US Bridges

Groshong Road over Ditch

Poor

Linn County, Oregon · 3.0 MI NW Millersburg · Structure no. 12772 031100148

Built
1959
66 years old
Condition
Poor
inspected October 2024
Type
Channel Beam
Concrete
Length
49 ft
3 main spans
Daily traffic
206
2021 count
Owner
County
County Highway Agency

About this bridge

Groshong Road over Ditch is a concrete channel beam carrying Groshong Road over Ditch in Linn County, Oregon. It was built in 1959, so it is 66 years old, older than the Oregon average of 49.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 206 vehicles a day, roughly 10% of them trucks, projected to reach 288 by 2041. The structure is 49 ft (14.9 m) long and 25 ft wide. If it were closed, the detour would be 6.8 mi (11 km).

Location

Open in Google Maps
CarriesGroshong Road
CrossesDitch
Location3.0 MI NW Millersburg
RouteCounty Highway C0311
CountyLinn County
StateOregon
Coordinates44.70639, -123.10173
Functional classRural Local

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating42.1 US tons
Inventory rating32.5 US tons

Structure

Structure typeChannel Beam
MaterialConcrete
DeckConcrete, precast panels
Main spans3
Design loadH 20
Structure length49 ft (14.9 m)
Longest span19 ft (5.8 m)
Deck width25 ft (7.7 m)
Roadway width23 ft (6.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic206 (2021)
Projected traffic288 by 2041
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.8 mi (11 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Groshong Road over Ditch built?

It was built in 1959, making it 66 years old in 2025.

What condition is Groshong Road over Ditch in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in October 2024.

How much traffic does Groshong Road over Ditch carry?

About 206 vehicles per day (2021 count), of which roughly 10% are trucks.

How long is Groshong Road over Ditch?

The structure is 49 ft (14.9 m) long with a longest span of 19 ft (5.8 m) and a deck 25 ft wide.

Who owns Groshong Road over Ditch?

It is owned by the County Highway Agency.