Basalt Creek

The Cities of Tualatin and Wilsonville are partnering to manage the Basalt Creek Concept Plan.  This collaborative effort will ensure that the property owners, community members, elected officials, and staff from both Cities are involved in creating a vision for the future of this area that enhances the quality of life.

For additional information, please visit the Basalt Creek Concept Plan website at
The Basalt Creek Concept Plan Planning area is generally located between the southern edge of Tualatin and the northern boundary of Wilsonville, where the two cities are less than a mil apart. The Planning Area encompasses approximately 847 acres and includes an area to the west of Coffee Creek Correctional Facility known as the West Railroad Planning Area. 
Basalt Creek study-area-boundary1-150x150
For size comparison, that’s over 700 football fields! Currently, the land is composed of a mix of residences, nurseries, farms, forests, and a creek. In 2004, Metro (Portland’s metropolitan area regional government) added these areas to the urban growth boundary (UGB) for residential and industrial uses.

Watch and listen to a video about Basalt Creek


Employment Development Feasibility Study

The Basalt Creek Concept Plan Existing Conditions report was prepared
in 2014 to look at future development of the 847 acres between the City
of Wilsonville and City of Tualatin as part of the Urban Growth Boundary
(UGB) inclusion process. In that report, potential land uses were identified
for the region based on economic factors, land use compatibility, and
projected growth. The intent of this feasibility study is to take a
further look at approximately 60 acres within the Basalt Creek Concept area
to evaluate the potential to develop these properties to support increased
employment opportunities in the region. This subarea’s potential development
is important because of its central location in the planning area and on the
main intersection of the Basalt Creek Parkway in the future business district.

Feasibility Study - June 2017

What is a Concept Plan and Why do we need one?

In general, a concept plan identifies a vision for the planning area and guides future land use and transportation. Additionally, it outlines an implementation strategy for future provision of urban services (water, sanitary sewer, and storm sewer systems), other public services, and protection of natural and cultural resources.

Although the Basalt Creek Planning Area is part of the UGB, property owners are unable to pursue urban development until a concept plan is completed. Prior to incorporating this land into either City, both Cities wish to address the needs of area residents as well as other community members and set a plan to provide adequate services, coordinate land use and transportation, and preserve natural resources.

How will we get there?

Through your input! This planning effort requires involvement from property owners, community members, elected officials, and other local stakeholders. Interested residents and stakeholders will have the opportunity to voice their input, raise concerns, offer suggestions, and ask questions through a public workshop, open house, community surveys, and public meetings. Based on all of the input gathered, staff from both Cities will devise a plan that seeks to implement the community’s vision as well as regional goals outlined by Metro.

  1. Transportation Refinement Plan
  2. Events and Meetings
  3. Goals and Outcomes

Transportation Refinement Plan

In August 2013, the Cities of Tualatin and Wilsonville, Washington County, and Metro all adopted an Intergovemental Agreement that endorsed the recommendations in the Transportation Refinement Plan. The recommendations in that Plan will form the transportation assumptions for the Basalt Creek Concept Plan. [Download the Recommendations – 2MB]

A combination of new and improved roadways through the Basalt Creek area are envisioned:

  • A new five-lane east-west roadway. The new roadway would be an extension of SW 124th Avenue, aligned south of Tonquin Road and extending to Boones Ferry Road. This has been called the “East-West Concept.”
  • Improvements to existing roadways in the area, such as Tonquin Road, Grahams Ferry Road, Boones Ferry Road, and Day Road.
  • Preserving the ability to construct two new I-5 overcrossings. These overcrossings are recommended as long-term improvements and likely not needed until 2035 or later, depending on growth.

Active transportation improvements include bike lanes and sidewalks consistent with Washington County urban standards, as well as integration of the regional Ice Age Tonquin Trail into the transportation network and consideration of an off-street multi-use path that extends east of I-5. These details will be further refined during concept planning for the area.

Frequently Asked Questions

Concept Planning

Q: Why is future development being planned in Basalt Creek?

A: In 2004, Metro (the regional planning agency for the Portland metropolitan area) added the 847 acres between the cities of Tualatin and Wilsonville, known as the Basalt Creek and West Railroad areas, to the Urban Growth Boundary (UGB). This land was added to help meet the need for industrial land in the region for the next 20 years. It was acknowledged at that time that some residential development would be included in the north part of the area to provide a transition from Tualatin’s residential neighborhoods to industrial development farther south. Once land is brought into the UGB by Metro, local counties and cities are required to plan for urbanization of the land by preparing a Concept Plan, which is a roadmap for development consistent with state, regional and local land use planning laws.

