FLOOD10215 - Laserfiche WebLink

Home Browse Search

· Other considerations for predicting snowmelt runoff include: - Development of a daily unit discharge value for the selected forecast stations which is based on past snowpack water content, temperature trends, and recorded discharges; - A working knowledge of past snowmelt runoff characteristics for the selected station; - An understanding that a daily snowpack melt rate of 0.5 to 1.0 inches is considered to be normal to slightly above normal; and - An understanding that a daily snowpack melt rate of 2.0 inches or more is considered to be rapid. The CWCB's 1995 snowmelt modeling procedure was based on the elements, parameters, and characteristics of the 1984, 1993, and 1995 snowmelt flooding events. The CWCB staff selected ten flood forecast stations/locations to assist Colorado flood alert users with an awareness of what could be expected during the days and weeks for the 1995 snowmelt runoff season. The snowmelt runoff time is traditionally between May 15th and July 4th. The ten selected stations/locations for monitoring the 1995 flood threat were: . Colorado River at the Colorado-Utah stateline . Gunnison River at Delta, Colorado . Gunnison River at Gunnison, Colorado . North Fork Gunnison River at Somerset, Colorado . Roaring Fork River at Glenwood Springs, Colorado . Arkansas River at Wellsville(Salida), Colorado . Dolores River at Dolores, Colorado . Animas River at Durango, Colorado . Rio Grande at Del Norte, Colorado . Yampa River at Steamboat Springs, Colorado For the flood forecast modelling procedure, the basic daily flood forecasting data was inputed into a spreadsheet program (Quattro Pro) and was then plotted to display the data graphically. These graphical presentations were in the form of line charts. During the 1995 peak runoff, one to two day flood peak discharges projections were made which were based on the 1984 and 1993 unit runoff values, the leading graphical curve shape of the 1995 existing runoff pattern and the 7- day temperature forecast. All previously made 24 hour forecasts were adjusted to reflect real time data for that period as indicated by the recorded stream flow values at the selected forecast stations. The final 1995 daily values for the snowpack water content (in inches of water), the daily temperature (in degree-F.), and the recorded gaged stream flow (in cfs) are presented in the attached charts for the selected locations.