Property Research and Historic Zoning Codes and Maps

Property Resources

Online Map Portal – Search historic information submitted with applications to the City’s Development Services Group for specific parcels, such as building permits, sewer as-builts, and geotechnical reports. Check out our GIS Records Search Guide for help finding files online. Other GIS information available includes recent and historic aerial photos, Capital Improvement Projects (such as roads), trails, crime and fire information, and much more!

MyBuildingPermit.com – Check the permit status of building and land use permits (or apply for a new one). 

King County Recorders Office – Search for recorded plats, surveys, deeds, and other documents.

King County Historic Zoning information – Prior to becoming a City, property was under the zoning authority of the county.

King County Department of Assessments – View values and sales history for all property in King County.

Oblique Aerial Photos – In addition to the aerial photos from the city, the Washington State Department of Ecology (D.O.E) has high resolution oblique aerial photos of the properties at and near the Mercer Island shoreline, which can be accessed from the D.O.E. Coastal Atlas.

Washington State Archives – Certain documents that the City or County have chosen not to retain may be retained by the State. The State Archives maintains a list of documents retained, including tax assessment rolls which includes the record of tax assessments, photographs of the buildings, description of construction, date of construction, small sketch of the exterior plan of buildings (including dimensions), segregation dates, numbers for land parcels, some ownership information, and some excise numbers. Occasionally, (for post-1937 construction) building permit numbers are included. The Puget Sound Regional Branch is in Bellevue, and can be reached at 425-564-3940.

Use of Historic Zoning Codes and Maps Below

Below is a list of zoning codes available, which are adopted by City Council via ordinances. The zoning codes are helpful in determining the applicable zoning regulations in place for a certain time period. 

‘City of Mercer Island’ and ‘Town of Mercer Island’

When examining previous zoning regulations, it is important to note that the City of Mercer Island incorporated on July 5, 1960, while the Town of Mercer Island (consisting mainly of the current Town Center) on August 9, 1960. The Town of Mercer Island merged into the City of Mercer Island on May 19, 1970. The fact is important, as there was a different jurisdiction governing the Town Center area prior to the merging of the two jurisdictions.  Many of the records for the Town of Mercer Island were not retained. Below is the most relevant information related to zoning that is available.

Links to Historic Zoning Codes and Maps

The below table includes hyperlinks to snapshots of zoning codes and significant ordinances that were effective at different points in time. *Note that the documents are scanned and formatted (OCR) to allow text searching in Adobe Acrobat Reader, PDF X-Change Viewer, or similar .pdf compatible software.