Wisconsin WisDOT Standard Specifications (within FDM) — Section 627

Effective with the December 2018 Letting 379 2019 Standard Spec ifications Section 627 Mulching

627.1Description

(1)This section describes furnishi ng, placing, and anchoring a mulch cover, usually in connection with

seeding the surfaces of the roadway.

627.2Materials

(1)Mulching material consists of straw or hay in an air-dry condition, wood excelsior fiber, wood chips, or

other suitable material of a similar nature that the engineer a pproves, and is substantially free of noxious weed seeds and objectionable foreign matter.

(2)If using tackifier, the departm ent will prequalify it before u se. Select tackifiers from the department's

erosion control prod uct acceptability list ( PAL). The contractor may obtai n a copy of the department's PAL and the prequalification procedur e for products not on the dep artment's PAL.

627.3Construction

627.3.1 General

(1)Unless directed otherwise, place the mulch on the specified ar ea within 2 days after completing the

seeding.

(2)The contractor shall not perform mulching during periods of ex cessively high winds that might preclude

proper mulch placement.

(3)Place the mulch loosely or open enough to allow some sunlight to penetrate and air to slowly circulate,

but thick enough to shade the gr ound, conserve soil moisture, a nd prevent or reduce erosion.

(4)Maintain the mulched areas and repair all areas damaged by win d, erosion, traffic, fire or other

causes. 627.3.2 Placing

(1)The contractor may perform the work as sp ecified in one of the following ways: Method A, Method B,

or Method C, or a combination o f the 3, unless a specific metho d is specified in the contract. 627.3.2.1 Method A, Netting

(1)Uniformly spread the mulching ma terial over the designated are as to a loose depth of 1/2 to 1 1/2

inches. Use a specific rate o f application; dependent on the character of the material, that results in a cover conforming to the requi rements specified above in 627.3.1 . Loosen or make fluffy the mulch material from compacted bales before spreading in place. Unless directed otherwise, begin mulching at the top of the slopes a nd proceed downward.

(2)Securely anchor straw or hay mulch by using engineer-approved netting anchored to the ground with

pegs or staples to prevent it fr om floating as the vegetation g rows. Instead of this anchorage, the contractor may secure mulch by heavy biodegradable twine fastened by pegs or staples to form a grid with 6 to 10 feet spacing.

(3)The contractor may use departmen t-approved erosion control mats, listed in the department's PAL,

instead of separately applying mulch and netting. 627.3.2.2 Method B, Tackifier

(1)Treat straw or hay with a tack ifier, blow from a machine, and uniformly deposit over designated areas

in one operation. Place straw o r hay uniformly over the area 1/2 to 1 inch deep, using 1/2 to 3 tons of mulch per acre. Mix and place tackifier according to the department's PAL. Within the above limits, the engineer will determine, on the job, the application rate of the mulch and the tackifier, and the engineer may vary the rates during mulching to produce the desi red results. Use an engineer- approved machine to place the mulc h that blows or ejects by con stant air stream a controlled quantity of mulch and applies a spray of tackifier to partially coat the straw or hay, sufficient to hold together and keep in place the deposited straw or hay. The contractor ma y apply the tackifier as an overspray in a separate operation after placing the straw or hay.

(2)Apply wood fiber, wood chips, or similar material with engineer-approved blowing machines, or other

engineer-approved methods, that p lace a controlled quantity of mulch uniformly over the area 1/2 to 1 1/2 inches deep. Treat areas receiving wood chip mulch, with one pound of available nitrogen per 1000 square feet before or after applying the chips.

(3)Throughout the process, feed the mulch material into the blowi ng machine to produce a constant and

uniform ejection from the disc harge spout, and operate in a pos ition to produce mulch of uniform depth and coverage.

Effective with the December 2018 Letting 380 2019 Standard Spec ifications 627.3.2.3 Method C, Crimping

(1)Spread the straw or hay mulch u niformly over the designated ar eas to a loose depth of 1/2 to 1 1/2

inches, using 1/2 to 3 tons of mul ch per acre, by blowing from a machine, as specified in Method B, or by other engineer-a pproved methods.

(2)Immediately after spreading, anchor the mulch in the soil by u sing a mulch crimper consisting of a

series of dull, flat discs with notched edges. Space the 20 inc h diameter discs at about 8 inch centers. Equip the crimper with a ballas t compartment to allow adjusting the weight for depth control.

(3)Impress the mulch into the soil 1 1/2 to 2 1/2 inches deep in one pass of the crim per. The department

will not allow mulch crimpers to operate on slopes so steep tha t damage to the mulch, seedbed, or soil occurs. Anchor the mulch on these areas by one of the following methods: Method A or Method B. Equip and operate tractors to minimize disturbing or displacing the soil. This process may require more than one pass of the crim per to ensure adequate anchoring of the mulch.

