Comprehensive Plan GMA Compliance

The Washington State Growth Management Act (GMA) requires local governments to include a housing element in their comprehensive plan that identifies sufficient land capacity and zoning to accommodate housing for all income segments. Affordable Housing is defined in the GMA as housing that is affordable to those earning at or below 80% of the Area Median Income (AMI). STEP is an acronym for several types of housing, including: shelters, transitional housing, emergency housing, and permanent supportive housing. This article will provide more information on these housing types and the requirements in State law for cities pertaining to providing for this housing.

What is AMI?

Affordable housing is often characterized based on percentages of the Area Median Income, or AMI. AMI is the midpoint of a specific area’s income distribution and is calculated by the U.S. Department of Housing and Urban Development (HUD) each year. The HUD calculation determines median income for a four-person household based on the Census Bureau’s American Community Survey (ACS) data and is adjusted for inflation based on projected per capita wage growth. The geographic area is determined by HUD’s Metro FMR Area definitions.

Mercer Island is part of the Seattle-Bellevue, WA Metro FMR Area, which contains King and Snohomish Counties. The 2025 AMI for the Seattle-Bellevue FMR Area is $157,100. AMI can be adjusted based on household size and income level. Below is a table from A Regional Coalition for Housing (ARCH) with 2025 AMI levels based on household size.

Mercer Island’s Housing Needs

Under the GMA, cities are required to plan for housing needs across income levels. Cities must provide capacity for the identified housing units at each affordability level AND provide "adequate provisions," such as regulations and incentives, to help make this housing available. Housing needs, also referred to as "affordable housing targets," were identified statewide by the Department of Commerce, broken out by county. Counties then allocated housing needs to cities. Mercer Island’s housing needs, as assigned by King County, are shown below. Mercer Island has a total housing target of 1,239 units, of which 1,211 units are affordable housing units. In addition, 237 Emergency Housing beds are needed.

Extremely Low-Income Housing (0-30% AMI)

Mercer Island’s affordable housing targets include 517 units of “extremely low-income” or 0-30% AMI housing units. As shown in the chart above, this housing is for individuals earning less than $32,991 or a family of four earning less than $47,130. These 517 units are further categorized as Permanent Supportive Housing or Other Extremely Low-Income Housing.

Permanent Supportive Housing

178 of the 517 extremely low-income units must be designated as Permanent Supportive Housing or PSH. PSH is defined in the GMA as leased, long-term housing that includes support services (on- or off-site) and is designed to support persons with complex behavioral or physical health conditions and who are experiencing or at imminent risk of homelessness. This housing is intended to be “low barrier,” meaning it utilizes admissions practices that are less rigorous than typical for other subsidized or unsubsidized rental housing, especially related to “rental history, criminal history, and personal behaviors.” RCW 36.70A.030(33). The City must allow this housing in zones that permit residential uses and/or hotels. RCW 35A.21.430.

Other Extremely Low-Income Housing

The remaining 339 extremely low-income units constitute leased, long-term housing for individuals or families that meet the extremely low-income limits (30% AMI or below). This housing does not include support services. Eligibility for this housing can include seniors or people with disabilities on a fixed income as well as people who simply earn a low income. For example, a single parent with one child at home, working full time and earning minimum wage, would fall into this income level.

Other Affordable Housing

Mercer Island’s remaining affordable housing targets correspond to the Very Low-Income (30-50% AMI), Low-Income (50-80% AMI) and Moderate-Income (80-100% AMI) affordability levels. In total, the City must plan to accommodate 694 units across these affordability levels. The City’s consultant, Community Attributes, drafted the 2026 Land Capacity Analysis (LCA) showing that these housing needs can be addressed by unsubsidized, market-rate development when additional development capacity is added to the City.

The City Council has directed a phased approach to adding development capacity, with the Phase 1 upzones focused in and around the Town Center. The LCA shows that the planned upzones are sufficient to provide adequate capacity for the required affordable housing units between 30%-100% AMI.

Emergency Housing and Emergency Shelters

Emergency housing is temporary indoor accommodations for individuals or families who are homeless or at imminent risk of becoming homeless, and it may or may not require a lease or occupancy agreement. RCW 36.70A.030(15). Emergency shelters provide temporary shelter for individuals or families who are currently homeless, may not require a lease or occupancy agreement, and include day and warming centers that do not provide overnight accommodations. RCW 36.70A.030(16).

