Friday, July 27, 2012
SUMMER BROWN WATER
From WATERWORKS An Outdoor Column by Gordon Prickett for the 8/1/2012 Aitkin Independent Age BROWN WATER Since the storm of June 18th and the extreme flood events that have followed in Aitkin County, many of our lakes have changed from their normal clear transparency in the Spring to waters with a brown-colored stain and a substantial reduction in measured clarity of the lake water. Most lakes have risen more than a foot above the Ordinary High Water Level, where the vegetation changes from aquatic to terrestrial. In some cases the lake levels by June 26th were two feet over normal high water. Due to torrential rains falling on saturated ground, extreme runoff has flushed soils and lawn chemicals into the lake. Wave action and boat wake action have eroded the soils on the shoreline, and trees rooted on the water’s edge have toppled. It will be some time, probably not until next Spring, before our lake water quality will return to normal. In the meantime there are a few lessons to be gained from the difficult weeks that we have just come through. LEARNING FROM HIGH WATER Anything that can absorb the energy of rushing water, slow the flow, will prevent or at least limit damaging erosion of the lakeshore. Rain gardens that collect and absorb rainwater, as well as rain barrels to store and use the rain for watering, are helpful measures in dealing with storm water. A zone on the edge of the lake that is not mowed and left to natural vegetation will act to buffer the downhill force of rain runoff. Last week I was asked to examine a lake property where unlicensed vehicles had been stored outside for years. Junked cars and trucks in the Shore Impact Zone are more than unsightly to neighbors. They contain hydraulic fluid, grease, gasoline, and oil that eventually can contaminate the area and pose a risk to lake water quality. Yes, this is a violation of Aitkin County’s recently revised Shoreland Management Ordinance. But until the Zoning Office hears about it, the vehicles remain. Then there are the 57 DNR public access docks on the best fishing lakes in the county. The road we use to back in our boat trailers where I live has been badly eroded. Looking at several other DNR boat landings in the county I have seen that these sites are seriously eroded, with much washed-in sediment. Repair is needed. I have also learned that only 28 lakes in Aitkin County are gaged, so that in an emergency it is a task for a surveyor to find out how high the lake level is on Gun Lake, Big Pine Lake, Long Lake, Nord Lake, or Hammal Lake. We have much work to be ready for the flood next time.