Modeling Barton Springs Segment of the Edwards Aquifer Using MODFLOW-DCM
Publication: Sinkholes and the Engineering and Environmental Impacts of Karst
Abstract
The Barton Springs segment of the Edwards Aquifer is the sole source of water supply for about 45,000 people in and immediately south of Austin, Texas. For water management purposes, it is important to be able to predict the availability of groundwater in response to future development and potential droughts. The Edwards Aquifer comprises heterogeneous carbonate rock strata that have developed a well-connected network of karst conduits. This karstic geological structure makes aquifer characterization and groundwater modeling challenging. Previously, Scanlon et al. (2001) developed a two-dimensional groundwater model for the Barton Springs segment using MODFLOW. The karst conduits were not explicitly represented in the model. Instead, the study area was divided into 9 zones for which the transmissivities were obtained through calibration. We revisit Scanlon et al.'s work in this study by using MODFLOW-DCM, a MODFLOW module developed to represent flow through karstic aquifers. MODFLOW-DCM adopts a dual-conductivity approach in which the aquifer is conceptualized as being composed of two interacting flow systems, i.e., the background matrix and the karst conduits. This approach allows karst aquifers to be modeled as coupled systems, and thus allows aquifer dynamics related to karst conduit flows to be accurately simulated. Our preliminary results show improved matching of both water level measurements and spring discharges records.
Get full access to this chapter
View all available purchase options and get full access to this chapter.
Information & Authors
Information
Published In
Copyright
© 2005 American Society of Civil Engineers.
History
Published online: Apr 26, 2012
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.