What is the minimum antecedent rainfall, in inches, needed to initiate debris f lows? How much rainfall, in inches, did the City of Boulder receive in the 7-day period of September 9 15, 2013? – How did travel distance of flows that initiated in or entered channels compare to flows that did not interact with channels? What percentage of debris flows occurred on south- and east-facing slopes? Which ecological zones experienced the greatest number of debris flows? Slope aspect was an important control on debris flow distribution; what is the key ingredient required to increase the susceptibility of north-facing slopes to debris flows? Debris flows along the west coast of the United States (e.g., the Coast Range of Oregon) are widespread about every years, while in the Colorado Front Range return periods for wide-spread debris-flow events are on the order of years or more.
What is the minimum antecedent rainfall, in inches, needed to initiate debris f lows? How much rainfall, in inches, did the City of Boulder receive in the 7-day period of September 9 – 15, 2013? How did travel distance of flows that initiated in or entered channels compare to flows that did not interact with channels? What percentage of debris flows occurred on south- and east-facing slopes? Which ecological zones experienced the greatest number of debris flows? Slope aspect was an important control on debris flow distribution; what is the key ingredient required to increase the susceptibility of north-facing slopes to debris flows? Debris flows along the west coast of the United States (e.g., the Coast Range of Oregon) are widespread about every years, while in the Colorado Front Range return periods for wide-spread debris-flow events are on the order of years or more.