US Bridges

CR 305 (mapes Rd) over Hartson Slough

FairPosted for load

Lassen County, California · 0.4 MI E/O RD 303 · Structure no. 07C0040

Built
1978
47 years old
Condition
Fair
inspected August 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
46 ft
2 main spans
Daily traffic
100
1976 count
Owner
County
County Highway Agency

About this bridge

CR 305 (mapes Rd) over Hartson Slough is a wood or timber stringer/multi-beam or girder carrying CR 305 (mapes Rd) over Hartson Slough in Lassen County, California. It was built in 1978, so it is 47 years old, younger than the California average of 54.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. Its operating status is: posted for load restriction.

It carries about 100 vehicles a day, roughly 10% of them trucks, projected to reach 272 by 2041. The structure is 46 ft (14 m) long and 28 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesCR 305 (mapes Rd)
CrossesHartson Slough
Location0.4 MI E/O RD 303
RouteCounty Highway 0
CountyLassen County
StateCalifornia
Coordinates40.32238, -120.36219
Functional classRural Minor Collector

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2024
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating5.7 US tons
Inventory rating0 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckCorrugated steel
Main spans2
Design loadUnknown
Structure length46 ft (14 m)
Longest span23 ft (6.9 m)
Deck width28 ft (8.5 m)
Roadway width28 ft (8.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (1976)
Projected traffic272 by 2041
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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 305 (mapes Rd) over Hartson Slough built?

It was built in 1978, making it 47 years old in 2025.

What condition is CR 305 (mapes Rd) over Hartson Slough in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in August 2024.

How much traffic does CR 305 (mapes Rd) over Hartson Slough carry?

About 100 vehicles per day (1976 count), of which roughly 10% are trucks.

How long is CR 305 (mapes Rd) over Hartson Slough?

The structure is 46 ft (14 m) long with a longest span of 23 ft (6.9 m) and a deck 28 ft wide.

Who owns CR 305 (mapes Rd) over Hartson Slough?

It is owned by the County Highway Agency.