I was just minding my own business last Friday, driving from Fred Meyer to the UPS store and passed this project. I told my wife I have to get a photo; she says okay since she knows me and my habit of stopping to take TESC photos.
I made a u -turn at the Wal Mart, drove back a block and stopped in the middle of the street to get this shot.
There is so much wrong here, where do I start? Clearly, dirt is tracked off of the project in the background, as you can see the sediment build up in the curb line. Someone told someone to put something in the swale to keep dirt out, then someone else installed this silt fence.
First off, silt fence needs to be trenched in and this just has a few rocks placed on the flap.
Second, they probably couldn’t trench this in anyway without tearing up the drainage swale.
Third, only two of the three curb cuts are backed by the silt fence.
Fourth, silt fence is a barrier, not a filter, and with the volume of water draining off the asphalt during a rain event, dirty water would just blow around and under the silt fence.
Conclusion, silt fence is never used in a water flow situation; it is only to contain eroded sediment from a sloped area. A better BMP here is a compost berm or something similar that would allow some water to pass but filter some sediment. Sand bags would work to keep everything out of the swale but then the dirty water would bypass to the next catch basin, which probably has a catch basin insert, which would collect sand and such but would not do anything for turbidity. So, what is the best BMP? Stop the !@#$ ing trackout in the first place!