Structure 121020098101028 · Harris County, TX

Nasa RD 1 over FM 270 & Cow Bayou

Carries Nasa RD 1 over FM 270 & Cow Bayou, 1.3 Mi NE Of SH 3.

Overall conditionGood

Set by its lowest-rated component: Deck and Superstructure and Substructure at 7 of 9.

How ratings work
Decksets the rating7/9 · Good
Superstructuresets the rating7/9 · Good
Substructuresets the rating7/9 · Good
Channelnot part of overall8/9 · Very Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT978 FT OVERALL200 FT0ELEVATION · LENGTHS TO SCALE
Deck 7/9Superstructure 7/9Substructure 7/9

978 ft end to end, longest span 114 ft: about 2.7 football fields. Lengths and the semi-truck on the deck are drawn to the same scale. Each part is colored by its latest inspection rating. The inventory records lengths but not heights or the layout of the shorter spans, so those are drawn as typical for a multi-beam bridge.

Built200818 years old
Length978.0 ft298.1 m
Daily traffic41,441counted 2023
Last inspectedNovember 2024every 24 months

Location

StateTexas
CountyHarris
Location1.3 Mi NE Of SH 3
CarriesNasa RD 1
CrossesFM 270 & Cow Bayou
Coordinates29.54643, -95.10487

Physical Characteristics

MaterialPrestressed Concrete
DesignStringer/Multi-beam
Total Length978.0 ft (298.1 m)
Max Span113.8 ft (34.7 m)
Deck Width107.6 ft (32.8 m)
Deck Area9777.7 sq m
Main Spans9
Year Built2008

Traffic

Avg Daily Traffic41,441 (2023)
Truck Traffic8%
Lanes On Bridge6
Lanes Under Bridge9

Inspection & Ownership

Last InspectionNovember 2024
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour Critical6 — Scour calculated, stable
Structure Number121020098101028

How Bridge Ratings Work

Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."

0Failed
1Imminent failure
2Critical
3Serious
4Poor
5Fair
6Satisfactory
7Good
8Very good
9Excellent
Good · lowest component 7–9
Fair · lowest component 5–6
Poor · lowest component 0–4

A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.

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