The City must allow these housing types in zones that allow hotels. RCW 35A.21.430. In addition, the City must provide adequate land capacity to accommodate the 237-bed target for emergency housing and shelters. RCW 36.70A.115.

Emergency housing and emergency shelters are currently regulated through interim regulations (Ordinance No. 26-02). These regulations will need to be replaced with permanent regulations to maintain compliance with state law. The Growth Management Hearings’ Board (“Board”) found the City’s emergency housing regulations in compliance with the GMA. However, recent legislation requires the City to amend these provisions related to spacing and operational requirements. This will be addressed as a part of the effort to comply with the Board's order.

Regulating Affordable, Permanent Supportive and Emergency Housing

Affordable Housing

PSH and other affordable housing are afforded the protections provided in Chapter 36.130. RCW, Affordable Housing Development, which applies to housing that is affordable up to 80% AMI. This means that development regulations applicable to PSH and other affordable housing are regulated by Chapter 36.130 RCW, and cities may not impose requirements that are different than the requirements imposed on housing generally.

Some exceptions to this apply such that conditions may be imposed on affordable housing developments, including PSH, as a prerequisite to receiving optional assistance such as tax benefits, subsidy funds, sale or lease of public property, or eligibility for optional housing incentive programs such as density bonuses, height and bulk bonuses, fee waiver, parking reduction, or expedited permitting. RCW 36.130.020(3), RCW 36.70A.540. If a developer, however, chooses not to participate in an optional program, a city may not condition approval of a permit that is otherwise consistent with development standards. RCW 36.70A.540(1)(c).

Emergency housing and shelters are not “affordable housing,” and are not subject to the protections of Chapter 36.130 RCW. However, recently adopted legislation, HB 2266, limits the regulatory requirements that local jurisdictions may enact. As mentioned above, this housing must be permitted in zones that allow hotels. Additionally, jurisdictions may not require any standards, conditions, or requirements for this housing that are more restrictive than those required for other types of lodging or residential development in the zone.

Occupancy Standards

Occupancy standards regulate who is permitted to live in a specific type of housing. All of the housing types discussed in this memo are subject to Federal and State fair housing and anti-discrimination laws. These laws protect certain groups, generally prohibit discrimination, and apply to the regulation of occupancy. In addition, as outlined above, State law provides that affordable housing must be regulated the same as housing developments generally. RCW 36.130.020. Thus, the City has very little authority to regulate occupancy of PSH or other types of affordable housing.

Additional Resources

Department of Commerce Guidance

• Updating Housing Elements
• STEP Housing
• STEP Housing Definitions

Relevant Legislation

• HB 1220
• HB 2266

On April 29, the Planning Commission will begin review of amendments to the Comprehensive Plan and development regulations as well as a proposed Station Subarea Plan related to GMA Compliance Project. At this meeting, Staff will be briefing the Planning Commission on the Station Subarea Plan Goals and Policies and the schedule for the legislative review of necessary amendments to the Comprehensive Plan and Development Regulations. The City has published two planning commission bills for consideration:

• Planning Commission Bill 26-02: Planning Commission Legislative Review Process
  • Exhibit 1: Planning Commission Legislative Review Schedule
• Planning Commission Bill 26-03: Briefing on Station Subarea Plan Goals and Policies
  • Exhibit 1: Station Subarea Plan

The Planning Commission legislative review schedule is as follows:

April 29: Station Subarea Plan

May 6: Comprehensive Plan Amendments

May 13: Development Code Amendments

May 20: Development Code Amendments

May 27: Comprehensive Plan Amendments

June 3: Public Hearing

June 10: Planning Commission Recommendation

June 16: Presentation of Planning Commission Recommendations to City Council

The Planning Commission public meetings will be held at 6:00pm, in the Slater Room at the Mercer Island Community and Event Center, located at 8236 SE 24th Street, Mercer Island. Information to attend virtually can be found using the "Meeting Details" links on the Planning Commission Meetings page.

