Fecal Coliforms in the Rio Grande: A Risk to Human Health

Tompkins, Erin L., Fecal Coliforms in the Rio Grande: A Risk to Human Health. Master of Public Health (Environmental Health), December 2004, 45 pages, bibliography, 33 titles. The Rio Grande around Laredo, Texas/Nuevo Laredo, Mexico was designated for primary contact reaction by the EPA. However, monthly sampling over a ten-year period in this section of the river may show otherwise. Fecal contamination of the Rio Grande in this area may be a source of illness to the population. Four sites in Laredo area were tested for fecal coliform density and rate of flow. Rainfall data from the USGS was used for comparisons. The rate of flow of the Rio Grande had an impact on fecal coliform density at one site measured. Rainfall in Laredo had an impact on fecal coliform density at two measured sites, and was a significant predictor of density at these sites as well. A review of the designation for this river segment is recommended. More research is needed to determine the exposed population, and effects of high coliform densities on downstream communities.