Sign 5

GPS Data 92.9161W 45.0058 N, This location is on the Brown trail Outer Loop in the West central area of Sunfish Lake Park, just East of the Washington County Landfill that was closed about 1975 and has been the subject of much remediation effort.

You are in the Oak/Maple forest, but this area has not yet been cleared of buckthorn, which makes up large amounts of the undergrowth. The trail to the North takes you to Sign 6 in the Northwest section of the Park. From there via Sign 7 you can reach the trail access point near Fire Station #2. The trail to the East via signs 4, 16, 17 and 20 takes you along the South shore of the big unnamed pond. The trail to the South takes you to Sign 3 and then to the Southwest section where buckthorn removal has been underway for about a year.

Sign #5  Trail Erosion

Thanks to glacial activity thousands of years ago, Sunfish Lake Park is full of wonderful rolling hills. You may occasionally notice what look like large ruts or gouges in certain steep trail sections, particularly after a heavy rain. Those ruts most likely have been caused by erosion, the removal or wearing away of the soil by water or wind. Soil erosion is more likely to occur in areas that have been disturbed or left bare. Erosion in general can cause nutrient rich topsoil to be washed or blown away leaving poor quality soil for plants to grow. With fewer plants to stabilize the soil, the area can remain exposed to further erosion. Soil erosion can cause sedimentation build up in wetlands and waterways that lowers the quality of the water. This build up of soil in waterways can also lead to flooding. Eroded land is also more prone to flooding.  Since degraded soil and plant cover aren’t able to hold as much water, more runoff can occur.  Although erosion is part of a natural process, human activity can impact soil erosion in a number of ways, both positive and negative.  To control the effects of erosion, careful attention must be paid to minimize the impact of human activities that disturb the natural layers of soil.

Many of the original trails in Sunfish Lake Park were built in the 1970’s for Cross-country skiing, some with steep, challenging grades. In winter the soil is frozen and erosion is reduced, but in warmer weather, snowmelt and rainfall washes the soil downhill. More recent trail construction has been done with careful planning to minimize erosion. The newer designs tend to have less steep grades requiring more switchbacks, and include features such as water diverters and smoother edges, to keep gullies from forming.