By Tammy Allen, Restoration and Protection Unit Manager, Water Quality Control Division

Nitrogen being applied to growing corn. Credit: Lynn Betts/Photo courtesy of USDA NRCS

Unlike pollution that comes out of the end of a pipe into a stream or lake, nonpoint source pollution makes its way to Colorado’s waterways as runoff across the land when it rains or snows. As is the case nationally, nonpoint sources of pollution cause the majority of negative impacts seen in Colorado’s streams and lakes. In some cases, these impacts lead to public health risks from pollutants such as pathogens or those that bioaccumulate up the food chain to dangerous levels. Fish and the aquatic communities on which they rely are also impacted which can affect recreation and the state’s tourism economy. Nonpoint source pollution is not regulated in Colorado which makes controlling these sources everyone’s responsibility.

In order to fulfill its mission to protect and restore water quality for public health and the environment, the Colorado Department of Public Health and Environment (CDPHE), Water Quality Control Division (WQCD) relies on help from partners to voluntarily address nonpoint sources of pollution that are causing significant water quality impacts. Based on the WQCD’s ongoing evaluation of water quality in the state, the WQCD prioritizes its work with these partners to address nonpoint sources of pollution causing the most statewide impact. To that measure, the WQCD has been working with partners to address pollutants such as metals from legacy mining and selenium from irrigated lands.

There are many nonpoint sources of pollution beyond those tied to metals and selenium, some of which are not addressed in the WQCD’s priorities because water quality standards or other pieces of the regulatory framework upon which the WQCD relies are not yet in place. Nutrients are an example of nonpoint source pollution that have received some attention in Colorado and are now increasing in priority because the WQCD has built a foundation to support the development of statewide nutrient values. This foundation is in Regulation 85, the Nutrients Management Control Regulation.

Nutrients, such as phosphorus and nitrogen, are elements that all living organisms need to survive. However, when there is too much phosphorus or nitrogen, negative water quality impacts begin to happen. Excess nutrients can lead to overgrowth of algae, some of which can emit toxins that are harmful to people, pets and aquatic life. These algal blooms also consume large amounts of oxygen that fish and other aquatic life need to survive. Too much nitrogen in drinking water can be harmful to infants and the chemicals needed to treat nutrient-polluted drinking water can pose risks to public health.

Some of the primary sources of nutrient pollution are fertilizer runoff, animal manure, sewage treatment plant discharges, stormwater runoff, car and power plant emissions, and failing septic tanks. Pollution from agricultural operations is recognized nationwide as a significant source of nutrients that can have a negative impact on the health of watersheds. In Colorado, the current thinking is that agriculture is not as significant a source of nutrient pollution as in other parts of the country. However, in order to address all potential sources of excess nutrients, Regulation 85 encourages the WQCD to proactively collaborate with the agricultural community on voluntary nutrient controls, information and education campaigns about nutrients and monitoring of nutrients to better understand sources and effectiveness of nutrient controls. The WQCD is doing this in partnership with Colorado State University (CSU) through a number of projects.

1. South Platte Agriculture Nutrients Committee (SPAN): The SPAN, led by CSU, is creating an online library of best management practices for agricultural producers to reduce nutrient pollution to surface waters.

1. CSU Agriculture Outreach Committee: The WQCD is partnering with CSU to produce outreach materials about Regulation 85 that target agricultural producers. The outreach materials will include brochures, a dedicated website and videos.

1. CLEAN Center at CSU: The WQCD is participating in CLEAN Center initiatives. The CLEAN Center is a multi-agency collaboration lead by CSU. The mission of the CLEAN Center is to create knowledge, build capacity and forge collaboration to develop and demonstrate sustainable solutions for reduction of nutrient pollution in the nation’s water resources. The Center’s activities are organized around three major themes: understanding the physical system, understanding people and policy and enhancing the capacity for assessment and decision-making.

1. Soil and Water Analysis Tool (SWAT) Model: The WQCD is working with CSU to produce a statewide nutrient model. The model is based on the SWAT developed by the U.S. Department of Agriculture and Texas A&M University. This nutrient model will help us predict nutrient pollution problems resulting from various different population growth and agricultural production scenarios.

The WQCD’s work with the agricultural community to control nutrients pollution continues to gain momentum and the WQCD is always looking for new partners to help tell the story about the many successes accomplished by working together to address nonpoint sources of pollution.

Tammy Allen is the Restoration and Protection Unit (RPU) Manager in the Water Quality Control Division of Colorado Department of Public Health and Environment. In collaboration with many partners, the RPU team works to control nonpoint source pollution, a significant source of water quality impacts. The team also develops total maximum daily loads which are cleanup plans for waterbodies that are not meeting water quality standards and works on watershed, regional and statewide water quality planning. Tammy has been in the nonpoint source and water quality planning workgroups since joining the division over 7 years ago.  

Learn more of the basics of Colorado water quality through CFWE’s Citizen’s Guide to Colorado Water Quality Protection.