HomeMy WebLinkAboutERC Report RMC Title IV Docket 19B CAO_FINALDEPARTMENT OF COMMUNITY
AND ECONOMIC DEVELOPMENT
ERC Report 2025 Docket #19, Critical Areas Ordinance
ENVIRONMENTAL REVIEW COMMITTEE REPORT
ERC MEETING DATE: September 15, 2025
Project Name: 2025 Docket #19 Group B: D-235, Critical Areas Ordinance (CAO) Update
Project Number: LUA25-000284, ECF
Project Manager: Mariah Kerrihard, Associate Planner
Owner: City of Renton
Applicant: City of Renton
Contact: Matt Herrera, Planning Director; Angie Mathias, Long Range Planning Manager;
Paul Hintz, Redevelopment Manager; and Mariah Kerrihard, Associate Planner
Project Location: The docket item is citywide.
Project Summary: The applicant is requesting Environmental (SEPA) Review to review the following
non-project item:
D-235 Critical Areas Ordinance – The purpose of the proposed code review and
amendments is to update RMC 4-3-050, Critical Areas Regulations, aligning it with
the latest state law requirements and the best available science as mandated by
the Washington State Growth Management Act. The City is undertaking a non-
project legislative action to update its Critical Areas Ordinance (CAO). This update
reorganizes and clarifies the city’s development regulations for critical areas as
designated by the state.
Exist. Bldg. Area SF: N/A Proposed New Bldg. Area (footprint):
Proposed New Bldg. Area (gross):
N/A
N/A
Site Area: N/A Total Building Area GSF: N/A
STAFF
RECOMMENDATION:
Staff Recommends that the Environmental Review Committee issue a
Determination of Non-Significance (DNS).
PART ONE: PROJECT DESCRIPTION / BACKGROUND
D-235 Critical Areas Ordinance: In compliance with the Growth Management Act the city will amend the
Critical Areas Ordinance (RMC 4-3-050) pursuant to RCW 36.70A.130(1). The Growth Management Act (GMA)
requires all Washington cities and counties to periodically review and update their critical areas ordinances
every ten (10) years to reflect emerging science and adapting best practices. The proposed amendments are to
align the City’s regulations with state mandated requirements and “best available science” (BAS).
The Critical Areas Ordinance (CAO) is a non-project action intended to update the set of development
regulations for the protection of environmentally sensitive areas and to safeguard the public from natural
hazards. The ordinance applies to all designated “critical areas” as defined in Renton Municipal Code (RMC
4-11-030), which include wetlands, streams, lakes, geographically hazardous areas, fish and wildlife habitat
conservation areas, frequently flooded areas, and Wellhead Protection Areas found anywhere within city limits.
The proposed changes introduce channel migration zone (CMZ) regulations into the Critical Areas Ordinance,
incorporating language and mapping standards from the City’s Shoreline Master Program (SMP). This update
City of Renton Department of Community & Economic Development Environmental Review Committee Report
DOCKET #19, CRITICAL AREAS ORDINANCE LUA25-000284, ECF
Report of Tuesday, September 9, 2025 Page 2 of 3
ERC Report RMC Title IV Docket 19B CAO_FINALB
ensures the CAO recognizes and regulates the potential lateral movement of rivers and streams. These
requirements ensure consistency with city, county, and state policies.
The CAO is not intended to impede growth or development but to provide responsible guidelines that:
• Prevent increased discharge of hazardous substances, noise, or pollutants unless fully mitigated;
• Mandate project specific mitigation measures for any impacts or disturbances;
• Maintain robust safeguards for fish, wildlife, and habitat; and
• Require all new projects to comply with updated environmental standards and review procedures.
The draft includes updates in accordance with state law and best available science, along with reorganization,
and functional changes to certain requirements. The intent of these changes is to enhance environmental
protection, public safety, and regulatory clarity without impacting current land use patterns or expected growth.
The proposed amendments include the following:
• Updating terminology, clarifying document references, and ensuring current standards use best
available science (BAS).
• The inclusion of Channel Migration Zone regulations within the CAO from the Shoreline Master Program.
• Addition of maintenance, repair, and operation of existing public facilities as well as new trail
construction from critical area regulations in flood hazard zones and wellhead protection areas as
exempt activities that may be permitted within critical areas and associated buffers, provided these
activities use best practices and do not increase risk.
• Existing wetland buffer widths and replacement ratios will be adjusted according to best available
science (BAS).
PART TWO: ENVIRONMENTAL REVIEW
In compliance with RCW 43.21C.240, the following environmental (SEPA) review addresses only those project
impacts that are not adequately addressed under existing development standards and environmental
regulations.
A. Environmental Threshold Recommendation
Based on analysis of probable impacts from the proposal, staff recommends that the Responsible
Officials:
Issue a DNS with a 14-day Appeal Period.
B. Mitigation Measures
1. None
C. Exhibits
None.
D. Environmental Impacts
City of Renton Department of Community & Economic Development Environmental Review Committee Report
DOCKET #19, CRITICAL AREAS ORDINANCE LUA25-000284, ECF
Report of Tuesday, September 9, 2025 Page 3 of 3
ERC Report RMC Title IV Docket 19B CAO_FINALB
Enhanced buffer requirements and updated science-based regulations lead to improved preservation
of wetlands, streams, lakes, geographically hazardous areas, fish and wildlife habitat conservation
areas, frequently flooded areas, and wellhead protection areas. By updating regulations around
development and land use near critical areas the proposal may help maintain or improve aquatic and
terrestrial ecosystem health and support threatened or endangered species. Key changes regulate
development in areas prone to flooding, landslides, or erosion, thus reducing risk for people and
property. Regulations more effectively address current environmental threats and long-term
sustainability challenges. As a non-project action, the code update itself does not directly cause
physical impacts, though future projects reviewed under the ordinance may be influenced. There are no
environmental impacts that are anticipated to occur in conjunction with the proposal.
E. Comments of Reviewing Departments
The proposal has been circulated to City Department and Division Reviewers. Where applicable, their
comments have been incorporated into the text of this report and/or “Advisory Notes to Applicant.”
Copies of all Review Comments are contained in the Official File and may be attached to this
report.
The Environmental Determination decision will become final if the decision is not appealed within the 14-
day appeal period (RCW 43.21.C.075(3); WAC 197-11-680).
Environmental Determination Appeal Process: Appeals of the environmental determination must be filed
in writing together with the required fee to: Hearing Examiner, City of Renton, 1055 South Grady Way,
Renton, WA 98057, on or before 5:00 p.m. on September 29, 2025. RMC 4-8-110 governs appeals to the
Hearing Examiner and additional information regarding the appeal process may be obtained from the City
Clerk’s Office, Renton City Hall – 7th Floor, (425) 430-6510.