Urbanization alters the character and state of the land surface. Urban-induced anthropogenic recharge sources that include leaky utility lines, storm sewer systems, and storm-water catchments, as well as over-irrigation of lawns, parks, and golf courses, can be significant. However, data may be sparse and quantification difficult. A case study for Austin, TX, uses commonly available data to estimate recharge from leaky utility lines and irrigation return flows. The estimates indicate that these sources accounted for at least 5 percent of the total recharge between 1999 and 2009 and that on a monthly basis these contributions can vary from <1 percent to nearly 100 percent of the total recharge. Irrigation return flow was the most significant contributor in summer seasons; however, leakage from utility lines provided more total recharge. Urban recharge contributions were comparable to the mid-size watershed contributions over the 10-year period. These estimates are conservative and should be reevaluated as urbanization continues and as new data become available. Outcomes are relevant for habitat conservation, drought response planning, and urban groundwater management. Urban recharge can be important for buffering seasonal fluctuations during periods of low precipitation and springflow.

You do not currently have access to this article.