Rio Grande Surface Water Quality: Dirt, Germs, and Salt

The Rio Grande is a critical resource for both the United States and Mexico in terms of industry, agriculture, domestic and public water supply, recreation, and wildlife habitat. However, along its journey, factors such as high salt content and sediment loads, inconsistent water flow, and inputs of various other pollutants such as nutrients and E. coli can limit the use of the Rio Grande for both human and aquatic life. These water quality challenges arise from both “natural” stressors, such as climate variability and geologic sources of salinization, and “human” stressors, such as bacterial and nutrient contamination from urban stormwater, agricultural return flows, and wastewater treatment plants (WWTPs), altered hydrology, and increasing/changing water demands. This presentation will provide an overview of three of the most significant surface water quality challenges for the Rio Grande in New Mexico—salinization, nutrients, and E. coli. The present-day system will be contrasted with the pre-development system, with the present day to help inform how the stressors mentioned above impact the Rio Grande, providing context for these challenges. Current efforts to address these issues will also be discussed.