Key results

The Urban Growth Indicator shows a steady share of total growth within urban growth areas in recent years. 

• The region increased annual housing production between 2011 through 2023. However, the percentage of total housing production inside urban growth areas decreased from almost 100 percent in 2014 to a low of 90 percent in 2018. 
• In general, counties within the Seattle region were most likely to have a higher percentage of total housing production inside urban growth areas. 
• Counties with less housing growth (for example, Mason and San Juan) were most likely to have the lowest percentage of their new housing within urban growth areas. 

Performance in the Urban Growth Indicator declined in most counties in 2017-2023 compared to 2011-2016. 

• Between these two time periods (2011-2016 and 2017-2023), three counties improved their percentage of growth in urban growth areas. Four counties decreased their percentage of growth in urban growth areas. 
• Three more counties declined slightly (a decrease of 5 percent or less) in performance in this indicator. 
• Across the region, there was a slight decline in average growth channeled into UGAs in 2017-2023 (91.7 percent each year, on average) relative to the baseline reporting period (2011-2016, 95.3 percent each year, on average). We conclude that this indicator is "Getting Worse" relative to the baseline reporting period. 

The Infill Development Indicator shows that cities and counties vary widely. 

• In general, more populated counties (for example, King and Jefferson) did not add as much impervious surfaces per new housing unit than other counties. This suggests that those counties were locations with high density infill development.
• There are some outlier counties that need further analyses. 
• We do not yet have data available to characterize a trend over time in this indicator. We conclude that this indicator has "No Trend" but will update this report as we gain more information. 

Housing diversity is increasing regionwide. 

• Multi-unit housing increased as percentage of all units produced. It went from a low of 41 percent in 2011 to a high of 73 percent in 2023. Most counties increased the percentage of multi-unit housing over this period (2011-2023). 
• Even smaller counties increased multi-unit housing as a share of all units. 
• Across the region, there was an increase in percentage of total housing production that is multi-unit in 2017-2023 (66 percent each year, on average) relative to the baseline reporting period (2011-2016, 53.7 percent each year on average). We conclude that this indicator is "Getting Better" relative to the baseline reporting period. 

What factors affect these Progress Indicators? 

High demand for new housing in rural areas.

• Recent increased demand affects the housing market in rural areas. This demand can be linked to: 
  • remote work arrangements, 
  • desire for second homes, 
  • desire for vacation rentals. 
• The cost of living in urban centers is also on the rise. This affects whether people choose to live in urban centers (if feasible) or move to rural areas.  

Limited legal tools or incentives to prevent rural housing development. 

• Counties have limited tools to prevent rural landowners from building new homes. New home construction also often benefits the county. For example, new housing can help increase property tax revenue and sales tax revenue. 
• Urban areas in some counties may also lack the infrastructure (for example, water and sewer) to accommodate more development. 

Local zoning laws affect how cities and counties can promote housing diversity and infill development. 

• Some cities and counties have taken steps to promote multi-unit housing such as 
  • upzoning and rezoning to allow more units, 
  • adopting multi-family unit tax exemptions, 
  • reducing on-site parking requirements, 
  • modifying design guidelines, and
  • offering density bonuses.  

What other actions can we take? 

• Support the Land Development and Cover Implementation Strategy
  • This strategy has a detailed framework of actions that can promote infill and redevelopment in urban growth areas.
  • This strategy also includes ways to build Puget Sound-wide support to prevent the conversion of key natural areas. 
• Cities and counties can adjust zoning and construction laws inside urban growth areas. 
  • See Washington State Department of Commerce's Guidance for Developing a Housing Action Plan for specific strategies and tools. 
• Cities and counties can adopt the new SEPA Infill Exemption for middle housing (the construction of various types of multi-unit housing) in cities and unincorporated urban growth areas. 
• Cities and counties can consider laws to limit the use of homes outside of the urban growth area as short-term rentals. 
• Cities and counties can collaborate with experts in other fields to find strategies that have many benefits to communities.
  • For example, cities and counties could fund efforts that move low-income housing outside of areas that might be at risk to increased flooding or significant weather events. 
• Community members can take part in their country's planning process to promote the protection of natural areas and working lands.