(4)The contractor shall not use Method C if it cannot impress the mulch to a minimum of 1 1/2 inch.

627.4Measurement

(1)The department will measure Mulching acceptably completed by the square yard or by the ton,

whichever the contract specifies.

(2)If measured by the square yard , the measured quantity equals t he number of square yards of surface

area that the contractor applied the mulch.

(3)If measured by the ton, the m easured quantity equals the numbe r of tons of mulch provided, placed,

and acceptably completed.

(4)Tackifiers or nitrogen used fo r treating mulch are incidental to the cost of the work.

627.5Payment

(1)The department will pay for measured quantities at the contrac t unit price under the following bid

items: ITEM NUMBER DESCRIPTION UNIT

627.0200 Mulching SY

05 Mulching TON

(2)Payment for Mulching is full comp ensation for providing materials, including tackif iers or nitrogen; for

all hauling, treating, placing, s preading, and an choring of the mulch material; and for maintaining the work and repairing all damaged areas.

(3)If the contractor opts to use department- approved erosion cont rol mats instead of separately applying

mulch and netting, the departmen t will pay for it at the contra ct unit price for Mulching only.

Effective with the December 2018 Letting 381 2019 Standard Spec ifications Section 628 Erosion Control

628.1Description

(1)This section describes providi ng erosion control mats, bale ch ecks or dikes, fences, screens, blankets,

and other erosion control devices.

(2)This section also describes cleaning sediment basins and mobil izations for erosion control.

628.2Materials

628.2.1 General 628.2.1.1 Acronyms

(1)Interpret acronyms used thr oughout this section as follows:

ECRM Class I, II, and IIIA erosion co ntrol revegetative mats. TRM Class III B, C, and D turf reinforcement mats. 628.2.1.2 Product Acceptability

(1)The department prequalifies sele cted erosion control products in the department's PAL. If the contract

specifies, furnish pr oducts of the class, type, and subject to the seasonal limitati ons the department's PAL designates. Before installing a product from the department's PAL , submit to the engineer a written copy of the manufacturer' s specifications for installin g that product on slopes, channels, shorelines, high wind locations , and next to live traffic lanes as applicable to the contract installation. Install products from the department's PAL conforming to those manufacturer's specifications. The department may specify modificati ons to the manufacturer's proc edures for individual materials here within 628.

(2)The department may sample and test products supplied in the fi eld to verify that they conform to the

department's PAL prequalification requirements . Provide samples as the engineer directs. 628.2.2 Erosion Mat

(1)The department must prequalify all erosion mat products before use. Furnish erosion mat products

from the department's PAL.

(2)The department's PAL identifies prequalified erosi on mat products by class and type . Use the required

class and type of erosion mat t he plans show or the engineer sp ecifies. The contractor may furnish any prequalified erosion mat p roduct of the class and type the plans show or that the engineer specifies.

(3)If using jute fabric for a Class II Type A erosion mat, use a woven fabric of a uni form open weave of

single jute yarn. Use a jute ya rn of loosely twisted constructi on with an average twist of not less than 1 1/2 turns per one inch. Ensure the average size of the warp and weft yarns are a pproximately the same. Furnish the woven fabric i n rolled strips. Submit a certi ficate of compliance certifying that the jute fabric erosion mat conforms to the following: - Is a minimum 48 inches wide with a tolerance of minus one inch. - Has 78 warp ends, +/- one for each 48 inches of width. Has 45 weft yarns, +/- 2, per linear yard of length. - Weighs 92 pounds per 100 square yards +/ - 10 percent, measure d under average atmospheric conditions. - Is non-toxic to vegetation. 628.2.3 Staples

(1)Furnish U-shaped staples, made of No. 11 or larger diameter steel wire, or other engineer-approved

material, are one to 2 inches wide, and not less than 6 inches long for firm soils and not less than 12 inches for loose soils. The contractor may use anchors the staple gun manufacturer recommends, either lighter gage staples or equivalent, for engineer-approve d staple gun systems. 628.2.4 Bales

(1)For bales, use straw, hay, or other engineer-approved material , in good condition, of the dimensions

the plans show. 628.2.5 Stakes

(1)Furnish wood or metal stakes of the dimensions the plans show.

628.2.6 Silt Fence 628.2.6.1 Geotextile

(1)Furnish one of the following geot extiles: woven or non-woven polyester, polypropylene, stabilized

nylon, polyethylene, or polyvinylidene chloride. For non-woven fabric the contractor may use needle punched, heat bonded, resin bonded, or combinations of all 3. S ubmit a certificate of compliance certifying that the geotextile conforms to the following:

Source: Wisconsin Standard Specifications for Highway and Structure Construction, 2019 Edition. Pages 388–389 of 601.

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626 Peat Humus

628 Erosion Control