WSP11154 - Laserfiche WebLink

Home Browse Search

N ~. ',J l"'-....J objectives of this study are to (11 delineate the limits of the stream-aquifer system in the lower Colorado River valley and those adjacent basins that have significant subsurface hydraulic connection to the stream-aquifer system of the Colorado River; (2) define the geometry, altitude, and boundaries of a potentiometric surface (regul atory surface), wi thin the area del ineated in (1) below which water is presumed to be diverted from the Colorado River b~ pumping from wells; and (3) provide a tabulation of the inventoried wells within the regulatory surface boundary. Fieldwork began in FY90 and is continuing. More than 1,000 wells have been inventoried and entered in the Ground-Water Site Inventory data base. New aerial photographs and satellite images for thee area have been obtained. The subsurface 1 imi ts of the River Aquifer have been delineated in four localities by a gravity survey. The potentiometric surface of the River Aquifer is being defined with water levels of wetlands and wells and with river profiles of the projected annual highest monthly discharge for 1992-2001. Preliminary sets of maps showing the regulatory surface wi 11 be' avai 1 abl e during FY92, Dissolved Solids Estimation Project The objectives of this project were to (1) determine the availability and completeness of discharge and water-quality records for selected sites on the lower Colorado River from Imperial Dam to the southerly International Boundary with Mexico; (21 dev~lop techniques to estimate missing periods of records for discharge and dissolved solids; and (3) present monthly discharge and monthly dissolved-solids discharge for sites on the lower COloradp River from 1935 to the present, The District estimates the final report will be approved during FY92. Glen Canyon Environmental Studies Projects The Arizona District has been involved in evaluating the effects of Glen Canyon Dam operations on the hydraulics and sedimentation characteristics of the Colorado River through Grand Canyon National Park. Currently, four major projects are underway in cooperation with tne Bureau of Reclamation, 1. Beach Evolution Project, The objective of this project is to gain an understanding of the status and evolution of sand bars used as camping sites and as substrate for riparian vegetation, thus enabling the prediction of how future releases from Glen Canyon 'Dam wi 11 affect the sand bars. The objective is being addressed by five study elements: (1) inventorying sand in sand bars or sand available for rebuilding of bars; (21 developing a descriptive understanding of the evolution of sand bars; (3)