Overview of Upstream Sample Clauses

Overview of Upstream. Issues Upper and middle Xxxxx Fork River: Although heavy metals pollution in the headwaters of the Xxxxx Fork is the most acute problem in the upper basin, nutrient pollution affects the largest portion of the basin and is the primary interstate water quality issue. Excessive nutrients in the river originate from a combination of point and nonpoint sources. Ambient concentrations of phosphorus and nitrogen have led to blooms of filamentous algae in the river above Missoula and heavy growths of slime, or diatom algae, below Missoula. Algae impair beneficial uses of the river, such as irrigation and recreation, and in large concentrations can deplete dissolved oxygen needed by fish and other aquatic organisms. The 525 study showed that excessive levels of algae caused water use impairment in up to 250 miles of the Xxxxx Fork, to its confluence with the Flathead River. This impairment was the basis for the development of the VNRP, as described on Pages 3-4. Most of the Xxxxx Fork River, as well as its tributaries, is classified as a B-1 waterbody, which means that the river’s quality shall be maintained for all beneficial uses.