US Bridges

SH 9 Ml over Middle Fk S.Platte Rvr

Fair

Park County, Colorado · 9.7 MI SW of Fairplay 285 · Structure no. H-13-S

Built
1951
74 years old
Condition
Fair
inspected December 2023
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
38 ft
2 main spans
Daily traffic
2,300
2020 count
Owner
State
State Highway Agency

About this bridge

SH 9 Ml over Middle Fk S.Platte Rvr is a wood or timber stringer/multi-beam or girder carrying SH 9 Ml over Middle Fk S.Platte Rvr in Park County, Colorado. It was built in 1951, so it is 74 years old, older than the Colorado average of 42.2 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.

It carries about 2,300 vehicles a day, roughly 10% of them trucks, projected to reach 3,496 by 2040. The structure is 38 ft (11.7 m) long and 26 ft wide. If it were closed, the detour would be 16.8 mi (27 km).

Location

Open in Google Maps
CarriesSH 9 Ml
CrossesMiddle Fk S.Platte Rvr
Location9.7 MI SW of Fairplay 285
RouteState Highway 9B
CountyPark County
StateColorado
Coordinates39.11111, -105.89184
Functional classRural Minor Arterial

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionDecember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48.2 US tons
Inventory rating34.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans2
Design loadH 15
Structure length38 ft (11.7 m)
Longest span18 ft (5.6 m)
Deck width26 ft (7.8 m)
Roadway width25 ft (7.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,300 (2020)
Projected traffic3,496 by 2040
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed16.8 mi (27 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 SH 9 Ml over Middle Fk S.Platte Rvr built?

It was built in 1951, making it 74 years old in 2025.

What condition is SH 9 Ml over Middle Fk S.Platte Rvr 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 December 2023.

How much traffic does SH 9 Ml over Middle Fk S.Platte Rvr carry?

About 2,300 vehicles per day (2020 count), of which roughly 10% are trucks.

How long is SH 9 Ml over Middle Fk S.Platte Rvr?

The structure is 38 ft (11.7 m) long with a longest span of 18 ft (5.6 m) and a deck 26 ft wide.

Who owns SH 9 Ml over Middle Fk S.Platte Rvr?

It is owned by the State Highway Agency.