Q: How much development needs to be planned for or accommodated in the Concept Plan?

A: Metro forecasts the number of jobs and housing units that are needed to accommodate expected growth within the UGB for the next 20 years. The most recent forecast for the Basalt Creek area is for about 2,300 jobs and 1,200 housing units. The Concept Plan must provide the framework  to accommodate this amount of jobs and households within the planning area.

Q: What will the Concept Plan accomplish?

A: The Concept Plan will identify land uses including industrial, residential, commercial, parks, trails, and green ways; future city limit lines between Tualatin and Wilsonville; a local transportation network and system of connections for cars, walkers and bicyclists; and how urban services such as water, sanitary sewer, and stormwater will be provided.

Q: What is the schedule for this project?

A: A final version of the Concept Plan is expected to be complete by the fall of 2015. A project schedule can be viewed here.

Q: What is Metro’s role in this project?

A: Metro is the regional planning agency for the Portland metropolitan area. Metro staff serves on the project’s Agency Review Team advising the consultants and staff on various aspects of the Concept Plan. Once the Concept Plan is complete, Metro will review it to ensure that it meets regional requirements for planning within the UGB, specifically Title 11 of the Urban Growth Management Functional Plan.

Q: Will the Basalt Creek area develop as shown on the Concept Plan map?

A: The Concept Plan is a roadmap that guides future development in the Basalt Creek area. Once property receives a city Comprehensive Plan designation, is annexed to a city, and zoning  applied, development must be consistent with the above designations. Future annexation and development applications are reviewed against these designations for consistency. The Concept Plan provides a general framework for development but the timing and location of development and subsequent improvements are determined by landowners through the development review process.

Q: What is the existing zoning in the planning area?

A: Land within the Basalt Creek area is designated Future Development – 20 acre (FD-20) by Washington County. The FD-20 zoning is an interim designation until the Concept Plan is complete and landowners annex their property to either Tualatin or Wilsonville consistent with the Concept Plan jurisdictional boundary. To understand permitted uses in the FD-20 zone, contact the Washington County Department of Land Use and Transportation.

Q: How will the zoning change when the Concept Plan is adopted?

A: Zoning in the Basalt Creek area will not change when the Concept Plan is adopted until landowners request to annex their land to either Tualatin or Wilsonville. At that time, comprehensive plan and zoning is applied, consistent with the Concept Plan..

Annexation and Development

Q: What will happen after the Concept Plan is adopted?

A: Once the Concept Plan is accepted by the Joint Tualatin and Wilsonville City Councils, the Cities will amend their urban planning area agreements with Washington County to add their part of the Basalt Creek area to each City’s urban planning area. Each City Council then individually adopts their portions of the Concept Plan, including it as a sub-element of their Comprehensive Plan.. Annexation is the next step in the planning and development process. This is followed by application for land use approvals, which, pending availability of infrastructure, would allow development and construction to occur. The Cities expect the adoption process to occur in 2016, after which development could be pursued.

Q: When can property be annexed to Tualatin or Wilsonville?

A: Property may be annexed to Tualatin or Wilsonville after the Concept Plan is complete, has been adopted by the individual City Councils, and incorporated in each City’s Comprehensive Plan and in the case of Tualatin, the Development Code. The Concept Plan will include the jurisdictional boundary, which determines the part of the Basalt Creek area that will become part of each City. Tualatin and Wilsonville have specific requirements for property annexation that must be followed for individual properties to be included in each City’s jurisdictional boundary.

Q: When will development start in the Basalt Creek area?

A: Although the Basalt Creek area is part of the UGB, urban development cannot occur until the Concept Plan is completed and each City has adopted the plan and amended their Comprehensive Plan and in the case of Tualatin, the Development Code. Development will be driven by landowners and the private sector. The timing of development will be determined by the market and the availability of infrastructure.

Q: How will this planning process affect property values and taxes in the Basalt Creek area?

A: Future annexation and development of property in the Basalt Creek area will affect assessed property values and associated taxes. City tax rates will be applied when properties are annexed into Tualatin or Wilsonville. Annexed properties receive a more complete set of urban services (sewer, water, and roads) and improved police protection. That difference in service level is the reason for the variation in County versus City tax rates. For detailed questions regarding property values and taxes, please contact the Washington County Assessor’s Office.

