Trading quality for quantity : an assessment of salinity contamination generated by groundwater conservation policy in the Tucson Basin

Persistent Link:
http://hdl.handle.net/10150/191122
Title:
Trading quality for quantity : an assessment of salinity contamination generated by groundwater conservation policy in the Tucson Basin
Author:
Tinney, James Craig,1950-
Issue Date:
1987
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
The State of Arizona adopted strict groundwater conservation policies under the Arizona Groundwater Act of 1980. The Act mandates direct controls on groundwater use and provides incentives to seek alternative water supplies to offset the groundwater overdraft and restrict the expansion of municipal well fields. The City of Tucson, to reduce its groundwater dependency, is contracting for Central Arizona Project (CAP) water. CAP water comes from the Colorado River and carries with it nearly a ton of salts per acre-foot. Conservation programs being investigated by the city include reclaimed wastewater reuse for municipal use and artificial recharge. Salinity, a conservative contaminant, will rise as the water carrying it evaporates away during use. Some saline incidental recharge from wastewater irrigated acreage in the municipal well field is picked-up by groundwater pumpage in what is described as the municipal water-salinity cycle. The rate of salinity pick-up is compounded in the cycle. Those responsible for achieving groundwater conservation under the mandates of the Act do not include the costs generated by salinity damages and suffered by municipal water-consumers into their conservation plans. Salinity damages costs are generated by the direct use of CAP water and the use of degraded groundwater supplies. The study results show that under assumptions of limited groundwater dilution volumes the annual rate of salinity pick-up can range from about 1.4 percent to nearly 2.0 percent. An annual average pick-up rate of 2.0 percent could degrade Tucson's groundwater supplies from the present average salinity of 300 mg/1 to 1000 mg/1 in 61 years. Thirteen scenarios were evaluated and the present value of incremental costs of both salinity damage and expenditures associated with conservation were calculated. While estimates of salinity damage costs are many times lower than the conservation program expenditures, increased salinity in groundwater will lower the future capital value of the resource in the future if ignored.
Type:
Dissertation-Reproduction (electronic); text
Keywords:
Hydrology.; Groundwater -- Quality -- Arizona -- Tucson.; Saline waters -- Arizona.
Degree Name:
Ph. D.
Degree Level:
doctoral
Degree Program:
Renewable Natural Resources; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
Nunn, Susan C.; King, David A.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleTrading quality for quantity : an assessment of salinity contamination generated by groundwater conservation policy in the Tucson Basinen_US
dc.creatorTinney, James Craig,1950-en_US
dc.contributor.authorTinney, James Craig,1950-en_US
dc.date.issued1987en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThe State of Arizona adopted strict groundwater conservation policies under the Arizona Groundwater Act of 1980. The Act mandates direct controls on groundwater use and provides incentives to seek alternative water supplies to offset the groundwater overdraft and restrict the expansion of municipal well fields. The City of Tucson, to reduce its groundwater dependency, is contracting for Central Arizona Project (CAP) water. CAP water comes from the Colorado River and carries with it nearly a ton of salts per acre-foot. Conservation programs being investigated by the city include reclaimed wastewater reuse for municipal use and artificial recharge. Salinity, a conservative contaminant, will rise as the water carrying it evaporates away during use. Some saline incidental recharge from wastewater irrigated acreage in the municipal well field is picked-up by groundwater pumpage in what is described as the municipal water-salinity cycle. The rate of salinity pick-up is compounded in the cycle. Those responsible for achieving groundwater conservation under the mandates of the Act do not include the costs generated by salinity damages and suffered by municipal water-consumers into their conservation plans. Salinity damages costs are generated by the direct use of CAP water and the use of degraded groundwater supplies. The study results show that under assumptions of limited groundwater dilution volumes the annual rate of salinity pick-up can range from about 1.4 percent to nearly 2.0 percent. An annual average pick-up rate of 2.0 percent could degrade Tucson's groundwater supplies from the present average salinity of 300 mg/1 to 1000 mg/1 in 61 years. Thirteen scenarios were evaluated and the present value of incremental costs of both salinity damage and expenditures associated with conservation were calculated. While estimates of salinity damage costs are many times lower than the conservation program expenditures, increased salinity in groundwater will lower the future capital value of the resource in the future if ignored.en_US
dc.description.notehydrology collectionen_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.typetexten_US
dc.subjectHydrology.en_US
dc.subjectGroundwater -- Quality -- Arizona -- Tucson.en_US
dc.subjectSaline waters -- Arizona.en_US
thesis.degree.namePh. D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineRenewable Natural Resourcesen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairNunn, Susan C.en_US
dc.contributor.chairKing, David A.en_US
dc.contributor.committeememberFogel, Martin M.en_US
dc.identifier.oclc212627112en_US
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