System Development Charges (SDC)

Transportation System Development Charges (TSDC)

Updated December 10, 2020

County Code, Section 11.03.030(J), states, "The Construction Cost Index shall be used by County staff to adjust the TSDC Rate Schedule each fiscal year, unless it is otherwise adjusted by the Board based on adoption of an updated Methodology or TSDC Capital Project List.

All Clackamas County TSDCs increased by 0.9498% effective January 1, 2021. The rates apply to building permits submitted on, or after, January 1, 2021. To view the current fees, please click here.

TSDCs are one-time fees assessed on new or expanded developments in unincorporated Clackamas County based on the number of vehicle trips a particular land use generates. The fees are set to cover the cost of transportation facilities needed to serve the new or expanded development and the people who will occupy or use the development.

TSDCs in unincorporated Clackamas County


A TSDC can be included in the final calculation of building permit fees for residential and commercial projects, if applicable.

  • A TSDC is included in the final calculation of building permit fees for commercial projects.
  • Any new single-family residence, accessory dwelling unit or manufactured home is assessed a TSDC.
  • Replacement dwellings are not charged a TSDC. County staff may require a replacement dwelling agreement to confirm the prior residence.
  • Residential accessory structures (garages, shops, etc.) are not charged a TSDC.
  • A guest home, as defined by ordinance, is not assessed a TSDC.

For more information, contact Wendi Coryell at, 503-742-4657 or in Transportation Engineering on the third floor of the Development Services Building, 150 Beavercreek Road, Oregon City, OR 97045.

Residential permits

TSDCs for new or expanded residential dwellings are as follows:

Type of development TSDC per unit
Apartment $3,207/dwelling unit
Mobile Home in Park $2,406/space
Residential Condo/Townhouse $2,802/dwelling unit
Small Accessory Dwelling Unit
(200–449 square feet)
$1,414/ dwelling unit
Large Accessory Dwelling Unit
(450–900 square feet)
$2,829/ dwelling unit
Small Detached Single-Family Home
(dwelling units 1,699 square feet or less)
$4,053/dwelling unit
Medium Detached Single-Family Home
(dwelling units 1,700–3,000 square feet)
$4,622/dwelling unit
Large Detached Single-Family Home
(dwelling units more than 3,000 square feet)
$4,886/ dwelling unit

Commercial permits/statement of use

All commercial permits (including new uses, change of occupancy and tenant improvements) must include a completed Statement of Use form to be reviewed by the Engineering Division before the permit is issued so that any applicable TSDC rate can be determined. TSDC rates vary depending on the use of the structure. This form is needed to clarify the type of development and past use of the space.

The Statement of Use form must be completed in full and returned to the Engineering Division prior to permit issuance:

  • by email to Wendi Coryell at
  • in person or by mail to the third floor permits lobby in the Development Services Building, 150 Beavercreek Road, Oregon City, OR 97045.

Parks System Development Charges (PSDC)

Parks System Development Charges are one-time fees charged to new development to help pay a portion of the costs to meet parks and recreation needs created by growth. PSDC fees are set by the North Clackamas Parks & Recreation District (NCPRD) based on the specific impact a development inside the NCPRD boundaries is expected to have on the District's population and employment.