Iron County, sources of sediment are abundant and constitute the a major concern. Dirt and sand particles, from roads in town, erosion from gravel pits, and other sources of sediment are introduced into the river through storm drains. This is especially true in spring, when tons of sand and dirt used on the roads in the winter are washed into the river during the spring melt.
Sediment can affect a stream in a variety of ways. Trout populations are dependent on cold clean water and gravel stream bottoms. Brook trout, more than other species of trout need this kind of gravel substrate for their spawning grounds. The gravel protects the eggs and at the same time allows water flow over the eggs, supplying them with oxygen. When sedimentation occurs, dirt and sand particles settle over the bottom of the stream and suffocate the eggs. Similarly, aquatic insects are deprived of gravel substrate. High concentrations of sediment change the habitat for these aquatic organisms and in turn, decrease the amount of food available to trout. Additionally, sedimentation increases turbidity (clarity of the water). Suspended dirt and sand particles in the water transport pollutants, increase water temperature since darker water absorbs and retains more heat, and make it harder for fish to find prey.
Sediment can affect a stream in a variety of ways. Trout populations are dependent on cold clean water and gravel stream bottoms. Brook trout, more than other species of trout need this kind of gravel substrate for their spawning grounds. The gravel protects the eggs and at the same time allows water flow over the eggs, supplying them with oxygen. When sedimentation occurs, dirt and sand particles settle over the bottom of the stream and suffocate the eggs. Similarly, aquatic insects are deprived of gravel substrate. High concentrations of sediment change the habitat for these aquatic organisms and in turn, decrease the amount of food available to trout. Additionally, sedimentation increases turbidity (clarity of the water). Suspended dirt and sand particles in the water transport pollutants, increase water temperature since darker water absorbs and retains more heat, and make it harder for fish to find prey.
In the Iron County Watershed, sources of sediment are abundant and constitute the majority of immediate concerns. Numerous storm drains have poor outlets that either empty directly into the river, or drain at the top of a slope and result in gullies or washouts. Gravel pit operations near the river have also contributed tons of sediment from erosion.