Baltimore Ecosystem Study Institute of Ecosystem Studies

2011 BES Annual Meeting Presentation and Poster Abstracts

Impact of urban development on groundwater storage in Baltimore
Bhaskar, Aditi
Co-Authors: Aditi S. Bhaskar, Claire Welty, Andrew J. Miller, and Reed M. Maxwell

Groundwater storage is subject to a variety of impacts from urban development. This has led to studies showing increases, decreases, as well as little change in groundwater storage due to urbanization, depending on the combination and magnitude of various characteristics evaluated. Our study focused on investigating the effects on groundwater storage resulting from four factors: (1) presence of impervious surface cover; (2) infiltration of groundwater and stormwater into wastewater pipes (I&I), (3) reduced vegetative cover, and (4) other anthropogenic discharges and recharges such as water supply pipe leakage and lawn irrigation. We applied our previously-developed coupled groundwater - surface water - land surface model ParFlow to the Baltimore regional area as an analytical tool. Through analysis of a six-month time period in which scenarios isolating these four factors were simulated, we found that I&I led to a larger decrease in subsurface storage compared to impervious surface cover. Other anthropogenic discharges and recharges, primarily water supply pipe leakage and lawn irrigation, caused increases in groundwater storage, as did reduced vegetative cover to a lesser degree. Although the scale of our model prevented us from simulating the impact of stormwater management, our findings point to the importance of considering urban subsurface infrastructure, and not just imperviousness, when managing to restore near-natural hydrologic functioning.