At its regular meeting on April 21, 2026, the City Council provided final direction on the strategy to achieve GMA Compliance. City Council gave the following direction:

1. Set the inclusionary zoning requirements at 10% of units to be affordable at 50% AMI when drafting code amendments to comply with the GMHB Order.
2. Prohibit adult entertainment and warehousing in the TC-8 subarea when drafting code amendments to comply with the GMHB Order.
3. Include policy direction in the Station Subarea Plan to review the requirements for average daylight plane, major site features, and major façade modulation during Station Subarea Plan Phase 2.

The City Council also directed the Planning Commission to initiate legislative review of the required amendments to the Comprehensive Plan and Development Code, alongside a proposed Station Subarea Plan. The Planning Commission review process begins on April 29 and is scheduled to conclude by June 10 with a formal recommendation to the City Council. The Commission will also hold a public hearing on the proposed amendments on June 3. Following this, the City Council will review the Commission’s recommendations and adopt the necessary ordinances during its meetings throughout June and July. This timeline ensures the City meets the mandatory Growth Management Hearings Board compliance deadline of July 31, 2026.

The Planning Commission legislative review schedule is as follows:

April 29: Station Subarea Plan

May 6: Comprehensive Plan Amendments

May 13: Development Code Amendments

May 20: Development Code Amendments

May 27: Comprehensive Plan Amendments

June 3: Public Hearing

June 10: Planning Commission Recommendation

June 16: Presentation of Planning Commission Recommendations to City Council

The Planning Commission public meetings will be held at 6:00pm, in the Slater Room at the Mercer Island Community and Event Center, located at 8236 SE 24th Street, Mercer Island. Information to attend virtually can be found using the "Meeting Details" links on the Planning Commission Meetings page.

On April 21, the City Council will receive the next briefing on the Growth Management Hearings Board (GMHB) Order. Staff will be requesting City Council direction on development code amendments and the Planning Commission legislative review schedule. The City has published two agenda bills for consideration:

• Agenda Bill 6911: GMA Compliance – Legislative Review Process
  • Exhibit 1: Planning Commission Legislative Review Schedule
• Agenda Bill 6909: GMA Compliance – Policy Direction on Development Code Amendments
  • Exhibit 1: Inclusionary Zoning and Fee in Lieu of Affordable Housing Policy Brief
  • Exhibit 2: Town Center Zoning Amendments Policy Brief
  • Exhibit 3: Town Center Design Standards Policy Brief

Please see the City of Mercer Island April 21, 2026, meeting webpage for information on how to attend in person or virtually, and how to register to make a public comment.

The City of Mercer Island held a virtual webinar on the Growth Management Hearings Board (GMHB) Order and the Comprehensive Plan GMA Compliance Project on the evening of March 10, 2026. The virtual webinar was an opportunity for the City to hear from residents about questions or comments regarding the Comprehensive Plan GMA Compliance Project. Staff prepared responses to the submitted questions in the Public Questions Matrix.

More information on the the virtual webinar is available via the Community Information Session - Recording and Slides article.

The City of Mercer Island held a virtual webinar on the Growth Management Hearings Board (GMHB) Order and the Comprehensive Plan GMA Compliance Project on the evening of March 10, 2026. The recording is available below or through the City Council Community Information Session on GMHB Order webpage. The comments and questions received will be responded to and posted online shortly.

The next opportunity for public input will be at the 5pm March 17, 2026, City Council Meeting located in the Slater Room in the Mercer Island Community & Event Center. The meeting can be attended in person or virtually - more details are available on the City Council webpage.

The slide deck used in the presentation is available for viewing: Community Information Session Presentation.

The table provided on Slide 18 of the Community Information Session slide deck was truncated for brevity. The full table, below, compares projected housing needs to capacity as presented at the February 17, 2026, City Council meeting (AB6865).

