Carbonado, WA: ADUs, septic or sewer, land prices and hazard areas

Carbonado, WA ADU rules: can I build an ADU?

321 of the 570 lots in Carbonado (56%) are zoned for houses inside an urban growth area. On those lots, Washington's HB 1337 requires the city or county to allow at least two accessory dwelling units (ADUs). Another 155 lots are outside the urban growth area, where Pierce County's own ADU rules decide.

Carbonado, WA septic or sewer: septic records and sewer mains

81 of the 570 lots in Carbonado (14%) have septic records on file with the Tacoma-Pierce County Health Department. 0 lots are inside a Pierce County sewer service area, and 0 are within 300 feet of a sewer main on the county's sewer map.

Carbonado, WA land prices: vacant land and home sales

Vacant land in Carbonado sold for a median of $68,218 per acre across 8 sales since November 1, 2023. Homes sold for a median of $547,000 across 38 sales. 6 new homes were permitted on its unincorporated lots since November 1, 2021. The city issues its own permits, which are not in our data yet.

Carbonado, WA flood zones, landslide and wetland areas

Of the 570 lots in Carbonado, 219 touch a mapped landslide hazard area, 49 an erosion hazard area, 45 a flood area and 4 an inventoried wetland, on Pierce County's maps.

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 November 8, 2026.

How these numbers are worked out · Guides

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