US Bridges

IH 45 over Alligator Crk N1 Trib

Good

Montgomery County, Texas · 0.20 M North of SH 105 · Structure no. 121700067508228

Built
2012
13 years old
Condition
Good
inspected October 2024
Type
Culvert
Concrete
Length
51 ft
5 main spans
Daily traffic
100,731
2020 count
Owner
State
State Highway Agency

About this bridge

IH 45 over Alligator Crk N1 Trib is a concrete culvert carrying IH 45 over Alligator Crk N1 Trib in Montgomery County, Texas. It was built in 2012, so it is 13 years old, younger than the Texas average of 44.4 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 100,731 vehicles a day, roughly 16% of them trucks, projected to reach 104,830 by 2031. The structure is 51 ft (15.5 m) long.

CarriesIH 45
CrossesAlligator Crk N1 Trib
Location0.20 M North of SH 105
RouteInterstate 45
StateTexas
Coordinates30.31759, -95.47244
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating60 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans5
Design loadHS 20
Structure length51 ft (15.5 m)
Longest span9 ft (2.7 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100,731 (2020)
Projected traffic104,830 by 2031
Trucks16%
Lanes on structure16
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 IH 45 over Alligator Crk N1 Trib built?

It was built in 2012, making it 13 years old in 2025.

What condition is IH 45 over Alligator Crk N1 Trib in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in October 2024.

How much traffic does IH 45 over Alligator Crk N1 Trib carry?

About 100,731 vehicles per day (2020 count), of which roughly 16% are trucks.

How long is IH 45 over Alligator Crk N1 Trib?

The structure is 51 ft (15.5 m) long with a longest span of 9 ft (2.7 m).

Who owns IH 45 over Alligator Crk N1 Trib?

It is owned by the State Highway Agency.