Planned Transportation Improvements, Snohomish County, Washington

The Snohomish County Arterial Network (SnoCAN) Plan was founded to coordinate local jurisdictions in their search for federal and state funds for transportation improvement programs. Participating members in the Snohomish County Infrastructure Coordination Committee determined that there needed to be a way to share transportation improvement project information among jurisdictions' transportation improvement programs and comprehensive plans (transportation elements) to coordinate grant application efforts. The proposed solution would integrate information in both a database and a map of proposed project locations. Taking the lead in this effort, Snohomish County Public Works in conjunction with Snohomish County Tomorrow outlined a project to accomplish interagency coordination. The project was further designed and later implemented using transportation planning and technical GIS consultants.

The following needs were identified: transportation links of countywide significance, development of a common language or nomenclature for identifying project types and project attributes, and creation of a data management system to compile the information including a GIS map interface for viewing the location of the projects.

The resulting data management system implemented Oracle for data management and ArcView as the mapping front end. The projects are linked to the arterial centerlines in ArcView using linear referencing, with the Puget Sound Regional Council of Government's framework transportation segments as the background linear referencing system.

The SnoCAN model is a demonstration of how GIS technology can be used to unify local jurisdictions to improve regional traffic mobility.