Linear BMP,s Gravel Bags

So now you've had time to consider Worst Practices, but what about Best Practices? What are Best Practices? Best Management Practices, BMP's are a combination of materials and procedures to minimize sediment and other pollutants from entering the storm drain system. These BMP's can be used singly or in combination with other BMP's. The following is a simple description of basic linear BMP's used to protect areas outside of the construction zone. The first consists of a Gravel Bag Berm, which typically consists of a double high line of gravel bags placed along the perimeter of a project. The objective of this Bag Berm is to slow rain related run-off long enough that the sediments settle or dropout behind the bags, and that only Clear Water runs out of a site. The same objective is achieved using check dams and gravel bag chevrons, on sloped areas with added benefit that the run-off is also slowed down sufficiently to reduce water velocity and therefore the effects of erosion on the slope surface.

As you can see from the pic on the lower right, it is far from a perfect science, but if implemented properly can go a long way to mitigating contaminated run-off.

Also keep in mind that the new EPA standards will be adopted by the revised California NPDES Permit, which in turn means your TMDLs will be much more tightly monitored.

Worst Practices 03/23/09

As you may well know the Clean Water Act, and specifically the states NPDES Permit are the guiding documents for Storm Water issues within the state (Ca). I was recently in Orange County Ca, and saw a great example of worst practices, as opposed to best practices. Being a certified erosion & sediment control person, I was absolutely amazed to see the complete lack of understanding of basic controls, and proper implementation. There appeared to be little or no regard for either the environment, the regulations, the construction companies reputation as a polluter or the trade craft of erosion & sediment control. I realize that budgets are beyond tight, but I also realize that failure to implement properly, the most basic of BMP's, Best Management Practices, violates us all. It allows pollutants, sediment and other contaminants to flow into our storm drains and straight out to the ocean. As you probably know storm drains, unlike sewers, have no treatement and flow straight into the streams and rivers and ultimately to the ocean.