US Bridges

CR 21 over Drainage Ditch

Good

Brazoria County, Texas · 0.30 MI E of SH 36 · Structure no. 120200AA0152001

Built
1987
38 years old
Condition
Good
inspected December 2023
Type
Culvert
Concrete
Length
23 ft
3 main spans
Daily traffic
100
2011 count
Owner
County
County Highway Agency

About this bridge

CR 21 over Drainage Ditch is a concrete culvert carrying CR 21 over Drainage Ditch in Brazoria County, Texas. It was built in 1987, so it is 38 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 vehicles a day, projected to reach 150 by 2031. The structure is 23 ft (7 m) long and 33 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesCR 21
CrossesDrainage Ditch
Location0.30 MI E of SH 36
RouteCounty Highway 21
CountyBrazoria County
StateTexas
Coordinates29.23704, -95.69796
Functional classRural Local

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 protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert7 GoodSome minor problems.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating36 US tons
Inventory rating27 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckConcrete, cast-in-place
Main spans3
Design loadUnknown
Structure length23 ft (7 m)
Longest span6 ft (1.8 m)
Deck width33 ft (10.1 m)
Roadway width31 ft (9.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (2011)
Projected traffic150 by 2031
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 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 CR 21 over Drainage Ditch built?

It was built in 1987, making it 38 years old in 2025.

What condition is CR 21 over Drainage Ditch 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 December 2023.

How much traffic does CR 21 over Drainage Ditch carry?

About 100 vehicles per day (2011 count).

How long is CR 21 over Drainage Ditch?

The structure is 23 ft (7 m) long with a longest span of 6 ft (1.8 m) and a deck 33 ft wide.

Who owns CR 21 over Drainage Ditch?

It is owned by the County Highway Agency.