Middle is an earth dam located in Clatsop County, Oregon, built in 1940. It carries a High hazard potential classification and has a fair condition assessment.

Hazard potentialHighFailure would probably cost lives
ConditionFair2nd of 4 ratings
Emergency action planOn file
Last inspection08/18/2020
Height39 ft
Built194086 years ago

Dam profile

NID height · 39 ft
39 FT TWO-STORY HOUSEMEDIAN U.S. DAM · 24 FT

39 ft tall and 410 ft long, taller than 85% of U.S. dams with a recorded height. Height is drawn to scale against a two-story house, about 25 ft; the profile is a generic embankment section and the water level is illustrative.

About Middle

The primary purpose of Middle 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 Astoria (local government). It impounds the Bear Creek near Svensen.

The dam stands 39 feet tall and stretches 410 feet across, creates a reservoir covering 9 acres, has a maximum storage capacity of 168 acre-feet, and collects water from a drainage area of 4 square miles. Completed in 1940, 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 08/18/2020.

At 39 feet, this dam is taller than 85% of dams nationwide.

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

StateOregon
CountyClatsop
Nearest CitySvensen
River/StreamBear Creek
Coordinates46.09499, -123.61719

Physical Characteristics

Dam TypeEarth
NID Height39 ft
Dam Height39 ft
Dam Length410 ft
Year Completed1940 (86 years old)

Storage & Hydraulics

NID Storage168 acre-ft
Max Storage168 acre-ft
Normal Storage168 acre-ft
Surface Area9 acres
Drainage Area4 sq mi
Max Discharge50 cfs

Ownership & Safety

PurposeWater Supply
OwnerCity of Astoria
Owner TypeLocal Government
Hazard ClassificationHigh
Condition AssessmentFair
Last Inspection08/18/2020
Emergency Action PlanYes

Identifiers

NID IDOR00135
Federal IDOR00135
More InfoState Dam Safety Program