US Bridges

21st ST over East Twin Creek Channel

Poor

San Bernardino County, California · 0.55 MI E Waterman Ave · Structure no. 54C0535

Built
1961
64 years old
Condition
Poor
inspected January 2024
Type
Tee Beam
Concrete
Length
54 ft
1 main span
Daily traffic
5,814
2016 count
Owner
City
City or Municipal Highway Agency

About this bridge

21st ST over East Twin Creek Channel is a concrete tee beam carrying 21st ST over East Twin Creek Channel in San Bernardino County, California. It was built in 1961, so it is 64 years old, older than the California average of 54.8 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 5,814 vehicles a day, roughly 2% of them trucks, projected to reach 6,973 by 2044. The structure is 54 ft (16.5 m) long and 49 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
Carries21st ST
CrossesEast Twin Creek Channel
Location0.55 MI E Waterman Ave
RouteCity Street 0
CountySan Bernardino County
StateCalifornia
Coordinates34.13395, -117.26924
Functional classUrban Collector

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
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection9 ExcellentNo problems noted.
Last inspectionJanuary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment5: Somewhat better than minimum adequacy to tolerate being left in place as is
Operating rating93.9 US tons
Inventory rating56.4 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length54 ft (16.5 m)
Longest span51 ft (15.5 m)
Deck width49 ft (14.9 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,814 (2016)
Projected traffic6,973 by 2044
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal 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 21st ST over East Twin Creek Channel built?

It was built in 1961, making it 64 years old in 2025.

What condition is 21st ST over East Twin Creek Channel 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 January 2024.

How much traffic does 21st ST over East Twin Creek Channel carry?

About 5,814 vehicles per day (2016 count), of which roughly 2% are trucks.

How long is 21st ST over East Twin Creek Channel?

The structure is 54 ft (16.5 m) long with a longest span of 51 ft (15.5 m) and a deck 49 ft wide.

Who owns 21st ST over East Twin Creek Channel?

It is owned by the City or Municipal Highway Agency.