Willow Creek Co Dam

Materials within and surrounding the area of Willow Creek Dam and Reservoir include Cretaceous and Paleocene sedimentary rocks, Miocene basalt flows with interlayered mudstone, siltstone and sandstone of the same age, Pleistocene terrace deposits and alluvium and terrace deposits of Holocene age.  The dam and appurtenant structures are situated in an area of Miocene basalt flows and interlayered tuffaceous mudstone, siltstone and sandstone.  Most of the older sedimentary rocks, as well as younger surficial materials occur within the upper reaches of the reservoir.  At the time investigations were conducted, the sedimentary rocks interlayered with Miocene basalt flows were refereed to as the North Platte formation.  Since that time there has been a change in nomenclature.  The subject sedimentary rocks are now called the Troublesome formation.

RegionFacilities in Great Plains | Great Plains Home Page
ProjectColorado-Big Thompson
Dam Type
ReservoirWillow Creek
WatercourseWillow Creek
Original Construction1951-1953
Modified Construction
National ID NumberCO01670
Hydrologic Unit Code

Structural Height127.0 ft
Hydraulic Height (Normal Operating Depth at Dam)95.0 ft
Top Parapet (Elevation)
Spillway Crest Elevation
Crest Elevation8140.0 ft
Crest Length1100.0 ft
Crest Width
Base Width
Volume of Dam Construction Materials
Streambed at Dam Axis8037.0 ft
Top of Exclusive Flood Control Pool (Elevation)
Top of Joint Use Pool (Elevation)
Top of Active Conservation Pool (Elevation)8130.0 ft
Top of Inactive Conservation Pool (Elevation)8117.0 ft
Top of Dead Storage Pool (Elevation)8077.0 ft

Hydraulics & Hydrology
Total Water Storage at Elevation
Maximum Water Surface Elevation
Normal Water Surface Elevation8130.0 ft
Spillway Type
Auxiliary SpillwayNo
Spillway Capacity at Elevation3200 cfs at 8132.0 ft
Auxiliary Spillway Capacity at Elevation
Uncontrolled Spillway Capacity at Elevation
Outlet Works Capacity at Elevation2405 cfs at 8132.0 ft
Diversion Capacity at Elevation
Drainage Area134.0 sq mi
Hydrometeorological Report (HMR)HMR 49
Probable Maximum Flood (PMF) Report

Contact Information
TitleArea Office Manager
OrganizationEastern Colorado Area Office
Address11056 W. County Rd 18E
CityLoveland, CO 80537-9711
Phone (Fax)970 663-3212
Phone (Office)970 667-4410
OrganizationNorthern Colorado Water Conservancy District
AddressPO Box 679
CityLoveland, CO 80539
Phone (Office)970 667-2437

Last updated: Apr 08, 2013