By Brian Hartman—Lead Compliance Manager // 2022-08-01
Sediment pollution is the most prevalent pollutant in lakes, rivers, streams, and wetlands throughout the country. At Earthworks, we conduct storm water inspections for residential, solar, industrial, and commercial construction projects to help minimize the impact of sediment pollution to these water bodies. Sediment pollution severely affects water quality, which in return has many negative effects on plant and animal life. Until you see these negative aspects in real life, there may be some disconnect in understanding why it is so imperative to minimize the impacts of sediment pollution.
For example, the impacts were evident during a recent fishing trip to Lake Osakis in Minnesota for the fishing opener. The trip began by fishing the early morning with no luck. The fishing was so poor that it was decided to relocate for the remainder of the day to Miller’s Bay, which is notoriously known for good walleye and sunfish. During the drive to the bay, there was a very distinct color variation in the water. Miller’s Bay was completely turbid with silt, with only a few inches of visibility while retrieving lures. Turbid water like this is horrible for fish health, fish eggs, fish vision, and aquatic vegetation. Blocking sunlight due to the sediment promotes change in water temperatures and bad algae growth. Water like this does not provide ideal fishing conditions, so the decision was made to move on as well.
“Judicial Ditch 2” in Osakis, MN flows into Miller’s Bay on Lake Osakis. It had rained the previous night, and a lot of sediment from construction activity upgradient of the bay had migrated into the lake via Judicial Ditch 2. If proper best management practices had been implemented upgradient of the bay, much of the sediment pollution into Lake Osakis could have been prevented that day. Some old-timer fishermen on the lake say that Miller’s Bay used to be their favorite fishing spot to go to on the lake. However, over the past 30 years, they have noticed a steady decline in good fishing here. One of the biggest factors for this decline is the repetitive flow of sediment into Miller’s Bay via the ditch. Miller’s Bay used to have a nice sand bottom with good vegetation that was favorable to fish. Now, there is a lack of vegetation and the bottom of the lake is coated with sediment. This is one example why it is important to conduct storm water inspections on construction projects and utilize proper best management practices.