47-Sec 01 57 14 Erosion Control Blanket.pdf

EROSION CONTROL BLANKET

01 57 14-1

SECTION 01 57 14

PART 1 - GENERAL

1.01 SECTION DESCRIPTION

A. This Work shall consist of furnishing and placing a biodegradable erosion control blanket for use as a temporary control to establish seeded areas.

1.02 RELATED SECTIONS

A. Related Work Specified Elsewhere:

1. Section 31 11 00: Clearing and Grubbing

2. Section 32 93 02: Exterior Planting

PART 2 - PRODUCTS

2.01 MATERIALS

A. The erosion control blanket shall be a machine produced 100% biodegradable mat of 70% agricultural straw and 30% coconut fiber blend matrix with a functional longevity of approximately 18 months. The blanket shall be of consistent thickness with the straw and coconut fiber evenly distributed over the entire area of the mat. The blanket shall be covered on the top and bottom sides with 100% biodegradable woven natural organic fiber netting. The netting shall consist of machine directional strands formed from two intertwined yarns with cross directional strands interwoven through the twisted machine strands (commonly referred to as a Leno weave) to form an approximate 0.50 x1.00 inch mesh. The blanket shall be sewn together on 1.50 inch centers (50 stitches per roll width) with biodegradable thread.

B. The straw / coconut fiber erosion control blanket shall be SC150 BN as manufactured by North

American Green, or equivalent. The straw / coconut erosion control fiber blanket shall have the following properties:

Material Content:

Matrix: 70% Straw Fiber (0.35 lbs / sq. yd.)

30% Coconut Fiber (0.15 lbs / sq. yd.)

Netting: Top – Leno woven 100% Biodegradable organic jute fiber (9.3 lbs / 1,000 sq. ft.

approximate weight) Bottom - 100% Biodegradable organic jute fiber (7.7 lbs / 1,000 sq. ft. approximate weight)

Thread: Biodegradable

01 57 14-2

PART 3 - EXECUTION

3.01 SHIPPING & STORAGE

A. The erosion control blanket rolls shall be furnished with suitable wrapping for protection against moisture in a manner that protects them from the elements. If stored outdoors, they shall be elevated and protected with a waterproof cover. At no time shall the erosion control blanket be exposed to ultraviolet light for a period exceeding 14 days.

3.02 SITE PREPARATION

A. Prepare the seedbed by raking, seeding, and fertilizing

3.03 GEOTEXTILE PLACEMENT

A. Begin at the top of slope by anchoring the blanket in a 6” deep by 6” wide trench with approximately 12” of blanket extended beyond the up-slope portion of the trench. Anchor the blanket with a row of staples approximately 12” apart in the bottom of the trench. Backfill and compact the trench after stapling. Apply seed to the compacted soil and fold the remaining 12” portion of the blanket back over seed and compacted soil. Secure blanket over compacted soil with a row of staples spaced approximately 12” apart across the width of the blanket.

B. Roll the blankets down the slope. Blankets will unfold with appropriate side against the soil surface. All blankets must be securely fastened to soil surface by placing staples in appropriate locations as specified by the manufacturer.

C. The edges of parallel blankets must be stapled with approximately 3” overlap. To ensure proper seam alignment, place the edge of the overlapping blanket even with the colored seam stitch on the previously installed blanket.

D. Consecutive blankets spliced down the slope must be placed end over end (shingle style) with an approximate 3” overlap. Staple through overlapped area, approximately 12” apart across the entire blanket width.

*NOTE: In loose soil conditions, the use of staple lengths greater than 6” may be necessary to properly secure the blankets.

END OF SECTION