Lower South Platte River Study

• Contractor Name: Colorado Water Conservation Board
• Loan Projects - Doc Type: Feasibility Study

' Lower South Platte River Study
Colorado Water Conservation Board
December 2001
would be impacted by the construction of the reservoir. The reservoir would have a
' capacity of 6,600 acre-feet with a maximum normal pool at Elevation 3740. The
dam would be a zoned embankment,with a height of 40 feet and a crest length of
3,900 feet. The total cost to build the dam would be $6,830,000, which corresponds
to a cost of$1,030 per acre-foot of storage. The Harmony Ditch loops through the
reservoir site and would need to be modified, possibly by addition of a siphon
located across the shallow valley downstream of the dam.
Sterling Lateral West
' The Sterling Lateral West Reservoir site is located about 32 miles upstream of the
state line, 2.7 miles north of Crook, Colorado. The site has no distinguishing
' geologic features. The valley in the vicinity of the potential dam site has broad,
gentle slopes. The land that would be inundated by the reservoir is privately owned.
A windmill is the only structure within the reservoir basin. The reservoir would
' have a capacity of 6,900 acre-feet and a maximum normal pool at Elevation 3790.
The dam would be a zoned embankment with a height of 40 feet and a crest length
' of 3,800 feet. The reservoir could be filled by gravity from the North Sterling Outlet
Canal or by pumping from the Harmony Ditch. The contributing drainage area to
the site is 2.5 square miles. The dam would cross an intermittent stream and would
inundate wetlands delineated on USFWS mapping. The total cost to build the dam
would be $5,890,000, or$850 per acre-foot of storage.
' North Sterling Regulating Reservoir
The North Sterling Regulating Reservoir site is located 5.5 miles north of Crook,
Colorado about 32 miles upstream of the state line along the Lower South Platte
River. The site would be on private land. The reservoir would have a capacity of
' 7,600 acre-feet with a maximum normal pool at Elevation 3940. The dam would be
a zoned embankment with a height of 65 feet and a crest length of 6,100 feet. The
reservoir could be filled by gravity using the North Sterling Outlet Canal. The site
' contains wetland areas, as delineated on USFWS mapping. The contributing
drainage area at the dam site is 4.7 square miles. It would be necessary to relocate a
' road for the construction of the reservoir. The total cost of the reservoir would be
$19,800,000, which is $2,610 per acre-foot of storage.
Ramsey Draw
The site for Ramsey Draw Reservoir is located 4.5 miles northwest of Crook,
' Colorado, about 37 miles upstream of the state line along the Lower South Platte
River. The site has medium sloping abutments and occasional outcrops of slightly
cemented siltstone. The depth to the bedrock at the proposed dam axis is unknown.
GEI Consultants, Inc. 4-15 01002 Dec 2001 Lower South Platte River Study