Prospect

Prospect is an earth dam located in Weld County, Colorado, built in 1914. It carries a Significant hazard potential classification and has a satisfactory condition assessment.

About Prospect

The primary purpose of Prospect is irrigation. The dam stores and diverts water for agricultural irrigation, supporting farming operations in the surrounding area. The dam is owned by Henrylyn Irrigation District (private). It impounds the Lost Creek-tr near Roggen.

The dam stands 45 feet tall and stretches 5,301 feet across, creates a reservoir covering 398 acres, has a maximum storage capacity of 9,299 acre-feet, and collects water from a drainage area of 9 square miles. Completed in 1914, the structure is over a century old.

This dam has a significant hazard potential classification, meaning that a failure could cause significant economic damage — flooding roads, bridges, or property downstream — but is not expected to result in loss of life. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 06/18/2021.

At 45 feet, this dam is taller than 91% of dams nationwide.

Search for dams near your address to see all dams in your area with hazard classifications and safety data.

Significant HazardSatisfactory ConditionEmergency Action Plan: Yes

Location

StateColorado
CountyWeld
Nearest CityRoggen
River/StreamLost Creek-tr
Coordinates40.01777, -104.50859

Physical Characteristics

Dam TypeEarth
NID Height45 ft
Dam Height44 ft
Dam Length5,301 ft
Year Completed1914 (112 years old)

Storage & Hydraulics

NID Storage9,299 acre-ft
Max Storage9,299 acre-ft
Normal Storage6,368 acre-ft
Surface Area398 acres
Drainage Area9 sq mi
Max Discharge14,700 cfs
Spillway TypeUncontrolled

Ownership & Safety

PurposeIrrigation
OwnerHENRYLYN IRRIGATION DISTRICT
Owner TypePrivate
Hazard ClassificationSignificant
Condition AssessmentSatisfactory
Last Inspection06/18/2021
Emergency Action PlanYes

Identifiers

NID IDCO01106
Federal IDCO01106
More InfoState Dam Safety Program

Nearby Dams