US Bridges

Sidney RD over Port Allen Lock

Poor

Iberville Parish, Louisiana · 0.01 Mi. N. of LA77 · Structure no. 612430223912371

Built
1966
59 years old
Condition
Poor
inspected August 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
126 ft
5 main spans
Daily traffic
400
2019 count
Owner
County
County Highway Agency

About this bridge

Sidney RD over Port Allen Lock is a steel stringer/multi-beam or girder carrying Sidney RD over Port Allen Lock in Iberville Parish, Louisiana. It was built in 1966, so it is 59 years old, older than the Louisiana average of 43 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 400 vehicles a day, projected to reach 440 by 2039. The structure is 126 ft (38.4 m) long and 30 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesSidney RD
CrossesPort Allen Lock
Location0.01 Mi. N. of LA77
RouteCounty Highway 0
CountyIberville Parish
StateLouisiana
Coordinates30.37162, -91.39507
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating28.9 US tons
Inventory rating22.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckOpen grating
Main spans5
Design loadHS 20
Structure length126 ft (38.4 m)
Longest span45 ft (13.7 m)
Deck width30 ft (9 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic400 (2019)
Projected traffic440 by 2039
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.1 mi (13 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 Sidney RD over Port Allen Lock built?

It was built in 1966, making it 59 years old in 2025.

What condition is Sidney RD over Port Allen Lock 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 August 2024.

How much traffic does Sidney RD over Port Allen Lock carry?

About 400 vehicles per day (2019 count).

How long is Sidney RD over Port Allen Lock?

The structure is 126 ft (38.4 m) long with a longest span of 45 ft (13.7 m) and a deck 30 ft wide.

Who owns Sidney RD over Port Allen Lock?

It is owned by the County Highway Agency.