Pleasant Valley
Pleasant Valley is an earth dam located in Boulder County, Colorado, built in 1868. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Pleasant Valley
The primary purpose of Pleasant Valley is irrigation. The dam stores and diverts water for agricultural irrigation, supporting farming operations in the surrounding area. The dam is owned by Pleasant Valley Reservoir, Fish & Ditch Co. (boden (private). It impounds the St. Vrain Creek-os near Longmont.
The dam stands 19 feet tall and stretches 2,900 feet across, creates a reservoir covering 334 acres, has a maximum storage capacity of 4,707 acre-feet, and collects water from a drainage area of 3 square miles. Completed in 1868, the structure is one of the older dams in the region, with over a century and a half 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. 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 06/10/2022.
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 | Boulder |
| Nearest City | Longmont |
| River/Stream | St. Vrain Creek-os |
| Coordinates | 40.22341, -105.12299 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 19 ft |
| Dam Height | 19 ft |
| Dam Length | 2,900 ft |
| Year Completed | 1868 (158 years old) |
Storage & Hydraulics
| NID Storage | 4,707 acre-ft |
| Max Storage | 4,707 acre-ft |
| Normal Storage | 2,915 acre-ft |
| Surface Area | 334 acres |
| Drainage Area | 3 sq mi |
| Max Discharge | 2,403 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Irrigation |
| Owner | PLEASANT VALLEY RESERVOIR, FISH & DITCH CO. (BODEN |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 06/10/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CO00182 |
| Federal ID | CO00182 |
| More Info | State Dam Safety Program |