The Cost of Growth on the Key Peninsula


Sara Thompson, KP News

The population in the Puget Sound region is projected to grow by 1.8 million by 2050, according to the Puget Sound Regional Council. The largest percent of growth already underway is in small cities, such as Gig Harbor.

How might that affect the Key Peninsula? 

Pierce County Councilman Derek Young (D-Gig Harbor) thinks that kind of growth is very unlikely on the KP. The Growth Management Act, adopted by the state Legislature in 1990, was designed to discourage urban sprawl and to encourage growth in identified urban growth areas. 

Young cited a recent study from Earth Economics in consultation with The Puyallup Watershed Initiative entitled, “The Costs of Sprawl: The Potential Impacts of Development in Pierce County, Washington.”

According to that study, Pierce County is one of the most rapidly growing counties in the state and most development is occurring in unincorporated areas. It compared the economic costs of developing in rural and urban areas. The results strongly supported continuing to add population to urban areas and preserving the rural nature of communities like the Key Peninsula, Young said. 

Infrastructure in rural settings costs nearly three times more than it does in urban ones.

Earth Economics estimated the financial cost of losing undeveloped land to housing. Forests, grasslands, wetlands and agricultural lands provide services—they all improve water and air quality, sequester carbon and provide habitat for plants and animals. Some also provide recreational opportunities. Evergreen forests and agricultural lands provide crops and jobs. According to the report, a monetary value can be ascribed to each of these services. 

The study also calculated the cost of providing infrastructure for services in rural Pierce County compared to that in an urban growth area. Infrastructure in rural settings costs nearly three times more than it does in urban ones, it said. 

The study described two scenarios—one of building housing for 100 people (39 households) in an urban growth area and the other in a rural setting. Rural housing is single-family with large lot requirements; new urban housing is more likely to be multifamily on smaller lots. The study assumed homes for 100 people would require 124 acres in a rural location but only 25 acres in an urban one. 

Looking at both the economic losses from building on undeveloped land and the increased cost of infrastructure, the study concluded that development in rural rather than urban communities to house 100 people would lead to about $7 million in losses over a 30-year period.

How much development can happen in rural, unincorporated areas is determined by community plans and zoning regulations. The Key Peninsula Community Plan was completed in 2007 and is not scheduled for revision until 2027. According to the plan, nearly two-thirds of the land use designation is Rural 10. Rural Neighborhood Centers and Rural Activity Centers account for less than 1 percent. Parks, rural farm agricultural and rural sensitive resource lands make up the remainder. 

Of the R10 designated land, the many parcels that are smaller than 10 acres were legally created prior to the current zoning laws. And the R10 designation doesn’t mean that all homes must be on 10-acre lots—there is a maximum density of 0.2 houses per acre. 

Mike Halliday, Public Information Specialist at Pierce County Planning and Public Works, said, “The Pierce County Zoning Code states the Rural 10 zone classification is intended to provide for rural uses at a rural density. In the R10 zone, to get maximum density, 50 percent or more of the property must be designated as open space.” For example, if the property qualifies for the maximum density limit, a 10-acre parcel could be subdivided into two lots.

However, on privately owned land, the landowner can develop as he or she sees fit, as allowed by zoning. According to the county Assessor-Treasurer’s office, more than 91 percent of the 38,149 acres on the Key Peninsula are privately owned. 

Does that mean that parcels currently filled with second-growth trees could potentially become lots for homes?

Young thinks that is unlikely. He said that the growth here is limited compared to Gig Harbor and to other areas in Pierce County. “The Key Peninsula is a long way from urban growth areas,” he said. “I know that as people drive and see new buildings, they have concerns, but the capacity for homes on the peninsula is pretty limited. Wetlands and unstable slopes, water availability and septic issues will all limit growth.” 

He estimates that when Pierce County Planning and Land Services completes its countywide annual buildable lands report the number of buildable sites identified as available for new homes on the KP will be in the hundreds.. 

Read the study at