SwpppDraft

Washington SWPPP requirements (2026)

Can I write my own SWPPP in Washington?

Washington accepts a SWPPP prepared by the operator — no professional licence is required to write it. Basis: Ecology CSWGP (2026-01-01 – 2030-12-31), S9 versus S4.B.

Source: Ecology CSWGP (2026-01-01 – 2030-12-31), S9 versus S4.BVerified

Who may prepare the plan in Washington

The Permittee must prepare and properly implement an adequate Stormwater Pollution Prevention Plan (SWPPP)…

Ecology CSWGP (2026-01-01 – 2030-12-31), S9 versus S4.B — verbatim permit text, read 2026-08-03

Our reading of Ecology CSWGP (2026-01-01 – 2030-12-31), S9 versus S4.B:Washington requires the permittee to prepare the SWPPP; the Certified Erosion and Sediment Control Lead requirement applies to site inspections.

How Washington differs from the federal baseline

States with no NPDES authorisation of their own run on the EPA 2022 Construction General Permit, whose "qualified person" definition is a knowledge and skill threshold that the operator's own staff can meet — it names no licence. Washington's own permit adds no licence, exam or credential above that baseline, so there is nothing further to satisfy here.

Federal baseline: EPA 2022 CGP (no state NPDES authorisation), Appendix A definitions.

What that means for a 1–5 acre site

Below one disturbed acre, federal construction general permit coverage is usually not required at all unless the site is part of a larger common plan of development. Check whether you need a SWPPP before you pay for one.

Above five disturbed acres you are outside the 1–5 acre range this tool was built for. Several states change their preparer requirements above five acres, so re-read your state permit before relying on a self-prepared plan.

County and city rules are not covered here. This page answers the state-level question only; a local authority can require more, and that is for you to check.

Washington SWPPP questions

Can I write my own SWPPP in Washington?
Washington accepts a SWPPP prepared by the operator — no professional licence is required to write it.
Does Washington's permit name any preparer qualification at all?
Washington requires the permittee to prepare the SWPPP; the Certified Erosion and Sediment Control Lead requirement applies to site inspections. The clause is Ecology CSWGP (2026-01-01 – 2030-12-31), S9 versus S4.B, read on 2026-08-03.
Which acreage counts — the whole site or the disturbed part?
Disturbed area is what these clauses measure, and it is what the questionnaire asks for — a 40-acre parcel with 1.5 disturbed acres is a 1.5-acre project for this purpose. Total site area is asked for separately and does not decide the answer.
Does Washington run its own permit, or the federal one?
On its own. Washington issues the construction general permit or implementing regulation this page was read from — Ecology CSWGP (2026-01-01 – 2030-12-31), S9 versus S4.B. The federal permit still sets what a SWPPP has to contain; the state document is what decides who may write it here.
What does a SWPPP cost in Washington?
A consultant-prepared SWPPP for a small site is commonly quoted at around $497 — a market figure inherited from our own competitor review, which we have not re-verified. SwpppDraft intends to charge $99 for the plan and $149 with the forms pack, and is not open for sale yet, so nothing can be bought here today. Washington's permit does not require you to buy anything in order to prepare the plan — what it costs you is the time to answer questions about your own site.
Do county or city rules apply on top of this?
They can, and this page does not cover them. The scan behind it answered the state-level question only, so a county or municipality in Washington may require more — a stamped plan, a local permit, or a different form — even where the state permit does not. Ask the authority that will receive your paperwork before you write the plan, not after.

Build a SWPPP for a site in Washington
The questionnaire and the generator run in your browser and produce a watermarked draft. Checkout is not open, so nothing can be charged.

The documents, one at a time

Related questions

Source and verification

Ecology CSWGP (2026-01-01 – 2030-12-31), S9 versus S4.B. Read the source document State-law information on this page was verified on 2026-08-03. County and city rules are not covered. Washington in context:its row in the 50-state table.

What we are, and what stays your responsibility

  1. SwpppDraft is a document generation tool. It does not provide engineering services, legal services, or compliance consulting, and no engineer or attorney reviews what it produces.
  2. Everything in the document is built from the site facts you enter. Checking that those facts are right, and that the resulting plan fits your project, is yours to do.
  3. We do not file anything on your behalf, we do not certify or endorse your compliance, and we accept no liability for what happens when you use the document.
  4. State-level requirements carry the date we verified them. County and city rules are not covered — some local jurisdictions require a licensed preparer even where the state does not, and you have to check that yourself.
  5. When the product opens, our total liability will be capped at the amount you paid us. Today that amount is zero, because nothing is for sale.