A geographic information system was used to identify segments of the u
pper Trinity River drainage network that ate within various distance t
hresholds of solid waste landfills. U.S. Geological Survey digital lin
e graph (DLG) data were used to create a hydrography coverage for the
study area. Landfill coordinates were obtained from a database maintai
ned by the Texas Natural Resource Conservation Commission. At a map sc
ale of 1:100,000, 54 km (0.42%) of the drainage network are located wi
thin 100 m of at least one landfill and 25 km of these stream segments
are upstream of water supply reservoirs. The approach employed herein
can prioritize local hydrogeologic investigations and facilitate stra
tegic environmental monitoring to indicate potential landfill-derived
contamination of surface water resources.