Seaside review finds limited buildable land, highlights infrastructure barriers to housing

Consultants and county staff told Seaside city leaders at a work session that the city’s apparent land capacity for new housing shrinks sharply once regulatory and physical constraints are removed, and that infrastructure limits and a high share of second homes complicate meeting the community’s affordable‑housing needs.

Clatsop County housing manager Alyssa Gertler said the project — funded by a grant from the Oregon Department of Land Conservation and Development and prepared for each city in the county — updates the 2019 study and compiles a buildable land inventory, infrastructure needs and a housing supply analysis. “Seaside, in particular, has really been quite proactive about housing and taking really good steps to help you think about how this might inform what you do next,” Gertler said.

Steve Foster of 3j Consulting, who led the inventory work, said the team began with all residentially zoned land and then removed parcels restricted by stream corridors, steep slopes, wetlands, public rights of way, parks, small already‑developed lots and properties not serviceable by infrastructure. “When we take all those things out, we’re left with our buildable land,” Foster said. After removing constraints, the draft inventory identifies about 83.5 buildable acres in Seaside; consultants noted that a large privately owned area often shown as vacant (Thousand Trails) likely inflates the preliminary total and that removing it would drop the figure substantially.

The inventory also shows a fragmented supply: 232 buildable lots, 99 of which are smaller than one acre, and 20 parcels that are five acres or larger but contain only about 29 buildable acres once constraints are removed. Foster warned that parcels that appear large on a map may be unbuildable in practice because of slope, wetlands, or floodplain.

The consultants summarized housing‑market data showing Seaside’s household composition and affordability pressures. The city’s occupied housing is approximately 54% renter and 46% owner; about 51% of renters and about 38% of owners are cost‑burdened (paying 30% or more of income for housing). Nearly 29% of housing units in Seaside are vacant (roughly 1,500 units); consultants reported approximately 90% of those vacancies are second homes or short‑term rentals, and only about 4.6% of vacant units appear to be available for sale or rent.

On population and demand, Foster noted Portland State University’s forecast that Seaside could add roughly 2,000 residents over the next 50 years, a projection some local officials said feels low following COVID‑era moves. Gertler and Foster also explained the state’s new housing capacity analysis, which assigns Seaside a one‑year target of 42 housing units and a 20‑year allocation of a little more than 1,800 units; because Seaside’s population is under 10,000, those numbers are not binding targets but indicate a sizeable deficit in lower‑income units. Consultants stressed that most of the state‑allocated need is concentrated at the 0–30% area‑median‑income level, which will require subsidy and other interventions to address.

Infrastructure constraints were a recurring theme. Foster and county staff said systemwide needs identified in water, sewer and transportation plans (for example, wastewater treatment, water filtration and pump stations) do not always specify what improvements are required to serve particular opportunity sites. The city has an RFP pending to update the wastewater plan, and staff expect a water master plan update within the next year; consultants said the inventory and final report will be constructed so updated system plans can be inserted to refine site feasibility.

Council members and attendees asked for parcel‑level data and clarifications. The consultants agreed to deliver zoomable maps that show tax‑lot lines and to accept corrections from city staff and councilors. Jeff, Seaside’s community development director, asked councilors to review the ward‑level maps once available and send parcel‑specific questions to city staff. No formal action or vote was taken at the work session.

Next steps spelled out by staff and consultants include refining the buildable land inventory with council feedback, providing parcel‑level maps and a final executive summary, and updating infrastructure plans so the city can better assess which sites could realistically be served and developed.