Forests and Water: A State of the Art Review for Colorado

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and the breakdown of the fire - induced water repellency, while recovery of the incised channels and removal of the accumulated sediment in downstream areas may take many years. Fewer studies have examined the effects of prescribed fires on erosion rates and water quality. Since prescribed fires do not cover as much area as the largest wildfires and usually are designed to burn at lower intensities, prescribed fires should have relatively small effects on water quality, especially if vegetative buffer strips are left along stream courses. Hillslope -scale monitoring of three prescribed fires in the northern Front Range is showing substantially lower erosion rates than following high- severity wildfires (Benavides- Solorio, 2003). 29 There is an increased interest in the effects of fire on drinking water quality. Both prescribed and wildfires can volatilize some of the forest organic matter. The result- ing organic compounds can be in either a dissolved or undissolved form. These compounds may discolor water and chelate heavy metals — particularly iron and man- ganese — from the forest soils. Iron imparts an orange color to the water, which is aesthetically displeasing, and the manganese imparts a metallic taste to the water. These changes in water quality were observed in Strontia Springs Reservoir after the Buffalo Creek fire, but there is little or no documentation of these effects in the scien- tific literature. The exact mechanisms or processes have not been identified. Several municipalities along the Colorado Front Range are concerned about this poten- tial effect on water quality, and this is another potential research topic.