Construction Site Stormwater Run-Off Control
Construction sites are at higher risk of polluting because of the work that they do. That is why MS4 communities are required to monitor construction activities that disturb more than an acre or more of land. Construction Operations are required to implement simple Best Management Practices (BMPs) to help ensure that they are protecting the stormwater and surface water from pollution. Concrete washout, sediment leaving the site, leaking fuels or other contaminants can percolate into the ground and contaminate groundwater or combine with stormwater and travel into our municipal storm drain system. Some examples of important best management practices that contractors and developers use are:
Keeping sediment on-site so it doesn’t track to roadways and
end up in the storm sewer on a one way trip to our waterways.
| Covering inlets protects storm drains.
||Gravel or other medium should knock
sediment off of tires as vehicle exits site.
Protecting our water from Concrete Washout.
Concrete washout is also a pollutant to our waterways. After concrete is poured, the chutes of concrete trucks, wheel-barrows, and hand tools must be washed off. Concrete washwater has a pH of near 12 (household bleach has a pH between 12-12.6). It also contains various metals, sand and sediment.
When concrete washout comes in contact with the ground it can alter the soil’s natural chemistry, killing living organisms and making it difficult for plants to grow in the future. What does not leach into the ground combines with stormwater to become runoff contaminating other soil or our waterways.