Suggested citation:
Levings, G.W., Healy, D.F., Richey, S.F., and Carter, L.F., 1998, Water Quality in the Rio Grande Valley, Colorado, New Mexico, and Texas, 1992-95: U.S. Geological Survey Circular 1162, on line at <URL: https://water.usgs.gov/pubs/circ1162>, updated April 1, 1998.