New! Recent Publication
Brief abstract
Many basins throughout the world have sparse hydrologic and geologic data, but have increasing demands for water and a commensurate need for integrated understanding of surface and groundwater resources. This paper demonstrates a methodology for using a distributed parameter water-balance model, gaged surface-water flow, and a reconnaissance-level groundwater flow model to develop a first-order water balance. Flow amounts are rounded to the nearest 5 million cubic meters per year.Citation
- Flint, L. E., Flint, A. L., Stolp, B. J., and Danskin, W. R., 2012,
- A basin-scale approach for assessing water resources in a semiarid environment: San Diego region, California and Mexico, Hydrol. Earth Syst. Sci., 16, 3817-3833, doi:10.5194/hess-16-3817-2012.
http://www.hydrol-earth-syst-sci.net/16/3817/2012/hess-16-3817-2012.html
PDF file of the journal article could be obtained here.
New monitoring well site being installed in the San Pasqual Valley
The USGS, in cooperation with the City of San Diego, will being installing a multiple-depth monitoring well site in the San Pasqual Valley beginning September 26, 2012. Drilling and installation of the site will take approximately 10 days.
The well site (SDLH) is located immediately east of Lake Hodges and is designed to monitor water levels and water quality in the river-channel deposits, the weathered granitic bedrock, and the hard granite. The water-level data will be monitored continuously, uploaded via satellite to the USGS database, and displayed on this project webpage, similar to other multiple-depth well sites in the San Diego area, such as the Santa Ysabel site (SDSY) located in the eastern part of San Pasqual Valley.
Next Deep USGS Monitoring Well Construction to Begin October, 2012
As a part of the ongoing San Diego Hydrogeology project, the United States Geological Survey (USGS), in cooperation with the Olivenhain Municipal Water District (OMWD), will begin installation of the next deep monitoring well site in the coming weeks at the San Elijo Valley Groundwater Basin. The purpose of the research well will be to better understand the geology of the lagoon area and to determine the quality and quantity of a deep water aquifer beneath the lagoon. The USGS will use the data collected to continue to map the geologic and hydrologic characteristics of San Diego; the OMWD will use the information from the well to assess the feasibility of developing a potable water source from groundwater underneath the lagoon.
To complete the San Elijo Valley Groundwater Project, USGS and OMWD are cooperating with the City of Encinitas, the City of Solana Beach, the County of San Diego Department of Parks and Recreation, the San Elijo Joint Powers of Authority, the San Elijo Lagoon Conservancy, and the United States Bureau of Reclamation. The scope of the study includes the San Elijo Lagoon area, upstream drainage, and the offshore continental shelf.
San Diego Hydrology Project
The first comprehensive geologic and hydrologic study for the San Diego area, California. This study will provide the integrated hydrogeologic knowledge necessary in this important and highly visible area of the United States and will serve as a role model for similar coastal settings throughout the world that have modest rainfall and small aquifers. Locally, results will help state and federal agencies, water purveyors, and consultants to understand the local surface-water, groundwater, and biologic resources and how these resources interact with each other, and to critique ideas and opportunities for additional groundwater development.
Two primary objectives
- Develop an integrated, comprehensive understanding of the geology and hydrology of the San Diego area, focusing on the San Diego Formation and the overlying alluvial deposits.
- Use this understanding to evaluate expanded use of the alluvial deposits and the San Diego Formation for recharge and extraction.
Map of completed and planned multiple-depth well sites in the San Diego Hydrogeology project. Click on image to download map in PDF format.
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