Washington DOT hydroseeding & erosion-control specs.
WSDOT Section 8-01/8-02 defers seed species and rates to the project Contract, Plans, and Special Provisions — no fixed statewide roadside seed mix. Erosion-control materials are tightly gated through the WSDOT Qualified Products List.
Other state specs
Section 8-01 / 8-02 — Erosion Control & Roadside Planting (Standard Specifications M 41-10)
Deferred-mix state
Seed mix policy
Species and rates are deferred to the project Contract / Plans / Special Provisions — the Section 8-01/8-02 base spec has no fixed statewide roadside seed mix.
HECP / BFM application rate
Hydraulic Erosion Control Products (HECP / bonded fiber matrix) are applied at approximately 2,500–3,500 lb/acre depending on product type and slope; paper/cellulose-only fiber mulch is restricted on steeper, higher-risk slopes.
Soil binder / PAM rule
Soil binders and PAM must be on the WSDOT QPL; anionic linear (non-crosslinked) PAM is the accepted chemistry for erosion applications — cationic PAM is not accepted for water-contact use due to aquatic toxicity.
Approved / Qualified Products
WSDOT Qualified Products List — mulches, HECPs, tackifiers, and soil binders/PAM must be selected from it.
Portal: https://wsdot.wa.gov/publications/manuals/fulltext/M41-10/SS.pdf — verify manually; some DOT portals block automated access.
Summarized from the WSDOT standard specifications for reference only — verify against the current official spec and your project’s plans / special provisions before bidding or applying. Source: official specification.
Need this installed in Washington? Request a contractor match DOT & municipal contractors