Skip to main content

Future Annexation and Municipal Urban Growth Areas

Annexation Update

The Mill Creek City Council voted 6-1 at its October 13 meeting to approve a resolution authorizing the City Manager to pursue annexation of designated unincorporated areas within the City’s Municipal Urban Growth Area (MUGA).

The proposed first phase focuses on Mill Creek South, consisting of Blocks C, D, and H located south of the City’s existing boundaries. The area includes neighborhoods near 180th Street SE and 192nd Street SE, with boundaries generally extending east toward 35th Avenue SE and west toward the North Creek corridor. 

A Map of the potential Annexation areas of Mill Creek
Potential Mill Creek Annexation Subarea Map

Why Would the City Annex?

Increased stability of revenue sources
Annexation may help stabilize the City’s tax base by bringing areas that already rely on City services into the City’s boundaries, creating a more predictable and sustainable source of revenue to support police, parks, streets, and other services.

New opportunities to encourage commercial activity
By annexing nearby commercial corridors, the City could apply its own zoning, infrastructure planning, and economic development tools to support new businesses, reinvestment, and job growth in a way that complements the existing community.

Ability to influence the look and feel of gateway areas
Annexation allows the City to apply its development standards and design guidelines to key corridors leading into Mill Creek, so that buildings, signs, landscaping, and public spaces reflect the community’s desired character and create a consistent “front porch” to the city.

Opportunity to shape development around a future light rail station
Bringing areas that are near a future light rail station into the City gives the community a greater voice in how those properties grow and change, helping to support transit-oriented development, walkability, housing, and job choices that make the most of the regional investment in light rail.

What areas could the City of Mill Creek potentially annex?

The City of Mill Creek has currently divided the Municipal Urban Growth Area into multiple subareas to allow for more flexibility when it comes to annexation options.

What is a Municipal Urban Growth Area (MUGA)?

A Municipal Urban Growth Area (MUGA) is the portion of the Urban Growth Area that a city is expected to eventually annex and serve. It identifies where a city will focus future urban development, infrastructure, and services, ensuring growth occurs in areas planned for urban levels of housing, jobs, and public facilities.

Who determines the MUGA?

The County designates MUGAs in accordance with RCW 36.70A.110. According to RCW 36.70A.100, the designation of MUGAs must be coordinated between the county and cities.

What is the purpose of a MUGA?

The Washington State Growth Management Act requires Washington communities to direct growth into designated Urban Growth Areas (UGAs) where urban services can support it, while preserving rural and resource lands for non‑urban uses. Learn about the Growth Management Act here.

Timeline & City Council Discussions

  • October 13, 2026 – Council voted to authorize the City Manager to proceed with pursuing annexation of certain unincorporated areas within the City’s Municipal Urban Growth Areas.
  • July 28, 2026 – Consultants Rob Fenty (1961 Consulting) and Sarah Emmans (SME Consulting) provided key updates and scenario analysis for areas of potential annexation. Council gave guidance to staff about what scenarios to study more closely.
  • June 23, 2026 – Consultants Rob Fenty and Sarah Emmans presented Council with three proposed areas for consideration that would help narrow the Council’s desired direction for phase one of annexation. With new updated information related to infrastructure and a clearer direction for a path forward, Ms. Emman’s will then bring forward updated staffing assumptions and financial projections for this narrowed area of interest, which consists of Mill Creek East and some of Mill Creek South.
  • May 05, 2026 – Rob Fenty, 1961 Consulting, guided Council in an annexation discussion kickoff.
  • April 14, 2026 – Council voted to approve a contract with 1961 Consulting and a contract with SME Consulting for annexation feasibility work.
  • February 24, 2026 – Rob Fenty, 1961 Consulting, led Council and staff in the Strategic Planning Retreat, providing Council the opportunity to discuss pros and cons of two of the four Urban Growth Areas (UGAs), Martha Lake and Larch, and facilitated Council’s prioritization of the four potential annexation options.
  • February 10, 2026 – Rob Fenty, 1961 Consulting, led Council and staff in the Strategic Planning Retreat, developing a framework to use when considering potential annexation areas and providing Council the opportunity to discuss pros and cons of two of the four Urban Growth Areas (UGAs), Mill Creek East and Mill Creek South. Sarah Emmans, SME Consulting, provided additional information to Council about the UGAs. 
  • February 03, 2026 – Deputy City Manager Brock and consultant Sarah Emmans of SME Consulting LLC led a discussion about the Annexation Feasibility Study findings.
  • January 27, 2026 – Council approved an amendment to the contract with SME Consulting for the Annexation Feasibility Study.
  • December 09, 2025 – 1961 Consulting Partner Rob Fenty led a Study Session on the upcoming 2026 City Council Strategic Retreat, which will focus on the topic of potential annexation.

Search