Development No. 1 Dam
Development No. 1 Dam is a concrete dam located in Multnomah County, Oregon, built in 1929. It carries a High hazard potential classification and has a fair condition assessment.
About Development No. 1 Dam
The primary purpose of Development No. 1 Dam 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 Portland Oregon (local government). It impounds the Bull Run River near Troutdale, Or.
The dam stands 200 feet tall and stretches 970 feet across, creates a reservoir covering 386 acres, has a maximum storage capacity of 33,760 acre-feet, and collects water from a drainage area of 74 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. Its condition is rated fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. An emergency action plan is in place for this dam. The most recent inspection on record was 05/24/2022.
At 200 feet, this dam is taller than 99% 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 Oregon 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 | Oregon |
| County | Multnomah |
| Nearest City | Troutdale, Or |
| River/Stream | Bull Run River |
| Coordinates | 45.48180, -122.08230 |
Physical Characteristics
| Dam Type | Concrete |
| NID Height | 200 ft |
| Dam Height | 200 ft |
| Dam Length | 970 ft |
| Year Completed | 1929 (97 years old) |
Storage & Hydraulics
| NID Storage | 33,760 acre-ft |
| Max Storage | 33,760 acre-ft |
| Normal Storage | 26,640 acre-ft |
| Surface Area | 386 acres |
| Drainage Area | 74 sq mi |
| Max Discharge | 21,000 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Water Supply |
| Owner | City of Portland Oregon |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 05/24/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | OR00327 |
| Federal ID | OR00327 |
| More Info | State Dam Safety Program |