Sediment and Erosion Problems in Our Watersheds
Have you ever seen dirty or muddy water running off construction sites into local streams? Although a small amount of cloudiness is natural in some streams, particularly after a large rainstorm, too much sediment can cause problems. Excessive amounts of sediment in our streams can be caused by:
- Runoff from construction sites or land-disturbing activities
- Physical dumping of soil and debris
Problems caused by excessive sediment in streams include:
- Unsightly waterways
- Loss of important topsoil
- Stream bank instability
- Smothering of the spaces between rocks where fish lay their eggs
- Cloudy water, which prevents fish from seeing their food
- Abrasion of fish and other stream life
- Reduced flow-carrying capacity in the stream channel due to sediment settling (which increases the potential for flooding)
- Diminished water quality
- Other pollutants carried by or attached to the sediment (such as phosphorus and petrochemicals)
Sometimes frogs are smothered by sediment in Montgomery County streams. Sediment causes several problems for aquatic life. It smothers living organisms and abrades or coats their skin; it settles in the spaces in which fish and other creatures lay their eggs; and it makes the water cloudy, making it difficult for creatures to find food.
Sediment in our streams not only is a pollutant but also carries other pollutants attached to the sediment particles.
Return to Top
What To Do about Sediment Runoff Problems
Construction or Land-Disturbance Site (greater than 5,000 square feet)
You can help prevent and limit sediment loading into our local streams. If you spot a construction site or any other land-disturbing activity that appears to be a construction site that requires a permit (greater than 5,000 square feet) with discolored or muddy water running off it, please report it! (Construction/land disturbance sites less than 5,000 square feet aren't required to have a sediment and erosion plan and don't fall under the Department of Permitting Services jurisdiction.)
Here are some examples of sediment violations and problems you can report:
- An abandoned construction site where sediment control measures, such as plastic silt fences, are frayed or worm out and not functioning as intended. These devices might need to be replaced to prevent sediment erosion and runoff.
- Streams adjacent to construction sites or land-disturbing activities with excessive siltation where you can see a direct flow connection to the construction site.
- Sediment control practices (such as silt fences) that have been breached because of excess water or sediment build-up.
- Other failing, inadequate, or improperly maintained sediment control best management practices on a site that is permitted for construction or land disturbance.
To report a potential violation, contact the Department of Permitting Services at 311, or submit a complaint online.
A permitted construction/land-disturbance site must have a sediment control plan as part of its permit.
A permitted site should have adequate, functioning sediment control measures (such as silt fences) in place.
One common sediment control measure is a gravel entryway, which prevents trucks from tracking sediment from the disturbed site onto the road.
Another sediment control measure is a pond into which the site drains so that sediment can settle before water is allowed to discharge into nearby creeks.
This sediment problem occurred during a rainstorm, when the sediment ran off the site and entered the storm drain system, which flows directly into local creeks.
Report sediment runoff problems you see at permitted construction sites to the Department of Permitting Services at 311.
Return to Top
Stream Bank Erosion
If you spot a stream bank with active erosion or collapse, and sediment is discharging into the stream, report it to the Department of Environmental Protection. DEP investigates complaints and will refer the problem to the relevant partner agency.
Common complaints include:
- Severe stream bank erosion on property. Often mowing, herbicide use, and tree removal up to the stream's edge make banks more vulnerable to erosion because of the absence of roots, which bind soil in place.
- Erosion of stream channels, which exposes sanitary sewer infrastructure.
- Stream channel erosion resulting from a water main or sewer main rupture.
(Cases are referred to the Washington Suburban Sanitary Commission.)
- Stream erosion that is causing damage to a public road.
(Cases are referred to the Montgomery County Department of Transportation.)
Stream erosion can expose utility mains.
At this home, the yard is caving into the stream. This type of problem is often caused by a lack of vegetation along the stream banks. The roots of trees and plants help to bind the soil and keep it in place.
An unstable stream bank can deliver a steady stream of excess sediment into the stream and downstream into our rivers.
Return to Top
Limits of Service
Please note that if the erosion problem is on private property, the only assistance that DEP provides is some technical assistance on how owners can solve the problem themselves.
DEP does not deal with erosion gullies and dry channels. Erosion gullies and dry channels are normally the responsibility of the property owner, except when they are part of the public storm drain system. Then DEP refers the problem to the Montgomery County Department of Transportation.
DEP does not deal with lot-to-lot drainage issues. Those issues sometimes are dealt with by the Montgomery County Department of Housing and Community Affairs when they are the result of one property owner doing something to his property (e.g., moving a downspout discharge point, filling in a backyard swale) that causes damage to an adjoining property.
Report erosion. It's helpful to provide as much of the following information as possible:
- Your contact information, for follow-up contact
- The location of the complaint with street address if possible
- The frequency and full extent of the problem
- Pictures or video
Return to Top