Slide 18: Land Capacity Analysis Table

Join us for a virtual webinar on the Growth Management Hearings Board (GMHB) Order and the Comprehensive Plan GMA Compliance Project from 6:00 to 7:00 pm on Tuesday, March 10, 2026. Additional details and registration are available through the link below:

Community Information Session - GMHB Order

Following the appeal of the City's 2024 Comprehensive Plan Periodic Update, the Growth Management Hearings Board (GMHB) issued a Final Decision and Order (GMHB Order) with a compliance deadline of July 31, 2026. The GMHB Order requires the City to address four issues:

1. Land Capacity Analysis: Identify residential land capacity at each housing affordability level and close any identified gaps.
2. Adequate Provisions: Adopt incentives, mandatory provisions, and planned actions that will increase the supply of affordable housing.
3. Station Area Subarea Plan: Adopt a subarea plan for the area around the transit station.
4. Anti-Displacement Measures: Adopt measures to address the potential displacement that can occur with changes in zoning and redevelopment of lower-cost housing.

Updating the Comprehensive Plan to comply with the GMHB Order will affect Mercer Island in numerous ways. Attend the Information Session Webinar to learn more about the GMHB Order and the City's plans to comply by the July deadline.

On February 17, the City Council continued discussions on the strategy to comply with the Growth Management Hearings Board (GMHB) Order, issued in August 2025, which requires the City of Mercer Island to update its Comprehensive Plan and Development regulations by the end of July. City staff and consultants provided a detailed presentation that can be viewed here.

The GMHB Order requires the City to plan for and accommodate housing across a range of affordability levels by creating sufficient land capacity and adopting policies, incentives, and subsidies to support this development. Additionally, the City must adopt a subarea plan for the area surrounding the Sound Transit light rail station and adopt anti-displacement measures aimed at helping tenants stay in the community as lower cost housing is redeveloped.

At the meeting, the City Council approved a phased approach to compliance with the GMHB order (AB 6865). The first phase establishes a transit station subarea and applies required upzones and additional development capacity, to be completed by July 31, 2026. This first phase of work is shown in the map below in dark purple as the “Phase 1 Subarea.” The second phase, which would commence after July 31, 2026, would apply upzones and resulting development capacity increases to the rest of the station area to comply with state requirements implemented by HB 1491 (the Transit Oriented Development (TOD) bill) by December 31, 2029. This second phase of work is shown in the map below in violet as the “Phase 2 Subarea.”

Preliminary Modified Station Area and GMA Compliance Phase 1 and Phase 2 Subareas.

Phase 1 would include upzones to the Town Center and adjacent multi-family zones, increasing maximum allowable building heights to approximately eight stories and six stories, respectively. The land capacity analysis projects a resulting increase in development capacity of 1,031 additional housing units that serve a variety of affordability levels. The City’s analysis also shows that increasing development capacity does not adequately address housing needs for the extremely low-income affordability level (0-30% of area median income). An “affordability gap” of 510 extremely low-income units remains and must be addressed through additional policies, incentives, and subsidies. The City Council has directed staff to continue developing strategies to address this gap.

The City Council also reviewed a draft Station Area Boundary (shown in the map below in dark blue), which includes the area within a half mile walk from the light rail station entrances. The GMHB Order requires the City to adopt a subarea plan for this area, which will include goals and policies related to housing, transportation, economic development, infrastructure, and other issues. This plan will help guide work on the Phase 2 rezones as well as future growth and development in the Station Area.

The City Council is seeking public feedback on the proposed Station Area Boundary through March 13, 2026. Please submit comments via the City’s Let’s Talk page.

Preliminary Modified Station Area Boundary

The public is invited to attend a Community Information Session Webinar on Tuesday, March 10 from 6:00 to 7:00 pm to learn more about the appeal of the City’s Comprehensive Plan, the GMHB Order, and the City’s plan to achieve compliance. Register for the webinar here.

To stay informed as the project progresses, visit the City’s Comprehensive Plan GMA Compliance webpage for periodic updates.

On February 17, 2026, the City Council will receive the next briefing on the Growth Management Hearings Board (GMHB) Order, and the City's compliance strategy. The City has published three agenda bills for consideration:

• AB 6865 and Exhibit 1: Compliance with Growth Management Hearings Board Final Decision and Order Related to the City of Mercer Island Periodic Update to the Comprehensive Plan
• AB 6866 and Exhibit 1: GMA Compliance Public Engagement Plan
• AB 6871 and Exhibit 1: Legislative Review Alternatives to Help City Meet GMHB Order Compliance Deadline

Please see the City of Mercer Island February 17, 2026, meeting webpage for information on how to attend in person or virtually, and how to register to make a public comment.