US Bridges

Nat Trails HWY over Iliad Ditch

Poor

San Bernardino County, California · 23.2 MI E Kelbaker RD · Structure no. 54C0317

Built
1930
95 years old, rebuilt 1953
Condition
Poor
inspected October 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
59 ft
3 main spans
Daily traffic
502
2018 count
Owner
County
County Highway Agency

About this bridge

Nat Trails HWY over Iliad Ditch is a wood or timber stringer/multi-beam or girder carrying Nat Trails HWY over Iliad Ditch in San Bernardino County, California. It was built in 1930 and reconstructed in 1953, so it is 95 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. Its operating status is: open, would be posted or closed except for temporary shoring.

It carries about 502 vehicles a day, roughly 30% of them trucks, projected to reach 574 by 2042. The structure is 59 ft (18 m) long and 28 ft wide. If it were closed, the detour would be 39.8 mi (64 km).

CarriesNat Trails HWY
CrossesIliad Ditch
Location23.2 MI E Kelbaker RD
RouteCounty Highway 0
Coordinates34.70175, -115.29597
Functional classRural Major 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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 12 months
Operating statusOpen, would be posted or closed except for temporary shoring
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation2: Basically intolerable, requiring high priority of replacement
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating35.1 US tons
Inventory rating10.4 US tons

Structure

MaterialWood or Timber
DeckConcrete, cast-in-place
Main spans3
Design loadUnknown
Structure length59 ft (18 m)
Longest span19 ft (5.8 m)
Deck width28 ft (8.6 m)
Roadway width26 ft (8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic502 (2018)
Projected traffic574 by 2042
Trucks30%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed39.8 mi (64 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$595,000 (2025 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Nat Trails HWY over Iliad Ditch built?

It was built in 1930, making it 95 years old in 2025. It was reconstructed in 1953.

What condition is Nat Trails HWY over Iliad Ditch 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 October 2024.

How much traffic does Nat Trails HWY over Iliad Ditch carry?

About 502 vehicles per day (2018 count), of which roughly 30% are trucks.

How long is Nat Trails HWY over Iliad Ditch?

The structure is 59 ft (18 m) long with a longest span of 19 ft (5.8 m) and a deck 28 ft wide.

Who owns Nat Trails HWY over Iliad Ditch?

It is owned by the County Highway Agency.