Development of Coupled Groundwater-Surface Water Model for Assessing the Impacts of Groundwater Pumping on Streamflow in the Middle Rio Grande Basin
Environmental Engineering Graduate Seminar
This study is focused on the Middle Rio Grande basin which extends from Elephant Butte Reservoir in New Mexico 297 kilometers to Ft. Quitman on the US (Texas)-Mexico (Chihuahua) border. This region is on top five most water-stressed places globally due to water scarcity. The channel of the Rio Grande is connected hydraulically to an underlying alluvial aquifer. Extraction of groundwater from the alluvial aquifer is suspected to substantially affect streamflow in the Rio Grande. This study is an attempt to simulate this system to provide information for water managers and other local policy makers.
A one-dimensional (1D) flow model has been developed by solving the groundwater flow equation with finite differences, estimating steady-state routing of flow in the Rio Grande, and coupling the groundwater and streamflow models with Darcy’s law model of channel-alluvial aquifer exchange. This model is simulating conjunctive groundwater and surface water considering Rio Grande River flow and irrigational multi-branched canals for agricultural usage, and pumping for both municipal and agricultural usage along all over the basins. The 1D flow model has been coded in MATLAB, where the groundwater flow, streamflow, and channel exchange equations are solved iteratively. Calibration of hydraulic conductivity, aquifer bottom, and return flow fractions occurs by minimizing the sum of the squares of the residuals between modeled and observed groundwater levels and stream-flows from January 1993 to January 2014. Groundwater (alluvial) database is attributed from USGS/New Mexico monitoring wells which is consisting of more than three thousands observation points throughout the calibration period.
This work will be useful to predict the future of middle Rio Grande. This will shows the effect of continuous regional pumpings on the aquifer, whether the over pumping of alluvial aquifer accompanied by channel’s losses will adapt to a sustainable system.
Monday, March 18 at 3:00 pm
Great Lakes Research Center (GLRC), 202
1400 Townsend Drive, Houghton, MI 49931