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20 ac (8 ha). Bales usually last leas than 3 months, flow
<br />should not be greater than 11 cfs (0.3 ma s 1), and bales
<br />should be removed when sediment depth upstream is
<br />one-half of bate height. More damage can result from
<br />failed barriers than if no barrier were installed
<br />(Goldman and others 1986).
<br />Log Check Dams--Logs 12 to 18 in (300 to 450 mm)
<br />diameter were used to build 14 log check dame that
<br />retained from 1.5 to 93 yda (mean 29 yd3) (1.1 to 71 ma,
<br />mean 22 ma) of sediment after the 1987 South Fork
<br />Trinity River fires on the Shasta-Trinity National
<br />Forest, California (Miles and others 1989). While log
<br />check dams have a high effectiveness rating and 16 to
<br />30 year life expectancy (Miles and others 1989), they
<br />are costly to install (table 8).
<br />Rock Dams and Rock Cage Dams (Gabions)-Prop-
<br />erly designed and installed rock check dame and rock
<br />cage (gabion) dame are capable of halting gully devel-
<br />opment on fire-disturbed watersheds, and reducing
<br />sediment yields by 60 percent or more (Heeds 1970,
<br />1976). Although these structures are relatively ex-
<br />pensive, they can be used in cot}junction with vegeta-
<br />tion treatments to reduce erosion by 80 percent and
<br />suspended sediment concentrations by 96 percent
<br />(Heeds 1981). While vegetation treatments such ae
<br />grassed waterways augment rock check dams and are
<br />less expensive, their maintenance coats are conaider-
<br />ablygreater. Check dame constructed in Taiwan water-
<br />eheda with annual sediment yields of 10 to 30 yda ac t
<br />(19 to 57 ms ha 1) filled within 2 to 3 years. Sediment
<br />yield rates decreased upstream of the check dams,
<br />but were offset by increased scouring downstream
<br />(Chian-Ming 1985).
<br />Other Channel Treatments-No published infor-
<br />mation was found on the effectiveness of straw
<br />wattle dams, log grade stabilizers, rock grade stabi-
<br />lizers, in-channel debris basins, in-channel debris
<br />clearing, stream bank armoring or other BAER chan-
<br />nel treatments.
<br />Road Treatments-BAER road treatments con-
<br />sist of a variety of practices aimed at increasing the
<br />water and sediment processing capabilities of roads
<br />and road structures, such as culverts and bridges, in
<br />order to prevent large cut-and-fill failures and the
<br />movementofaedimentdownatream. Thefunctionality
<br />of the road drainage system is not affected by fire, but
<br />the burnedover watershed can affect the functional-
<br />ityofthat eyetem.Road treatments include outsloping,
<br />gravel on the *~inn;ng surface, rocks in ditch, culvert
<br />removal, culvertupgrading, overflows, armored stream
<br />crossings, rolling dips, and water bare. The treat-
<br />mentsare not meant to retain water and sediment, but
<br />rather to manage water's erosive force. Trash racks
<br />and storm patrols are aimed at preventing culvert
<br />blockages due to organic debris, which could result in
<br />road Failure that would increase downstream flood or
<br />sediment damage.
<br />Furnies and others (1998) developed an excellent
<br />analysis of factors contributing to the failure of
<br />culverted stream crossings. Stream croasinga are very
<br />important, as 80 to 90 percent of fluvial hillelope
<br />erosion in wildlands can be traced to road fill failures
<br />and diversions of road-stream croasinga (Best and
<br />others 1995). Since it is impossible to design and build
<br />all stream crossings to withstand extreme stormflows,
<br />they recommended increasing crossing capacity and
<br />designing to minimize the consequences of culvert
<br />exceedence as the best approaches for forest mad
<br />stream crossings.
<br />Comprehensive discussions of road-related treat-
<br />ments and their effectiveness can be found in Packer
<br />and Christensen (1977), Goldman and others (1986)
<br />and Bunrougha and King (1989). Recently the USDA
<br />Forest Service, San Dimas Technology and Develop-
<br />ment Program has developed a Water/Road Interac-
<br />tion Technologies Series (Copstead 1997), which cov-
<br />ers design standards, improvement techniques, and
<br />evaluates some surface drainage treatments for re-
<br />ducing sedimentation.
<br />Methods
<br />This study was restricted to USDA Forest Service
<br />BAER projects in the Western continental United
<br />States (Regions 1 through 6). We began by requesting
<br />Burned Area Report (FS-2500-8) forms and monitor-
<br />ingreports from the Regional headquarters and For-
<br />est Supervisors' offices. Our initial efforts revealed
<br />that information collected on the Burned Area Report
<br />forma and in the relatively few existing poatfire
<br />monitoring reports was not sufficient to asse~streat-
<br />ment effectiveness, nor did it capture the information
<br />knowledge ofBAER specialists. Therefore, we designed
<br />interview questions to enable us to rank treatment
<br />effectiveness, determine aspects of the treatments
<br />that lead to success or failure, and allow for comments
<br />on various BAER related topics.
<br />Burned Area Report Data
<br />The Forest Service Burned Area Report form con-
<br />tainathe fire name, watershed location, size, supprea-
<br />aion coat, vegetation, soils, geology, and lengths of
<br />stream channels, roads, and trails affected by the fire.
<br />The watershed description includes areas in low,
<br />moderate, and high aeverityburn categories and areas
<br />that have water repellent soils. Erosion hazard rating
<br />and estimates of erosion potential and sediment
<br />delivery potential are included, based on specified
<br />design storms. The probability of success for hillelope,
<br />USDA Forest Service Gen. Tech. Rep. RMRS-GTR-s3.2000 21
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