US Bridges

Pr 100 over Intracoastal Waterway

Fair

Cameron County, Texas · Qn Isabella Causeway · Structure no. 210310033104005

Built
1974
51 years old
Condition
Fair
inspected April 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
12,510 ft
3 main spans
Daily traffic
18,777
2024 count
Owner
State
State Highway Agency

About this bridge

Pr 100 over Intracoastal Waterway is a steel continuous stringer/multi-beam or girder carrying Pr 100 over Intracoastal Waterway in Cameron County, Texas. It was built in 1974, so it is 51 years old, older than the Texas average of 44.4 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 18,777 vehicles a day, roughly 3% of them trucks, projected to reach 22,730 by 2033. The structure is 12,510 ft (3,813 m) long and 68 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesPr 100
CrossesIntracoastal Waterway
LocationQn Isabella Causeway
RouteState Highway 100
CountyCameron County
StateTexas
Coordinates26.08644, -97.18005
Functional classUrban Other Principal Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour evaluation has not been made
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating50 US tons
Inventory rating30 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3 (+147 approach)
Design loadHS 20
Structure length12,510 ft (3,813 m)
Longest span310 ft (94.5 m)
Deck width68 ft (20.7 m)
Roadway width63 ft (19.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic18,777 (2024)
Projected traffic22,730 by 2033
Trucks3%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusPossibly eligible for the National Register; requires further investigation
Work proposedNone recorded
Estimated improvement cost—
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was Pr 100 over Intracoastal Waterway built?

It was built in 1974, making it 51 years old in 2025.

What condition is Pr 100 over Intracoastal Waterway in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in April 2023.

How much traffic does Pr 100 over Intracoastal Waterway carry?

About 18,777 vehicles per day (2024 count), of which roughly 3% are trucks.

How long is Pr 100 over Intracoastal Waterway?

The structure is 12,510 ft (3,813 m) long with a longest span of 310 ft (94.5 m) and a deck 68 ft wide.

Who owns Pr 100 over Intracoastal Waterway?

It is owned by the State Highway Agency.