Every figure on LotTruth comes from a public record, and every report links the record it came from with the date it was last updated. This page lists the records and how each answer is worked out.
The records
Pierce County Assessor-Treasurer: parcels, values, buildings and sales.
Pierce County maps: zoning, the urban growth area, sewer service areas and mains, streams, wetlands, and landslide, erosion and flood hazard areas.
Tacoma-Pierce County Health Department: septic (on-site sewage) records.
Pierce County and the City of Tacoma: building permits.
U.S. Department of Transportation National Address Database: every Washington address, for search.
The county's records are collected weekly; a lot's report shows the date of each.
Latest collection: sales November 7, 2026 · sewer October 2, 2026 · sewer_mains_tacoma November 7, 2026 · stream November 8, 2026 · wetland September 28, 2026 · zoning September 29, 2026 · zoning_pierce November 8, 2026 · zoning_tacoma September 28, 2026
How the answers are worked out
ADUs: a lot zoned for houses inside a city or the county's urban growth area falls under Washington's HB 1337, which requires two ADUs to be allowed. Septic and hazard notes come from the lot's own records.
Sewer or septic: septic records on file mean a system; a nearby sewer main (county, town or private) and a sewer service area point to sewer. Dry lines, laid for homes still on septic, do not count. City sewers are not on the county's maps, so a city lot is never called septic from distance alone.
Hazard areas: the share of the lot's outline inside each mapped area.
Nearby lots: the 25 nearest lots within a quarter mile; sales are single-parcel warranty-deed sales over $1,000 in the last three years.
These are the public records, not a survey, an inspection or a determination by any office. Check with the office that keeps a record before relying on it.