Sheet Flow Construction Erosion Control

April 7, 2020

Silt Fence Water Bars Fail

Photo: David Jenkins

Whenever I see something like this, it makes me think that the site owner/contractor either didn’t know what they were doing or bit off more project than they could chew, or both. These guys cleared, grubbed and graded something over 80 acres starting in late summer, failed to phase the work, failed to use soil cover practices, failed to listen to the experts and got nailed by the fall rains.

Erosion control is really about water control: reducing volume, preventing it from becoming turbid, and controlling where it goes. By the time the rains hit this project, there was too much water, it was too dirty, and there were too few options for controlling where it went.

In addition, they refused to set up a chitosan-enhanced sand filtration system to treat and discharge water; this left them no options and too much turbid water that had nowhere to go. As a result, they hammered a wetland, were fined heavily, and were shut down for months.

Silt fences are not meant to control water, convey water, filter water; they are designed to control eroded sediment. Ditches, berms (rock, gravel, triangular silt dikes, etc.) would have been better choices at this location. Not opening up so much area so late in the season would have been the best option. Their means and methods did not save them time or money.

February 11, 2020

Locating Check Dams

This is part 2 of 2 videos I made where I discuss locating check dams in a ditch.

February 10, 2020

Dams in a Ditch

This is part 1 of 2 videos I made explaining how to locate check dams in a ditch.

May 14, 2018

Geotextile-Foam Check Dam

Yet another example of poorly installed and maintained check dams. Even worse, it’s hard to install geotextile-foam check dams incorrectly. Here is an installation detail to use as a guide for proper installation:Geotextile-encased Check Dam

Video: David Jenkins

May 17, 2016

Inspecting-Check Dams Need Low Center Point

Check dams need to be installed with a low center point.  This means  that the center of the dam is at least 6 to 8 inches lower than the outside edge; 12 inches in areas where intense rainfall occurs. If the center is higher than the outer edges, water will run around the dam and erode the side slopes of the ditch, causing erosion. If the ditch is shallow and you are using triangular silt dikes, you might need to add sand bags to create a point that is lower than the center.

Video: David Jenkins

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