A big part of what the District is busy doing involves regular maintenance of our dams. Maintenance includes mowing, repairing fences, exercising valves, and clearing downstream of the primary spillway works so it continues to drain normally.
Healthy vegetation on earthen dams prevents erosion which could lead to unstable slopes and deterioration of earthen spillways that can increase the dam’s risk of failure. You may notice taller vegetation around the dams compared to the height in your yard or adjacent park areas; the taller vegetation allows for healthier root system that is more drought tolerant and better prevents erosion. The District mows 1600+ acres per year. That’s equal to 1220 football fields!
Not all maintenance is for weather- or age-related deterioration. The dams are often victims of trespassing by off-road vehicles that can cause substantial damage to various aspects of the dam. Earthen dams require a healthy vegetative cover for protection from erosion. Vegetation is like the hard candy shell that keeps the chocolate from melting.
Even repeated foot traffic can damage the grass and lead to erosion creating vulnerabilities in the dam. Some of our dams are now within parks and allow for pedestrian and bicycle traffic on solid surface trails. Please help keep the dams safe and our maintenance costs down by respecting fences and staying on paths.
When it rains the dams detain drainage which leads to slower flows downstream protecting lives and property. The dams gradually release water until it reaches its typical design level. Exercising valves and clearing at the spillway works ensure the dams function properly.