cut and paste directly from WDFW webiste: (emphasis mine)
"An HPA must be obtained from WDFW before work is conducted that uses, obstructs, diverts, or changes the natural flow or bed of state waters.
The conditions of an HPA are designed to protect fish, shellfish, and their habitat. Regulated activities include bank protection, dredging, fish passage corrections, flow control structures, overwater structures and pilings, habitat and shoreline modifications, and other activities that affect waters of the state.
WDFW issues approximately 4,000 HPAs annually that cover projects throughout fresh and marine waters of the state."
....
"HPA application fees were adopted by the Washington legislature in 2012 (RCW 77.55.321), and went into effect July 10, 2012. Most HPA applications require payment of a $150 application fee before DFW can process it.
There are some exemptions from the application fee, including forest practices, projects on farm and agricultural lands, mineral prospecting and mining, pamphlet HPAs, and HPAs issued under interagency agreements. The HPA fee will not apply to minor project modifications (e.g., to work windows), but will apply to applicant-requested modifications that result in the issuance of a new HPA, provided the original HPA was subject to the application fee. DFW has established a template contract/agreement that higher volume customers can use to apply a billing account to pay for HPA fees."
http://wdfw.wa.gov/licensing/hpa/#fees.