Sheetflow Construction Erosion and Sediment Control

July 16, 2019

Tree Protection Using Orange Safety Fence

July 9, 2019

Managing Construction Stormwater on Concrete Tiltup Building Project

Video: David Jenkins

July 2, 2019

Biofence Specification

I am trying to get to 100% biodegradable, recycled, reusable, recyclable, low impact best management practices.  I have used burlap fabric fence several times, anytime it makes sense, really.  I use it whenever I can leave it in place to degrade, like on habitat or wetland work.  In one of the photos, plastic zip ties are used to attach the fabric to the wooden stakes; this is a mistake and has been changed to staples in the specification.

Biofence Specification

Materials
U. BIOFENCE
A. Biofence shall consist of 7 ounce or heavier uncoated burlap fabric at least 36 inches wide and 100 feet long. Wood stakes dimensions shall be a minimum 1 1/8 x 11/8 inches by 42 inches high.

Construction Requirements
18. Biofence
a. Stakes shall be driven into the ground a minimum of 12 inches and be spaced no more than 6 feet apart.
b. Fence ends shall be joined by wrapping ends together around a post 3 times and driven into the ground.
c. Burlap fabric shall be attached to the post in at least 3 places using staples or other method approved by the Engineer.
d. When used as a barrier fence, fabric shall not be trenched into the ground. When used as a silt fence, a minimum 8 inch flap shall be left at the bottom and held in place with straw wattles staked in as detailed in item 9 above.

Payment
C. Payment for “TESC – Biofence” will be made at the contract unit price per linear foot as stated in the Schedule of Unit Prices and shall be full compensation for furnishing all labor, equipment, materials and tools necessary to complete the installation of the biofence as detailed on the drawings or as directed by the Engineer and specified herein. The unit price shall include all maintenance, the removal of biofence, and restoration of the area at the completion of the work

June 14, 2019

Horizontal Silt Fence

Photo: David Jenkins

Walking around South Congress district south of downtown Austin, I discovered a new best management practice-horizontal silt fence. This makes access to the work area so much easier than if vertical silt fence was used. Fortunately no rain in the near future.

March 8, 2019

Curb Inlet Protection

According to the Minnesota Stormwater Manual:

“Inlet protection devices intercept and/or filter sediment before it can be transported from a site into the storm drain system and discharged into a lake, river, stream, wetland, or other waterbody.

These devices also keep sediment from filling or clogging storm drain pipes, ditches, and downgradient sediment traps or ponds.

Inlet protection may also include placement of a barrier to create a bypass of an inlet transferring flow downstream to a sediment trap, basin, or other inlet discharging to a non-critical area.”

Nothing wrong with sediment control BMPs, as they are necessary tools in an effective erosion and sediment control system.  However, these do not “filter” sediment. 

When properly installed, these allow for ponding of water which allows larger sediment to settle out, keeping it out of the storm system.  This is a good thing, but doesn’t necessarily prevent water quality non-compliance.   

I do like this statement in the manual : “Caution: To the extent feasible, erosion prevention practices such as stabilization are preferred to sediment control practices.”

In my world, where we have to meet a turbidity effluent limit of 25 NTUs, stabilization and stormwater management are the primary methods used to meet strict turbidity limits.  

March 1, 2019

Managing Construction Projects to Prevent Sediment Trackout

I originally submitted this abstract for the 2019 IECA Denver conference . It was not accepted as a presentation but as an article in the October 2018 edition “Environmental Connection Magazine”.

Abstract
Sediment tracking from construction sites onto public roads and highways is a continual source or frustration for both regulators and contractors. The standard best management practices (BMPs) available, such as stabilized construction entrances and sweepers, often don’t work at all and, at best, only reduce total sediment by 30-50% which is inadequate for preventing water quality violations. In addition to water quality problems, sediment tracking onto roadways can generate dust, which may violate clean air standards and cause unsafe conditions, especially on highways.
This paper will discuss BMPs, methods, and procedures, which can be used by contractors to prevent sediment from being tracked onto roadways in the first place. In addition, ways to significantly reduce sediment loss will be presented. Some of these methods include:

• Passive tire baths
• Various tire washes
• Keeping vehicles of dirt
• Vacuum vs. mechanical sweepers
• Road washing
• Contract specifications

Each method will be discussed with pros and cons, design information and contract specifications.

The full magazine can be found at:
Environmental Connection, October/November 2018, Volume 13, Issue 4.

The article is attached below.

February 23, 2019

More Clean Water Diversion Best Management Practices

This shows several simple water diversion berms in action during a heavy rain. While the construction project is complete and the grass has grown, you can see how they prevented erosion during the project when bare dirt was exposed to rain.

January 14, 2019

Bonded Fiber Matrix BFM Needs to Cure Before it Rains

Bonded fiber matrix (BFM) needs to dry for 24 to 36 hours before it rains or else it can start to wash off.

December 2, 2018

Construction Erosion Inspection Hog Fuel Mulch Prevents Fugitive Dust

You are hauling dirt on a dry day and the dust is flying.
The water truck driver’s head is about to explode trying to keep up with the dust control.
Save yourself a Labor and Industries claim!
Use ground up vegetation (hog fuel)! Don’t haul it to the landfill.

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