Too many landslide zones for a ban in Snohomish County

EVERETT — There are so many landslide hazards in the Washington county where a mudslide buried dozens of homes that a moratorium on some new-home construction would make most of the unincorporated areas of the county off-limits to builders, Snohomish County officials said.

The County Council backed away from a proposal Monday for a moratorium on new homes within a half-mile of known landslide areas. Council members said it would take at least two more weeks to consider emergency land use changes in response to the March 22 Oso mudslide that killed 41 people and left two missing.

After seeing a map with the proposed half-mile moratorium, Council Chairman Dave Somers said the measure would have been overly broad for landslide hazards while notoriously flood-prone river valleys would have been unaffected.

Somers had asked the council to consider a temporary home-building ban, The Daily Herald reported.

The council staff has been working on increasing building setbacks and requiring engineering studies in potential landslide areas. Existing regulations generally require buildings be set back at least 50 feet or half the height of an identified landslide hazard slope, whichever is greater.

The hillside that collapsed above Oso was roughly 600 feet high and sent debris at least 3,700 feet from base of the hill at the edge of the North Fork Stillaguamish River.