Description: The back story on this dataset is that EWEB desired a prioritization analysis for private taxlots in (and near) the Holiday Farm Fire burn area in order to help guide their efforts to do on the ground assessments for erosion control/stabilization work (and other assessments) related to minimizing impact to water quality from the fire.
The details of the model that produced this layer are given below. Basically, the model selects eligible (mostly private) properties that are within the Holiday Farm Fire burn area plus a one mile buffer and also in the McKenzie River watershed above the EWEB drinking water intake. These properties are evealuated against the following layers: the USGS post-fire debris flow likelihood/volume combined risk dataset https://landslides.usgs.gov/hazards/postfire_debrisflow/detail.php?objectid=339), distance from the McKenzie River and tributary streams, lot size, burn severity, and presence of structures and burned structures in a weighted model to derive the priority value (1 – 17, with 1 being highest priority to assess).
• Industrial forest lands (F1 zoning) and public lands, with the exception of Lane County Parks, and were excluded.
• Priority was calculated using a raster analysis.
• Priority is based on a weighted average of factors by taxlot. The highest weighted average is given the highest priority (lowest priority number).
• Four factors were calculated as index grids with values that ranged from 1 to 3, with 3 being the greatest impact.
o Impact of USGS post-fire debris flow likelihood/volume combined risk (substituting burn severity where debris flow risk values were not available)
(Weight = 2)
1: Low
2: Moderate
3: High
o Impact of distance from NHD tributary stream or larger water body (i.e. the river)
(Weight = 3)
1: Low/Farther (> 120’)
2: Moderate/Near (60’-120’)
3: High/Very Near (0’-60’)
o Impact of lot size
(Weight = 1)
1: Low/Farther (> 120’)
2: Moderate/Near (60’-120’)
3: High/Very Near (0’-60’)
o Impact of presence of structures or burned structures from OSFM 1st pass assessment
(Weight = 1)
1: Low/No Structure Present
2: Moderate/Structure Present
3: High/Burned Structure Observed