City of Spokane

Spokane Municipal Code

***Note: Many local criminal codes can now be located under Chapter 10.60 SMC while others are now cited under the Revised Code of Washington (RCW), which was incorporated into the municipal code in 2022. (See SMC 10.58.010). Code Enforcement, including Noise Control and Animal Regulations are located in Chapters 10.62 through 10.74.

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Title 17E
Chapter 17E.040
Section 17E.040.040
 

Title 17E Environmental Standards

Chapter 17E.040 Spokane Geologically Hazardous Areas

Section 17E.040.040 Identification, Designation and Mapping of Critical Areas

Data sources are available from the City of Spokane that are used in the mapping of the characteristics for geologically hazardous areas. The existing map sources provide a general level of information and are not intended to pinpoint geologic hazards on individual sites or properties. In addition, there may be areas not designated on the City of Spokane maps that exhibit the characteristics of geologically hazardous areas. It is the intent of this chapter to require all areas which meet the classification characteristics of geologically hazardous areas to meet the requirements of this section. The City will maintain a collection of potential geologically hazardous area inventory maps for purposes of providing information on the general location of geologically hazardous areas. Use of the maps shall be for informational purposes only. Lands that meet the classification characteristics for erosion and landslide hazard areas are mapped. In the event that any of the geologically hazardous designations shown on the City maps conflict with the criteria set forth in this chapter, the criteria shall prevail. The geologically hazardous areas maps shall be updated as more accurate information becomes available to aid the public and project reviewers. Classification characteristics are identified as follows:

  1. Soil characteristics are identified as those areas containing soils which according to the Natural Resource Conservation Service (NRCS) Classification System may experience severe to very severe erosion based on a formula, which is based on several factors including rainfall, slope, soil erodibility and other factors. Landslide hazard areas are based on a combination of geologic, topographic (slope) and hydraulic factors and have a high susceptibility to landslides.
  1. Geologic characteristics are areas identified and described by the Washington State department of natural resources and include:
    1. alluvium,
    1. landslide deposits,
    1. Latah formation.
  1. Topographic characteristics include areas within the City of Spokane with severe site topography or slopes of thirty percent or greater and have a severe potential for erosion and/or landslide hazards.
  1. Other characteristics such as hydraulic features including surface and groundwater conditions and the hydraulic changes resulting from a development proposal. Uncompacted fill-areas or steep-cuts as a result of site grading, construction activities or resource extraction.

Date Passed: Monday, December 3, 2007

Effective Date: Sunday, January 6, 2008

ORD C34149 Section 8