Sheetflow Erosion Control Erosion Control for the CESCL

September 24, 2020

Biodegradable Erosion Control BMPs: Burlap Fence Compost Sock

Video: David Jenkins

Biodegradable Erosion Control BMPs: Burlap Fence Compost Sock

My goal was 100% biodegradable BMPs on this habitat restoration project. In this video I show the burlap silt fence and the compost socks.

September 8, 2020

Biodegradable Wattles

I wrote this biodegradable wattles specification for a riverbank habitat restoration project.

I wrote the last three sentences for this particular project, which has a 2:1 slope above an intertidal river. We will place 12 inches of compost before installing native plants this winter; without the wattles, wet compost will slide to the base of the slope.

BIODEGRADABLE WATTLES

  1. Wattles shall consist of 100% biodegradable straw, coir, excelsior or compost encased in 100% biodegradable fabric or mesh.
  2.  Wattles shall be a minimum of 8 inches in diameter free of cuts tears and damage.
  3. The installation of straw wattles shall be per WSDOT Standard Plan I-30.30-00 “Wattle Installation on Slope”.
  4. Wattles shall be staked in place using wooden stakes a minimum of 16 inches long.  The stakes shall be cut flush with the top of the wattles.
  5. Wattles shall be installed on the Site 25 slope above +12 elevation.
  6. Wattles shall be installed in two rows across the slope parallel to the 12 + elevation. 
  7. Rows shall be approximately 7 feet above the +12 elevation and 7 feet below the top of the slope.

April 20, 2020

Environmentally Friendly, Biodegradable, Re-usable, and Recyclable Erosion and Sediment Control BMPs

I wrote this article for the April-May 2020 “Environmental Connections” magazine of the International Erosion Control Assn.  It starts on page 26.

Environmentally Friendly, Biodegradable, Re-usable, and Recyclable Erosion and Sediment Control BMPs

David Jenkins, CPESC

Erosion Control/Stormwater Engineer, Port of Seattle

Background

We have all seen silt fence left in place years after a project is completed, heard of birds and reptiles trapped in erosion blanket netting even after the straw and coconut mulch has biodegraded (1), and know of catch basin inserts and silt fence landfilled at the end of a project.

In 2015, the Port of Seattle (Port) rebuilt the center runway at Sea-Tac International Airport.  Silt fence was installed on the project perimeter-a total of nearly four miles.  Recyclers would not take the used fence and it ended up in a landfill. (2)

The Washington State Department of Transportation (WSDOT) keeps records of the total planned quantity of materials used on projects. From February 1, 2000 to February 1, 2020, the total planned quantity of silt fence used on WSDOT projects was 1,826,160 linear feet, or about 345 miles. Installed on both sides of Interstate 5, that quantity would run from Seattle, Washington to Portland, Oregon.  Based on my experience, the silt fence fabric likely ended up in a landfill or was left in place. (3)

The following are some means, methods, procedures and best management practices available to reduce the overall environmental impact of your construction projects. (more…)

Download: Environmental Connections, April-May 2020

Plastic mesh from straw wattle, five years after installation. Photo: David Jenkins

September 27, 2020

Erosion Control Photos

Filed under: — Sheetflow @ 3:49 pm

All photos may be used for teaching and training purposes with attribution to: David Jenkins, sheetflow.com

Photos may not be used for commercial purposes without prior express permission from David Jenkins, sheetflow.com

January 16, 2020

Straw Blanket Netting

Photo: David Jenkins

I saw this straw blanket netting while hiking at Twanoh State Park. The access road had some erosion issues and straw blankets were installed to cover roadside cut slopes. This work was accomplished about 4 or 5 years ago. Notice that the straw is gone but the plastic netting remains. 100% biodegradable netting is the way to go.

January 10, 2020

Plastic Netting

I saw this plastic netting today while looking at site we will be working on this summer. The straw wattle was left over from a previous project, completed almost six years ago. The straw filler is almost completely degraded. The netting is partially degraded, but in places is too strong to tear apart with my fingers. We need more 100% biodegradable best management practices and less plastic netting.

Six year old straw wattle. Photo: David Jenkins
Close up of plastic netting. Photo: David Jenkins

December 25, 2019

Merry Christmas 2019

 

Merry Christmas 2019!  What do I do when I am on vacation?  Take videos of erosion control, of course!

Erosion control blanket was installed on this slope in southern Utah about 6 years ago. The biodegradable material has degraded. The photodegradable netting is still intact, seemingly just as strong as new. The slope is south-facing, the area gets over 300 days a year of sun; what’s the deal? How long will this stuff last in the environment? I only specify 100% biodegradable erosion control blankets; this is one reason why.

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.  I use it whenever I can leave it in place to degrade, like on habitat or wetland work. 

Biofence Specification

Materials
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
 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

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