Floodplain Information Report Volume 2 White River from Rio Blanco Lake to the Utah-Colorado State Line

t 1 C t t 1 TABLE 2 WO MEEKER GAGE (2.5 MI U/S OF MEEKER)* 1024 miZ a W1 ABOVE PICEANCE CR 1204 mil b W2 BELOW PICEANCE CR 1856 miZ b W3 ABOVE YELLOW CR 2018 miZ b W4 BELOW YELLOW CR 2280 miZ b W5 BELOW WOLF CR 2460 miZ a W6 BELOW BOISE CR (GAGE SITE) 2530 miZ a W7 BELOW SPRING CR 2620 miZ b W8 ABOVE DOUGLAS CR 2880 miZ a W9 BELOW RANGELY AT D/S LIMIT OF FEMA STUDY 3300 miZ a W10 STATELINE 3552 miZ b Sources of Drainage Areas a Determined from published information and USGS gage values b Determined from upstream USGS gage information combined with planimetering * Not in study reach Figure 4 shows the study reach and each of the hydrologic analysis points listed in Table 2. 2.5 Flood Characteristics Major flooding in the White River basin has been primarily the result of rapid snowmelt beginning as early as late April. Snowmelt flooding can continue into early July. Flooding can also occur from rainfall on snowmelt and from ice jams in late winter or early spring. Due to the small areal extent and limited duration of thunderstorms, they do not typically constitute a major flood threat on streams as large as the White River. They do, however pose a problem for some of the smaller tributaries in the White River basin. Snowmelt flooding is characterized by moderate peak flows, large volume of runoff, long duration, and diurnal fluctuation of flow. Flooding from general rainfall alone, though uncommon on the White River, is characterized by high peak flows and moderate duration of floodflows. Historically, ice jams, rain on snow, and local thunderstorms have caused the greatest flooding around Rangely. Snowmelt floods of 1983 and 1984 produced 100 -year flows at 7