Chapter 173-501 WAC

On May 27, 2020 Ecology adopted amendments to Chapter 173-501 WAC, Instream Resources Protection Program - Nooksack Water Resource Inventory Area (WRIA) 1 to meet the requirements in RCW 90.94.020.

The rule amendments updated and added to water management regulations in WRIA 1 to meet the requirements in RCW 90.94.020. The purpose of the rulemaking was to amend the rule to:

  • Add flexibility for projects that retime high flows for instream resource benefits.
  • Establish domestic permit-exempt groundwater withdrawal limits for new users.
  • Make minor technical corrections. 

We developed technical findings and documentation to support the rulemaking. This includes supporting documentation for the rule that estimates consumptive use of new domestic permit-exempt wells in the WRIA for the next 20 years, and projects and actions to offset potential impacts to instream flows associated with the permit-exempt domestic water use. The supporting documentation also includes an evaluation for Net Ecological Benefit in the watershed to meet the requirements of RCW 90.94.020.
RCW 90.94.020 directed Ecology to begin rulemaking to meet the requirements of the statute if a locally-approved watershed plan update was not adopted by Ecology by January 31, 2019. A plan update was not submitted to Ecology for review and adoption, so Ecology was required to proceed with the rulemaking.
RCW 90.94.020 requires us to adopt rules for WRIA 1 by August 1, 2020.

Rulemaking timeline


Announcement phase (CR-101)

Filing date:
Feb. 5, 2019

Announcement documents

Rule development phase

Feb. 5, 2019 - Nov. 2019

Public input & involvement

We developed preliminary draft language for the rule amendment and a rule supporting document for Chapter 173-501 WAC:

Informal Comments

The informal comment period on the preliminary draft documents is now closed. We accepted informal comments from Apr. 8, to May 10, 2019 via our online comment system and by mail. The feedback we received on the preliminary draft documents will be used as we develop a rule amendment proposal.

Open house

The preliminary draft was discussed at three public open houses. The public open houses were an opportunity for informal conversations about the preliminary draft. Please note, we did not take oral comments during these open houses.
The following public open houses were scheduled:
Ferndale Library
2125 Main Street, Ferndale, WA 98248
1:00 – 3:00 p.m.
Monday, Apr. 22, 2019 
Lynden Library
216 4th Street, Lynden, WA 98264
6:00 – 8:00 p.m.
Monday, Apr. 22, 2019 
Ecology’s Padilla Bay Reserve
10441 Bayview Edison Rd, Mt Vernon, WA 98273
9:30 – 11:30 a.m.
Tuesday, Apr. 23, 2019

​If you would like to be notified about the next steps in this rulemaking please sign up for the Water Resources Program ListServ.

Rule proposal phase (CR-102)

Filing date:
Nov. 19, 2019

Rule proposal documents:

Comment period

We accepted comments on the proposed rule from November 19, 2019 through January 17, 2020.
The comments received are available here

Public Hearings:
Three public hearings were held in January 2020. More information on the hearings is below.

January 7, 2020
6:00 p.m.
Fairhaven Middle School, Commons Area
110 Parkridge Rd, Bellingham, WA 98225
January 8, 2020
3:00 p.m.
Lynden Middle School, Commons Area
8750 Line Rd, Lynden, WA 98264
January 9, 2020
10:00 a.m.
Ecology’s Padilla Bay Reserve
10441 Bayview Edison Rd, Mt. Vernon, WA 98273

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To request ADA accommodation for disabilities, or printed materials in a format for the visually impaired, contact Ecology's ADA Coordinator by email at, or call 360-407-6831. People with impaired hearing may call Washington Relay Service at 711. People with speech disability may call TTY at 877-833-6341.