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Discussion The BAER evaluation process provides a means to assess the postfire emergency and identify appropri- ate treatments. Although our original intent was to evaluate treatment effectiveness, our efforts to com- pile information on individual fires produced a large database of information on the BAER assessment process itself. Treatment effectiveness depends in part upon appropriate treatment selection, and that depends on accurately identifying the emergency con- dition.Our interviewarevealed that some treatments are overused and others could be applied more often. We discuss the implications of our findings from re- view of BAER assessments, then evaluate treatment methods. BAER Assessments Total BAER expenditures during the last three decades (adjusted to 1999 dollars) were greater than $83 million, with over 60 percent occurring in the 1990'x. This was due to several large Brea, their proximity to urban/wildland interface, and increased values at risk, promoting greater protection. During the last three decades, over 3.8 million ac (1.5 million ha) of Forest Service land were burned, Of that, high severity burned areax has increased from 195,000 ac (79,000 ha) in the 1970'e to over 655,000 ac (265,000 ha) in the 1990'x. Flooding and sedimentation risk is greater from areas with high severity burns. Thus more money has been spent to try to reduce the threat to downstream values. Moat of the increase in spend- ing in the 1990's was due to high profile fires that threatened urban areas (table 9). BAER teams assign erosion hazard ratings to vari- ous portions of a burned area based on local geology, soil type, topography, burn severity, expected storm duration and intensity, and local experience with postfire conditions. Improvements in erosion hazard rating could be accomplished by better fire severity mapping with infrared flights and satellite imagery after the fire (Lachowski and others 1997). These methods, though still in development, have shown promise for providing better burn area-wide severity assessment. Methods used to calculate erosion poten- tial and sediment yields were not consistent, and in some cases the estimates made could be considered unreasonable. For example, erosion rates of 1000 t ac 1 (2200 Mg ha 1) and sediment Melds of 0.1 million yda mi 2 (0.03 million mg km') were projected on several fires. Considering that our review of published literature found reported erosion rates no higher than 16b t ac 1 (370 mg ha 1) even from steep chaparral atopes (Hendricks and Johnson 1944). This suggests that assumptions about erosion potential used for those calculations are inaccurate. Uncritical review of the erosion potential estimates by the BAER team leaders must also have oceurred. Refinement of the calculation methods and better training on how to do these calculations appears warranted. Most BAER treatments were designed fora 10-year or 25-year return interval event indicating that treat- ments were designed for major storm events. Thus, the tolerance for high peakflowe and excess sediment was low. Design storm estimated peakflow changes were not well correlated with infiltration reduction (fig. 15). A 10 percent reduction in infiltration i& not likely to cause a 10,000 percent or great increase in peakflows. It is more realistic to expect that magni- tude of increase from infiltration reduction of 80 to 100 percent. From our literature review, actual in- creases in peakflowe due to wildfires can range over 3 to 4 orders of magnitude (Anderson and others 1976, Glendening and others 1961). Hibbart (1971) reported a 9,600 percent increase in peakflowe in chaparral after a severe wildfire. Although high peakflow in- creases occur due to infiltration reduction and water repellent soil conditions in some forest types, design storm peakflow estimation techniques need to be re- fined and better documented to reflect the realities of watershed response to severe wildfire. Aceording to the Burned Area Reports we collected, water repellent soil conditions are more widespread after fire than previously reported (fig. 13; DeBano and others 1998). Existing research suggests that water repellency is usually found on coarse-textured soils, especially under chaparral or other vegetation with high levels of volatile organic compounds in the litter (DeBano and others 1979b, DeBano and others 1998). Our dataset included reports of water repellent conditions across all soil and vegetation types. Unfor- tunately, the information given on the Burned Area Reports did not allow ua to analyze what methods were used to determine soil water repellent conditions (thus assessing the accuracy of the estimates) or how exten- sive the sampling was for the water repellent area determinations. These results identify a need for addi- tional research on the extent and severity of water repellent soil conditions and its affect on infiltration after wildfire in the Western United States. Quantifying the watershed degradation threat ie difficult. Threats to life and property, water quality, and soil productivity were the main reasons given for proposing BAER treatments. The more urban Forest Service Regions listed threats to property as a reason for BAER treatment 50 percent of the time. Aa devel- opment in foothill areas increases, the need to treat burned areas to reduce the riakto property andlife will likely increase as well. The role of flood plains during flood and debris flows needs to be emphasized. 44 USDA Forest Service Gen. Tech. Rep. RMRS-GTR-63.2000