Two Dimensional Groundwater and Sediment Modeling Studies, Santa Ana River Basin, California

摘要

The effects of the proposed Mentone Dam and reservoir sedimentation on net groundwater basin storage and net effect on potentiometric levels (groundwater levels) within the Bunker Hill groundwater basin were evaluated. It was found that approximately 0.8 square miles of the proposed reservoir area, immediately upstream of the dam, would be affected by sediment deposition under the most sever hydrologic and watershed burn conditions considered reasonable to the area. Gross sediment production rates used in design of reservoir storage allocation were confirmed by use of a mathematical sediment transport model. The analysis included effects of the dam on historical potentiometric levels and basin storage from water year 1945 through 1980 assuming the dam and sedimentation effects to be in place in 1945. It was found that no net effect on groundwater basin storage results from the dam and reservoir area with application of relocated groundwater recharge facilities within project limits. Localized depressions in potentiometric levels in the immediate vicinity of the dam would be accompanied by localized increases in potentiometric levels in other parts of the groundwater basin as a result of the project.