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<br />project to develop water from the confined aquifer below 1000 feet in depth.
<br />Such a program of drilling and testing would be quite expensive; a single
<br />3000-foot deep test well properly drilled, logged, completed, and tested could
<br />cost between $200,000 and $400,000. If such a progran:....is!!nvisi one~?,..a..~ it
<br />some day must befor there to be_,~.~:liable databasE!ORthe~!!epc:gnfined
<br />aquifer, it is recommended that, c~operative fundin~ a.nd pqrticipa1;.ion by.
<br />several governmental agencies and/or water-use entities in the Valley would be
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<br />the most cost-effective approach.
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<br />The second recommendation of the study team is that consideration should
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<br />be given toa plan using the cQrifi'1ida-ncfunconfined aquifers as a managed
<br />ground Wi!:!;~.r..st.Qrag.e...J:.es,g.rvQjr.... Such a plan would likely involve using the
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<br />exi sti n~LJi!rge.can.a lsystern.S....and an extensive set of recharge basi ns, to
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<br />enhance the recharge of Rio Gr<!ndE!wat~.:.intothe unconfined aquifer. The
<br />'Closed Basin Project, currently under'-~onst;Uciion by the Bure~u of
<br />Reclamation, the existing Rio Grande Drain, and other existing or potential
<br />drainage systems could be used as part of the overall reservoir-concept
<br />system. Such a ground-water reservoir concept could afford Valley water users
<br />considerable flexibility in meeting Compact demands and irrigation needs
<br />during dry years.
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<br />One possible operational scenario would be to divert water into the
<br />canals and recharge facilities either under "free river" conditions whenever
<br />possible, or via upstream reservoir releases. The water would recharge the
<br />unconfined aquifer, which would be monitored and managed in conjunction with
<br />an extensive drain system, so as to maximize the volume of water available to
<br />shallow wells for irrigation, and minimize the evapotranspiration losses due
<br />to a water table within about six feet or less of the ground surface. During
<br />dry years, water stored in the unconfined aquifer could be used by pumping
<br />wells to supplement possibly inadequate ditch diversions, and Compact
<br />obl igatio_ns could be rnetby diverting irrigation return-flow water back to the
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<br />Rio Grande through the drainage system.
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<br />It may be possible to meet some of the capital costs of such a venture by
<br />contracting some portion of the available water to one or more towns or cities
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<br />S-7
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