Ground-Water Flow Model of the Sierra Vista Subwatershed and Sonoran Portions of the Upper San Pedro Basin, Southeastern Arizona, United States, and Northern Sonora, Mexico

Pool, D. R.; Dickinson, Jesse E.

Abstract:

A numerical ground-water model was developed to simulate seasonal and long-term variations in ground-water flow in the Sierra Vista subwatershed, Arizona, United States, and Sonora, Mexico, portions of the Upper San Pedro Basin. This model includes the simulation of details of the groundwater flow system that were not simulated by previous models, such as ground-water flow in the sedimentary rocks that surround and underlie the alluvial basin deposits, withdrawals for dewatering purposes at the Tombstone mine, discharge to springs in the Huachuca Mountains, thick low-permeability intervals of silt and clay that separate the ground-water flow system into deep-confined and shallow-unconfined systems, ephemeral-channel recharge, and seasonal variations in ground-water discharge by wells and evapotranspiration. Steady-state and transient conditions during 1902-2003 were simulated by using a five-layer numerical ground- water flow model representing multiple hydrogeologic units. Hydraulic properties of model layers, streamflow, and evapotranspiration rates were estimated as part of the calibration process by using observed water levels, vertical hydraulic gradients, streamflow, and estimated evapotranspiration rates as constraints. Simulations approximate observed water-level trends throughout most of the model area and streamflow trends at the Charleston streamflow-gaging station on the San Pedro River. Differences in observed and simulated water levels, streamflow, and evapotranspiration could be reduced through simulation of climate-related variations in recharge rates and recharge from flood-flow infiltration.

Genre:

USGS Numbered Series

ProdID:

80075

Citation Author:

Pool, D. R.; Dickinson, Jesse E.

Citation Contributing Office:

USGS Arizona Water Science Center

Citation Datum:

Citation Day:

Citation Edition:

Version 1.0

Citation Editor:

Citation End Page:

Citation Issue:

Citation Keywords:

Citation Language:

ENGLISH

Citation Larger Work Title:

Citation LatN:

0320000

Citation LatS:

0304500

Citation LonE:

-1094500

Citation LonW:

-1104500

Citation Month:

Citation No Pagination:

Citation Number Of Pages:

Citation Online Only Flag:

Citation Phsyical Description:

vi, 49 p.

Citation Projection:

Citation Public Comments:

Prepared in cooperation with the Upper San Pedro Partnership and Bureau of Land Management

Citation Publisher:

Geological Survey (U.S.)

Citation Series:

Scientific Investigations Report

Citation Series Code:

SIR

Citation Series Number:

2006-5228

Citation Search Results Text:

Ground-Water Flow Model of the Sierra Vista Subwatershed and Sonoran Portions of the Upper San Pedro Basin, Southeastern Arizona, United States, and Northern Sonora, Mexico; 2007; SIR; 2006-5228; Pool, D. R.; Dickinson, Jesse E.