Planning commission backs three-tier approach for CFEC parking standards; staff to refine solar/canopy options

Wilsonville planning staff asked the commission May 14 for feedback on draft development-code revisions to bring city parking-lot standards into alignment with Oregon’s CFEC rules. Staff and commissioners agreed on a three-tiered approach (less than 40 spaces, 40–200 spaces, and more than 200 spaces) and asked staff to refine language governing tree canopy, interior planting and the option to use on-site solar as partial alternative compliance.

Why it matters: The CFEC program sets climate-focused standards for new parking areas in Oregon. Key differences between existing Wilsonville standards and the CFEC rules include the CFEC threshold for enhanced requirements (40 parking spaces) versus Wilsonville’s current enhanced-threshold of more than 200 spaces, and CFEC’s baseline canopy requirements with limited allowance to substitute solar generation for part of required canopy.

Staff presentation and proposed approach

Planning manager Dan Polley reviewed the city’s existing parking-lot requirements (screening, landscape area and tree-to-space ratios; enhanced standards for large lots) and identified the primary compliance gap: CFEC’s mid-tier threshold at 40 spaces. In response to commissioner feedback the project team proposed a three-tiered compliance structure:

- Lots under 40 spaces: continue to follow current city standards. - Lots with 40–200 spaces: apply a tailored set of enhanced standards that meet CFEC’s intent but account for land-use trade-offs cited by commissioners. - Lots over 200 spaces: continue to follow the city’s existing enhanced standards (already consistent with CFEC high-tier requirements).

Tree canopy, solar and alternative compliance

Staff explained the CFEC baseline canopy target is 30% tree canopy for parking areas; the city’s existing enhanced standards currently require about 40% canopy for larger lots. CFEC allows limited alternative compliance where a portion of the canopy requirement can be met by on-site solar generation under defined calculations; staff’s draft implements the CFEC-compliant option where 0.5 kilowatt of on-site generation can substitute for one parking-space-equivalent of the canopy calculation (consistent with CFEC language staff cited).

Commissioner input and clarifications requested

Commissioners broadly supported the three-tier approach and discussed several technical points:

- Location of canopy: A commissioner asked whether trees planted along the right-of-way or edge of a site count toward the parking-lot canopy requirement; staff said canopy that overhangs the parking area counts toward the parking-lot canopy but street trees wholly outside the lot do not except where the canopy extends over spaces.

- Interior planting percentage: Commissioners questioned a draft requirement that at least 25% of required trees be planted in the interior of parking areas (rather than only at perimeters); staff said the 25% interior requirement is existing code language or CFEC-derived and offered to follow up with citations.

- Solar versus rooftop versus covered parking: Commissioners noted trade-offs: on-site solar over parking stalls can provide shade similar to trees and is a practical location for solar, but rooftop solar may produce equivalent emissions reductions. Staff noted CFEC allows specific solar substitutions and the draft implements those options. Commissioners encouraged staff to ensure code language does not unintentionally disincentivize on-site solar or make compliance disproportionately complex.

- Street-like features and acreage thresholds: Commissioners asked about references to acreage (a three-acre threshold in existing code) versus number-of-space thresholds. Staff explained the code contains legacy language that uses acreage in one standard and will reconcile the differing thresholds as the code is finalized.

- Performance and species selection: Commissioners advised against listing specific tree species in the development code; staff agreed to keep species selection at the design/landscape standard level and maintain performance-based canopy requirements.

Next steps and public hearing

Staff said they will refine the draft code to address commissioner feedback, check citations for CFEC-derived provisions (for example the 25% interior-tree requirement and the 0.5-kW solar substitution rule), and present the edited amendments at a public hearing next month.

Provenance: The CFEC parking-design presentation opened with Planning Manager Dan Polley’s overview of thresholds and canopy/solar options and concluded with commissioner discussion and staff commitments to refine draft code language prior to a public hearing.

Ending: Commissioners generally supported the three-tier approach and asked staff to refine the code language so the solar/canopy alternative is clear, implementable and does not discourage solar installations or reduce on-site canopy by default.