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24.51.020 Definitions

(Amended by Ordinance No. 180917, effective May 26, 2007.)  The definitions contained in this Section relate to Wildfire Hazard zones and considerations outlined in this Chapter.

A.   Chief means the Chief of Portland Fire & Rescue or the Chief’s duly authorized representative.

B.  Department of Forestry (DOF) means the State of Oregon Department of Forestry.

C.  Wildfire Hazard Zone means those areas of the City as determined by the Chief that rate a minimum score of 5 or higher using the following criteria developed by DOF:

1.  Topography hazard factor value

2.  Natural vegetative fuel hazard factor value

3.  Natural vegetative fuel distribution hazard factor value

D.  Wildfire Hazard Zone Map means the WHZM attached to Ordinance No. 177433 and as it may be amended from time to time based on the criteria herein.

E.  Hazard Factor. Hazard Factors are topography, certain natural vegetative fuels and natural, vegetative fuel distribution.  Any of these factors, or a combination thereof, may cause an area of the City to be included within a Wildfire Hazard Zone.

F.  Topography Hazard Factor Value means the hazard value as determined by DOF associated with site slope which effects the fire spread velocity.

G.  Natural Vegetative Hazard Factor Value means the numerical value assigned by DOF, extrapolated from the “Aids to Determining Fuel Models for Estimating Fire Behavior” published by the Forest Service, USDA Intermountain Forest and Range Experiment Station in 1982 as General Technical Report INT-122, for various common vegetation.

H.  Natural Vegetative Fuel Distribution Hazard Factor Value means the numerical value assigned by DOF for the percentage of site that is covered by vegetation described in 24.51.020 G.