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Environmental/Implementatron Factors Rolling dips are easily constructed with read grader or dozer. Rolling dips or waterbara need to be deep enough to contain the expected flow and location carefully as- sessed to prevent damages to other portions of the road. Waterbara can be made out of rocks or logs. Armoring of fillslope at the outlet is often needed to prevent gullying. Culvert Upgrade Purpose: Culvert improvements increase the flow ca- pacity which will prevent damage to reads. Relative Effectiveness Excellent-0% Good-80% Fair- 0% Poor-20% (Replies = 5) When sized properly and installed correctly, the re- sults were rated °good." The °poor" rating was from culverts that were still not large enough and failed. Enviromnental/Implementatron Factors Upgraded culverts need to be sized properly based on expected increased flows. They should be installed at the proper elope with appropriate approaches and exits. To be effective, upgraded culverts need to be installed before the first damaging rainfall, Flexible down spouts and culvert extensions often are needed to keep exiting water from highly erodible elopes. Storm Patrol Purpose: Patrol during storm events provides immedi- ate assessment of flood risk, clear blocked culvert entrances, anddrainageditchesandcloaeaccese(gates) to areas that are at risk. Relative Effectiveness No interviewee rated this treatment. Several interviewees indicated that storm patrol was a coat effective alternative to installing trash racks, or removing culverts. Environmental/Implementatron Factors. This treat- ment canincludeearly warning systems such as radio- activated rain gauge or stream gauge alarms when flows are increasing. Storm patrols remove floating woody debris near culvert inlets and clean inlets after each storm event. Storm patrols can be activated during forecast events of weather which may trigger larger than normal water, sediment or woody debris flows. Culvert Inlet%Outlet Armorine/Risera Purpose. These treatments reduce scouring around the culvert entrance and est. They allow heavy par- ticles to settle out of sediment laden water and reduce the chance of debris plugging the culvert. Relative Effectrveness Not enough interviewees rated this treatment to make any statements about its effectiveness. Envlranmental/Implementatron Factors Sometimes culvert risers can clog and may be difficult to clean. Trash Racks Purpose. Trash racks are installed to prevent debris from clogging culverts or down stream structures. Relative Effectiveness Not enough interviewees rated this treatment. Comments included that in one watershed the third winter after the fire, a large storm detached wnaider- able debris which blocked trash rack, causing com- plete culvert failure. Environmental/ImplementadonFactors These struc- tures are generally built out of logs, but occasionally they are from milled lumber or metal. Sizes vary from small culverts to 30 ft (9 m) diameter. Several cage designs have been used with moat of them allowing debris to ride up and to the aide ofthe cage. Some cages have been set in concrete. Trash racks generally per- form better in smaller drainages. They need to be cleared after each storm to be effective. Culvert Removal Purpose. This procedure removes undersized culverts which would probably fail due to increased flows, in a controlled fashion. Relative Effectiveness No interviewee rated this treatment. Environmental/Implementation Factors: Removal needs to be completed before the first damaging storms. It is often done in conjunction with mad obliteration. Ditch Improvements: Cleaning/Armoring Purpose. Cleaning and armoring provides adequate water flow capacity and prevents downcutting of ditches. Relative Effectiveness. No interviewee rated this treatment. Environmental/ImplementattonFactors Whenmain- tenance does not occur, high water levels can overtop roadways leading to gully development in the road bed. Armoring Ford Crossing Purpose. Armored crossings provide low-coat access across stream channels that are generally capable of handling large flows. 84 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-63.2000