WSP01267 - Laserfiche WebLink

Home Browse Search

N ~ Ul W SUMMARY (CQntinued) Water supply Under the nQ-actiQn alternative, SQme changes WQuld be expected in the surface water supplies in the valley. Upstream develQpments WQuld cQntihue to. deplete the CQ1QradQ River, but present irrigatiQn supplies WQuld! be prQtected by water right laws. No. significant changes WQuld Qccur' in grQund water levels. Canal and lateral imprQvements under bQth alternatives A and B WQuld be de~igned to. prQv,ide the histQrical water carrying. capacity available. This ~Quld in turn permitirrigatiQn districts to. divert the same amQunt Qf walter as in the! past; therefQre, maximum diversiQns WQuld 'remain un- changild. With alternative B, reduced seepage lQsses and the elimination Qf admin!Latrative wastewater at the end Qf laterals CQuld increase adminis- tratijre 'waste spills frQmthe canals, which WQuld. be expec.ted, to. result in ani increase in wash flows during the irrigatiQn seaSQn.. .. GrQund water levels WQuld be expected to. decline near imprQved canal!, and laterals, a reductio.n that WQuld decrease winter. flQWS in washe~ and drains. Seepage frQm canals and laterals WQuld be reduced by apprQ~imately 39,500 acre-feet with alternative A and apprQximately 41,10P acre-feet with alternative B. Water. quality Under any Qf the alternatives, a significant change is nQt expected in saat lQading to. the CQ1QradQ River frQm surface sQurces. On-farm i~ prQvetnents WQuld cQntinue and salt lQading due to. seepagefrQm.farm ditchbs and deep percQlatiQn frQm irrigated fields WQuld decline.. lmplementing alternatives A or B WQuld be expected to. decrease the salin~ty Qf the CQ1QradQ RiverabQve the DQ1Qres River by abQut 13a,000 and 143,500 tQns annually and abQut 23 and 24 mg/L; respectively. Fishery and aquatic envirQnment CQ1Qr~dQ River Under the no-actiQn alternative and under alternatives A and B, flQws,in the CQ1QradQ River will cQntinue to. decrease as the Upper CQ1Q- radQ River Basin States develQP their share Qf the CQ1QradQ River. These flQW 'changes may affect fish PQPulatiQns, but accurate predictiQns Qf these: changes are nQt PQssible. LQcal fisherman use may increase sligh~ly as the Grand Valley PQPulatiQn grows. ~alinity reductiQns in the river under alternative A Qr B WQuld have no. me~surable impact Qn the existing fishery in the CQ1QradQ River dQwn~ streajn Qf the Grand Valley Unit. The water PQssibly gained during the irrig~tion seaSQn and lQst during the nQnirrigatiQn seaSQn WQuldalSo have nO. impact Qn the existing fishery. S-6 ',t r ~ , -!' C:(, .~ -j.'- , )1' ::- }1 -1 , " , ct. '" ;::, j ., . '~ ,.)j . -':t'! ;) L. 11 .~ ,.. '.~ -~I .~ I , ,