Quincy
Quincy is an earth dam located in Arapahoe County, Colorado, built in 1974. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Quincy
The primary purpose of Quincy is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by City Of Aurora (local government). It impounds the West Toll Gate Creek near Aurora.
The dam stands 73 feet tall and stretches 2,432 feet across, creates a reservoir covering 155 acres, has a maximum storage capacity of 4,560 acre-feet, and collects water from a drainage area of 4 square miles. Completed in 1974, the structure is well into its service life at over 50 years old.
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 07/12/2022.
At 73 feet, this dam is taller than 97% of all dams in the United States.
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 | Arapahoe |
| Nearest City | Aurora |
| River/Stream | West Toll Gate Creek |
| Coordinates | 39.63667, -104.78057 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 73 ft |
| Dam Height | 70 ft |
| Dam Length | 2,432 ft |
| Year Completed | 1974 (52 years old) |
Storage & Hydraulics
| NID Storage | 4,560 acre-ft |
| Max Storage | 4,560 acre-ft |
| Normal Storage | 2,800 acre-ft |
| Surface Area | 155 acres |
| Drainage Area | 4 sq mi |
| Max Discharge | 27,000 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Water Supply |
| Owner | CITY OF AURORA |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 07/12/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CO00104 |
| Federal ID | CO00104 |
| More Info | State Dam Safety Program |