FLOOD07072

• County: Statewide
• Stream Name: South Platte
• Basin: South Platte
• Title: Water and Related Land Resources Management Study Volume IIIC - Appendix A
• Date: 7/14/1980
• Prepared For: South Platte and Tributaries
• Prepared By: CWCB
• Floodplain - Doc Type: Flood Mitigation/Flood Warning/Watershed Restoration

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this total, 19,982 square miles lie downstream from Chatfield

Dam. Topography of the basin is about one-third mountainous and

two-thirds plains area. A basin map is shown on plate 1. Topo-

graphy of the South Platte River in the headwaters area is

extremely rugged with slopes up to several hundred feet per mile.

Stream flow in this region is confined to well defined channels

and narrow canyon walls and is typical of the headwaters area of

most of the left-bank tributaries of the South Platte located

along the eastern slope of the Rockies. At the mouth of the South

Platte Canyon, the flow regime changes abruptly to the typical high

plains geometry characteristic of most of the South Platte right-

bank tributaries. Stream slopes in the plains are as much as about

40 feet per mile and channels are normally well defined with adja-

cent overbank areas relatively flat. Downstream from Chatfield

to Greeley, Colorado, several mountain tributaries flow into the

South Platte along the left bank and numerous small to moderate

size high plains tributaries enter the stream along the right bank.

Downstream from Greeley to the Colorado-Nebraska State line, the

South Platte flows in an easterly direction. The tributaries

joining the main stream in this reach from both right and left

banks drain high plains areas. An inventory of the named tribu-

taries which enter the South Platte between Chatfield Dam and

the Colorado-Nebraska State line is presented in table 1.

Location of each tributary is shown on the basin map on plate 1.

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