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I' I I I I I I I I I I I I I I I I I I Executive Summary The North Fork of the Gunnison Volunteer Water Quality Monitoring Project was initiated in April 2001. The goal of this project is to obtain credible water quality information for the North Fork of the Gunnison watershed. This project is run entirely by local volunteers, with the donation of time and services from a variety of state, local, and federal organizations. Our sponsors include: Colorado State University Cooperative Extension, the North Fork River Improvement Association, the Colorado Watershed Network (River Watch Program), Colorado Department of Public Health and Environment, the Western Slope Environmental Resource Council, and the Environmental Protection Agency (Region 8). This annual report summarizes the results of water quality monitoring conducted from April 2001 to April 2002, at seven monitoring sites located throughout the North Fork watershed. It represents the efforts of dozens of local volunteers, and hundreds of hours spent preparing and analyzing samples. Water quality monitoring assessed metals, nutrients, and bacteria concentrations at all samples sites. In addition, certain field parameters such as river temperature and dissolved oxygen were also measured. Samples were collected monthly, or in the case of bacteria samples, twice monthly during the summer. This monitoring information was not collected for compliance or regulatory purposes, rather this data is designed to give background information on water quality conditions in the watershed, help understand seasonal and natural variation in our area, and provide a basic understanding regarding how the North Fork River is performing relative to state stream standards. Water quality samples collected by the program indicated that overall the North Fork River has moderate to good water quality, given natural inputs that increase metals and dissolved solids (salts) concentrations in the river. These increases are often a reflection of the natural soils and geology of this area, which varies between highly mineralized and highly alkaline calcareous soils. Sample analysis found elevated concentrations of aluminum and total recoverable iron in the upper parts of the watershed (East Muddy Creek and the North Fork around Somerset), especially during and after stormwater runoff events. Selenium concentrations were close to the state standard of 5 parts per billion, especially at the downstream sites near the Pleasure Park. This varied seasonally. Other metals, such as arsenic and cadmium, were measured only at very low levels. More good news is that nutrient concentrations in the river are relatively low. Nitrate concentrations never approached the state standard of 10 milligrams/liter. Although increases in phosphorus could be observed after stormwater runoff events, this was likely a reflection of inorganic phosphorus absorbed to eroded soil particles. Ammonia concentrations have been mentioned as a concern in this area, but only occasional exceedances of the state standard were observed, often around Paonia. Potential sources ES-l