Of the 4,497 lots in Sumner, 387 touch a mapped landslide hazard area, 226 an erosion hazard area, 927 a flood area and 83 an inventoried wetland, on Pierce County's maps.
A mapped hazard area means the county may ask for a study or a buffer before building; it does not mean the land is unsafe.
The share of each lot inside each area is on its report.
Questions
How much of Sumner is in a landslide area?
387 of Sumner's 4,497 lots touch a mapped landslide hazard area.
What does a hazard area mean for building?
The county can ask for a geotechnical study, a flood elevation or a wetland buffer before it permits building. Search an address to see how much of that lot is affected.
From the Pierce County Assessor-Treasurer, the county's zoning, sewer, hazard and growth-area maps, and the Tacoma-Pierce County Health Department. Records as of October 2, 2026.