USGS

Regional Water Table (2004) and Water-Level Changes in the Mojave River and Morongo Ground-Water Basins, Southwestern Mojave Desert, California

By Christina L. Stamos, Julia A. Huff, Steven K. Predmore and Dennis A. Clark

 

U.S. GEOLOGICAL SURVEY

Scientific Investigations Report 2004-5187

Sacramento, California 2004


In cooperation with the
Mojave Water Agency




Complete accessible text of report (792 KB PDF)
Complete accessible text of report cover (757 KB PDF)
Complete accessible text of Plate 1 (12.2 MB PDF)
List of USGS sites and California State well numbers (16.1 KB TXT)

To view PDF documents, you must have the Adobe Acrobat Reader (free from Adobe Systems) installed on your computer.
(download free copy of Acrobat Reader).

Abstract

     The Mojave River and Morongo ground-water basins are in the southwestern part of the Mojave Desert in southern California. Ground water from these basins supplies a major part of the water requirements for the region. The continuous population growth in this area has resulted in ever-increasing demands on local ground-water resources. The collection and interpretation of ground-water data helps local water districts, military bases, and private citizens gain a better understanding of the ground-water flow systems, and consequently, water availability.

     During March and April 2004, the U.S. Geological Survey and other agencies made almost 900 water-level measurements in about 740 wells in the Mojave River and Morongo ground-water basins. These data document recent conditions and, when compared with historical data, changes in ground-water levels. A water-level contour map was drawn using data from 500 wells, providing coverage for most of the basins. In addition, 26 long-term (as much as 74 years) hydrographs were constructed which show water-level conditions throughout the basins, 9 short-term (1992 to 2004) hydrographs were constructed which show the effects of recharge and discharge along the Mojave River, and a water-level-change map was compiled to compare 2002 and 2004 water levels throughout the basins.

     The water-level change data show that in the Mojave River ground-water basin, more than one half (102) of the wells had water-level declines of 0.5 ft or more and almost one fifth (32) of the wells had declines greater than 5 ft. between 2002 and 2004. The water-level change data also show that about one tenth (17) of the wells compared in the Mojave River ground-water basin had water level increases of 0.5 ft or more. Most of the water-level increases were the result of stormflow in the Mojave River during March 2004, which resulted in recharge to wells in the floodplain aquifer mainly along the river in the Alto subarea and the Transition zone, and along the river east of Barstow. In the Morongo ground-water basin, nearly one half (55) of the wells had water-level declines of 0.5 ft or more, and about one tenth (13) of the wells had declines greater than 5 ft. The Warren subbasin, where artificial-recharge operations in Yucca Valley (pl. 1) have caused water levels to rise, had water-level increases of as much as about 97 ft since 2002.

CONTENTS

 

Abstract

Introduction

Purpose and Scope

Description of Study Area

Acknowledgments

Geohydrology

Ground-Water Levels and Flow

Water-Level Changes

References Cited


Document Accessibility: Adobe Systems Incorporated has information about PDFs and the visually impaired. This information provides tools to help make PDF files accessible. These tools convert Adobe PDF documents into HTML or ASCII text, which then can be read by a number of common screen-reading programs that synthesize text as audible speech. In addition, an accessible version of Acrobat Reader 5.0 for Windows (English only), which contains support for screen readers, is available. These tools and the accessible reader may be obtained free from Adobe at Adobe Access.

 



Water Resources of California


FirstGov button  Take Pride in America button