FLOOD06593 - Laserfiche WebLink

Home Browse Search

. ~ ~ > ~ c 0 ~ ~ 5 ~ r co m c 0 E ~ ~ E ~ ~ ro ~ c ~~ ~ ~ 0 ~ c ~ ~ ~ ~o m ~a u c 0 ~ W3 Q >0 ~ g~ ~ ~ <~ ~ ro ~ ~ ~ ,- > !.. GENERAL CONDITIONS , " i! i: I: " , I , I i ; Stream and Val ley Characteristics The Big Thompson River flows easterly from the high mountains of the Colorado Front Range in Rocky Mountain National Park to join the South Platte River southwest of Greeley, Colorado. Basin elevations vary from 13,000 feet, mean sea level (m.s.I.) at the source to about 4,700 feet, m.s.l. at the mouth. Eight mi les west of Loveland the river leaves the mountain canyons, passes through a short reach of foothi lis and enters the high plains area. Major tributaries are Buckhorn Creek which drains from the north and enters just west of Loveland, and the Little Thompson River which joins the parent stream from the right bank near its mouth. The total drainage area above the mouth is 830 square miles. The reduced drainage area upstream from Loveland is 509 square mi les, as shown on the inside front cover of this report. The portion of the Big Thompson River studied in this report extends from the eastern edge of the foothi I Is to a point 8 mi les downstream. The Colorado and Southern Rai Iway crosses the flood plain south of Loveland near the midpoint of the study reach. The flood plain is fairly flat and averages one-half mile in width. The channel is moderately sinuous, the 8 mile length of river within the study reach covers a valley distance of only 6 mi les. Channel dimensions vary appreciably from 4 to 10 feet in depth and 50 to 200 feet in width. The streambed is gravelly and has an average slope of 19 feet per mile through the study reach. The banks of the stream are vegetat~dwith weeds, wi Ilows and an occasional clump of trees. The photographs on the following pages show the stream characteristics along the Big Thompson River through the study reach. 3 4