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Channel Debris Clearing <br />Channel- debris dearing removes debris from the channel and flood proneareas that could <br />dislodge and plug culverts or damage downstream property. High priority areas for treatment <br />would include areas in close proximity to houses and directly upstream from culverts. Debris may <br />include burned wood from trees and debris from burned structures. Generally, this treatment <br />would be done manually with a focus on small debris considered likely to be transported <br />downstream. <br />Sediment Basins and Debris Racks <br />Sediment basins and debris racks will be pursued at locations that lend themselves to such <br />measures. This would be at locations where there is an opportunity to trap and settle out <br />suspended sediments before they reach a main channel or where large amounts of woody debris <br />are likely to be generated (e.g., Fall, Hill or Watha watersheds) and may adversely impact <br />downstream structures or infrastructure. Periodic cleaning of such facilities would be necessary <br />to regain retention capacities. <br />Floodwater Detention or Diversion Facilities <br />Although more detailed hydrologic analyses are currently being conducted by the NRCS, field <br />observation suggests that the Belivue community may be at significantly increased risk for <br />flooding from the upstream burned watersheds. Most of the community and CR 23 are located in <br />the historic drainage way for Mill Canyon. Once more detailed hydrographs are developed; it <br />may be appropriate to determine if there is any flood storage or channel diversion alternatives <br />that would help mitigate for this increased flood risk. <br />ROAD TREATMENTS <br />Storm Inspection and Response <br />Storm inspection and response keeps culvert and drainage structures functional by cleaning <br />sediment and debris from the inlet between storm events on public roads where access is <br />required. Typically, crews drive the roads during or immediately after storms, checking sediment <br />and debris accumulations and performing thorough, rapid inspection of road drainage features, <br />culverts, and other structures. The crew is responsible for maintaining culvert function by opening <br />culvert inlets and removing debris. Within the regular duties of County road maintenance crews, <br />routine road, culvert and infrastructure inspections are performed. <br />Additional inspections within the burn area will be added to regularly scheduled inspections. <br />Crews will inspect culverts and ditches for debris prior to storm event runoff, and remove any <br />accumulated debris or sedimentation from those locations. Crews will also monitor high risk areas <br />during storm events to immediately identify areas at risk of flooding or debris sedimentation. <br />Following a storm event, crews will identify areas that have been impacted and respond by <br />initiating a cleanup effort to remove accumulated sediment and debris from roadways, or repair <br />damaged infrastructure <br />Increase culvert diameters at drainage crossings, add drainage, and armor drainage <br />outlets <br />Minor Structures (having a span of from 4' to 20') and culverts that are used for roadway drainage <br />(ditch relief culverts) and channel crossings contribute to the watershed emergency when they <br />are damaged in a fire or when their hydraulic capacity is marginal. Post -fire sediment and debris <br />flow in channels may plug structures or culverts and increase the diversion - potential risk. <br />High Park Fire Emergency Stabilization Plan Page 21 <br />