filling a pit in a playa.
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