Nutrients: “A substance that provides nourishment for growth or metabolism,” according to Dictionary.com.
Nutrients in water – sounds good. Like a vitamin-water mix. However, like vitamins, nutrients are good in the right amount and can be problematic in too high a dose. When talking about nutrients in water, the most common components discussed are nitrogen and phosphorus. The problem with too much of these is that they can cause excessive amounts of algae to grow, which in turn uses so much of the oxygen in the water that other living things die. It is a process called eutrophication. It can severely harm fish and other aquatic life.
A primary source of excess nitrogen and phosphorus is waste-water treatment systems, while many agricultural practices such as the use of fertilizers can also affect streams.
In 2002, the Animas River through Durango experienced algae blooms, and with the possibility of low water levels again this year, the risk is again on some of our minds. Right now, the Animas River in New Mexico, from the state line down to Farmington, where it joins with the San Juan, is out of compliance with New Mexico’s nutrient standards. This is not a theoretical issue.
As is obvious to all of us, not all rivers and streams have the same natural water quality. High in the mountains, the water is cold, clear and clean. By the time the stream becomes a major low-land river, such as the San Juan through Farmington, it is warmer and carries a natural load of silt and higher levels of nutrients. Fish and other aquatic life vary in these streams, as well. The cold-water trout would not do well in the warm, nutrient-rich lower reaches. So clearly, any regulations dealing with water quality have to reflect these natural variations.
For a decade, the Colorado Water Quality Control Commission and hundreds of stakeholders from throughout the state have wrestled with developing nutrient standards for Colorado’s rivers and streams. In March, the commission preliminarily adopted a two-pronged approach to nutrients that reflects Colorado’s needs and abilities. The proposed rules recognize that meeting new standards will take both time and flexibility. The rules include a generous implementation timeline for wastewater treatment plants to upgrade their systems, and voluntary programs for farmers and ranchers.
The system the Water Quality Control Commission has set out will be refined to meet the individual needs of each stream or river during the regular review of water-quality standards done for metals and other pollutants, and treatment-plant reviews. Known as the triennial review process, each of Colorado’s nine river basins is studied in turn, and standards are determined. Under the new rules, these standards will now also include nutrients. The San Juan, Dolores and Gunnison basins will undergo this review process later this year.
The commission deserves all our thanks for crafting an inclusive process that led to a flexible and sensible program to begin to address nutrients in our rivers and streams.
firstname.lastname@example.org. Dan Randolph is executive director of the San Juan Citizens Alliance.