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The lowering of the water by any adjacent gravel operations will have a detrimental impact and should be required to be monitored and mitigated. The effect of fluctuating water levels are especially difficult for a fisheries management plan. The following information has been provided by Dr. Stephen Flickinger, Head of the Fisheries and Wildlife Management Department of Colorado State University. Dr. Flickinger has been active in the planning and management of the Ponds for more than twenty years. Impacts of Low Water Levels Dr. Stephen Flickinger "Deeper water means cooler water in the summer. In the Fort Collins area rainbow trout generally survive summer temperatures in ponds with 10 feet of depth, but they do not survive in ponds that are 8 feet or less deep. Loss of fish to winterkill is the result of a combination of factors, but shallow water makes winterkill conditions more likely. Shallow water promotes growth of aquatic vegetation which will die back during winter. Bacterial decomposition of the dead plants material requires oxygen. Shallow water equates to small volume of water holding dissolved oxygen for respiration, Hence, depletion of oxygen is likely, and also subsequent winterkill occurs. The duration of ice and snow cover also influences depletion of oxygen. Because typical winters in the Fort Collins s area are relatively mild, ponds can be fairly shallow and still support fish through the winter. Ponds 5-6 feet deep have carried fish through the winter more years than they have not, but certainly there have been years when ponds of that depth have had winterkill. Ponds in the Fort Collins area greater than 8 feet deep have not experienced winterkill. The third impact of low water levels is hard to quantify. Falling water levels during spawning inhibit reproductive behavior, but it is difficult to say how much or how fast the water must drop to disrupt the spawning process. If eggs have already been deposited near shore, a drop of a couple of feet in a few days will expose many of the eggs to drying. There may or may not be additional spawns at the new water level."