Geological Hazards
Commentary
Identify your properties hazards:
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Washington State experiences significant impacts from natural hazards including floods, storms, wild-land fires, earthquakes, and volcanoes. Beyond natural hazards, there are technological hazards, including nuclear power plant incidents, chemical weapon stockpiles, dam failures, and hazardous material spills. All of these require assessment and determination.
Geo-technical report must be provided when the following site conditions exist:
- Proposed structure will be placed in a sensitive or critical area which may include coal mine/erosion hazards, flood hazards, wetlands, streams hazard areas or:
- Landslide hazards
- Steep slope hazards
- Seismic hazard areas
- Erosion hazards
- Provide a geo-technical report prepared by a Washington State Licensed Geo-technical, Geological or Structural Engineer to include original signature and stamp of engineer. All reports must include a statement of risk.
*Please include report at time of submission
WHEN IS WET SEASON LIMITATION REQUIRED?
Land clearing, grading, filling, and foundation work are not permitted between October 1 and April 1 on lots considered as an Erosion, Potential Slide, or Steep Slope Hazard. A waiver to this seasonal development limitation may be granted if compelling justification is demonstrated and supported by a geotechnical evaluation of the site and proposed construction activities. Apply here:
Wet Season Work Waiver - Seasonal Development Limitation
Affected Sites:
- Sites subject to a Potential Slide, Erosion, or Steep Slope Hazard, or any areas with Critical Slopes and the land that extends 10 feet past the top and toe of the slope.
- Any site that is considered by the Building Official or City Engineer to be subject to the seasonal development limitation.
