US Bridges

Diggles ST over Moffett Creek

Good

Siskiyou County, California · At Newton ST · Structure no. 02C0262

Built
1988
37 years old
Condition
Good
inspected June 2024
Type
Slab
Prestressed Concrete
Length
60 ft
1 main span
Daily traffic
200
1988 count
Owner
City
City or Municipal Highway Agency

About this bridge

Diggles ST over Moffett Creek is a prestressed concrete slab carrying Diggles ST over Moffett Creek in Siskiyou County, California. It was built in 1988, so it is 37 years old, younger than the California average of 54.8 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 200 vehicles a day, roughly 5% of them trucks, projected to reach 273 by 2042. The structure is 60 ft (18.3 m) long and 28 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesDiggles ST
CrossesMoffett Creek
LocationAt Newton ST
RouteCity Street 0
Coordinates41.60714, -122.84529
Functional classUrban Local

Condition and inspection

Good

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJune 2024
Inspection intervalevery 48 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 adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating70.8 US tons
Inventory rating35.7 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20 + Mod
Structure length60 ft (18.3 m)
Longest span60 ft (18.3 m)
Deck width28 ft (8.5 m)
Roadway width27 ft (8.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic200 (1988)
Projected traffic273 by 2042
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 Diggles ST over Moffett Creek built?

It was built in 1988, making it 37 years old in 2025.

What condition is Diggles ST over Moffett Creek 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 June 2024.

How much traffic does Diggles ST over Moffett Creek carry?

About 200 vehicles per day (1988 count), of which roughly 5% are trucks.

How long is Diggles ST over Moffett Creek?

The structure is 60 ft (18.3 m) long with a longest span of 60 ft (18.3 m) and a deck 28 ft wide.

Who owns Diggles ST over Moffett Creek?

It is owned by the City or Municipal Highway Agency.