Monarch Lake
Monarch Lake is an earth dam located in Grand County, Colorado, built in 1929. It carries a High hazard potential classification.
About Monarch Lake
The primary purpose of Monarch Lake is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Usda Fs (federal). It impounds the Arapaho Creek near Hot Sulphur Spgs.
The dam stands 25 feet tall and stretches 1,005 feet across, has a maximum storage capacity of 2,000 acre-feet, and collects water from a drainage area of 47 square miles. Completed in 1929, the structure is well-established, with more than 75 years of service.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Notably, no emergency action plan is currently on file for this high-hazard dam. The most recent inspection on record was 09/02/2020.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Colorado dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Colorado |
| County | Grand |
| Nearest City | Hot Sulphur Spgs |
| River/Stream | Arapaho Creek |
| Coordinates | 40.10920, -105.74780 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 25 ft |
| Dam Height | 18 ft |
| Dam Length | 1,005 ft |
| Year Completed | 1929 (97 years old) |
Storage & Hydraulics
| NID Storage | 2,000 acre-ft |
| Max Storage | 2,000 acre-ft |
| Normal Storage | 950 acre-ft |
| Drainage Area | 47 sq mi |
| Max Discharge | 3,300 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | USDA FS |
| Owner Type | Federal |
| Hazard Classification | High |
| Condition Assessment | Not Rated |
| Last Inspection | 09/02/2020 |
| Emergency Action Plan | No |
Identifiers
| NID ID | CO00714 |
| Federal ID | CO00714 |
| More Info | State Dam Safety Program |