Q: How will property rights be respected as part of this process?

A: It is always up to private landowners to decide whether they want to develop their land. The Cities cannot force development, only plan for it if and when it happens. There are many steps that must be taken by landowners before land within the UGB can be annexed, zoned, and developed within the City limits. The Cities of Tualatin and Wilsonville will continue to provide notice to landowners of upcoming presentations and actions throughout the planning process to keep everyone informed. In the event property needs to be taken for public purposes, property rights are constitutionally protected, and governing rules and regulations require the fair market value be determined and paid to the landowner. Exact property value is determined by rigorous state regulations.

Roads and Utilities

Q: How will new infrastructure (roads, sewer, water, stormwater) be paid for and who will pay?

A: New infrastructure is paid for in a variety of ways. In general, the developer is responsible for paying the costs of or actually constructing public infrastructure improvements necessary to serve a property at the time of development. This includes private on-site improvements, and public improvements directly abutting the property, such as sewer, water, stormwater, sidewalks, curbs, gutters, street trees, etc., to City standards. In addition, the developer is responsible for maintenance of certain public improvements abutting the property. In many cases the City assesses system development charges (SDC) on development to pay for new connections or increased size connections on the City’s sewer, water, stormwater drainage, parks and transportation systems. SDCs are intended to pay for the cost of constructing or providing capacity in these city systems sufficient to accommodate new development.

Cities usually have a Capital Improvement Program (CIP) and Plan that provides direction for the planning, design, and construction management of water, sanitary sewer, stormwater, and transportation projects. These projects are funded by the various City operations funds, SDC funds, grants and other funds from federal and state governments. When the Concept Plan is adopted, the SDC schedule and applicable street, sewer, water and stormwater standards and fees are revised to reflect the cost estimate in the Concept Plan. This is intended to help ensure the cost of more urban development is adequately reflected and recovered through the various programs and not left to be borne by area residents alone.

The Concept Plan will also suggest other innovative public financing strategies to finance infrastructure improvements.

Q: Will landowners be required to hook up to utilities? When and what will it cost?

A: The Concept Plan will not require anyone to connect to public water and sewer until the landowner chooses to annex the property to either Tualatin or Wilsonville. It is possible that connection to public utilities would be required if an existing well or septic system on a property fails, cannot be repaired or replaced, the property is located in close proximity to existing public water or sewer, and can practicably connect to the City system. Generally, cities do not provide public services outside their jurisdictional boundaries, meaning that a landowner must agree to complete the annexation process if they are to receive public services. The cost of water or sewer hookup depends on several factors, such as the cost of extending the mains, the number of properties hooking up, and the method of financing.

Q: What agency should a landowner go to if they want to develop or make improvements to their property while the Concept Plan is in process?

A: The Basalt Creek area (except for a small piece in the southern part of West Railroad) is located in unincorporated Washington County. Therefore, landowners need to follow the permitting process in Washington County to develop or make improvements on a property until the Concept Plan is adopted and adopting ordinances are in place.

Q: What is the Transportation Refinement Plan and is it part of the concept planning process?

A: The Transportation Refinement Plan (TRP) was a joint effort between Tualatin and Wilsonville, Washington County, and Metro, to establish transportation connections from Tualatin-Sherwood Road to I-5 in north Wilsonville through the Basalt Creek area. The transportation connections established in the TRP are not part of the Concept Plan but provide the framework for identifying where local roads might be located to feed into the larger regional network. The backbone of the transportation system in the TRP is the 124th to Boones Ferry Road connection, which is intended to be a new, limited access, major arterial through the Basalt Creek area. Other transportation improvements needed to adequately provide improved regional freight mobility also are included in the TRP. More information about the TRP can be found here.

Other Services

Q: Will school district attendance boundaries change when the Concept Plan is adopted?

A: The Basalt Creek area is located in the Sherwood School District attendance boundary. Because school district boundaries do not follow city boundaries, the attendance boundary will not change when the Concept Plan is adopted and students will continue to attend the same schools as they do now.

Q: Will zip code areas change when the Concept Plan is adopted?

A: Zip code areas do not follow city boundaries and will not change as a result of Concept Plan adoption.