US Bridges

City ST - Mahoney over San Miguel River

Poor

San Miguel County, Colorado · 700 Ft S of SH145 · Structure no. TELLRD-MAHONEY

Built
1995
30 years old
Condition
Poor
inspected June 2024
Type
Culvert
Steel
Length
33 ft
2 main spans
Daily traffic
833
2022 count
Owner
Town / Township
Town or Township Highway Agency

About this bridge

City ST - Mahoney over San Miguel River is a steel culvert carrying City ST - Mahoney over San Miguel River in San Miguel County, Colorado. It was built in 1995, so it is 30 years old, younger than the Colorado average of 42.2 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 3 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 833 vehicles a day, roughly 2% of them trucks, projected to reach 950 by 2042. The structure is 33 ft (10.1 m) long and 69 ft wide. If it were closed, the detour would be 100 mi (161 km).

CarriesCity ST - Mahoney
CrossesSan Miguel River
Location700 Ft S of SH145
RouteCity Street 0
Coordinates37.9383, -107.82158
Functional classRural Local

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
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Culvert3 SeriousLoss of section, deterioration, spalling or scour have seriously affected primary structural components.
Last inspectionJune 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourFoundations stable; action required to protect exposed foundations
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry6: Equal to present minimum criteria
Waterway adequacy4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating110.1 US tons
Inventory rating110.1 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans2
Design loadHS 20
Structure length33 ft (10.1 m)
Longest span14 ft (4.4 m)
Deck width69 ft (20.9 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic833 (2022)
Projected traffic950 by 2042
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed100 mi (161 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerTown or Township Highway Agency
Maintained byTown or Township Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedDeck rehabilitation with only incidental widening
Estimated improvement cost$1.5 million (2020 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was City ST - Mahoney over San Miguel River built?

It was built in 1995, making it 30 years old in 2025.

What condition is City ST - Mahoney over San Miguel River 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 June 2024.

How much traffic does City ST - Mahoney over San Miguel River carry?

About 833 vehicles per day (2022 count), of which roughly 2% are trucks.

How long is City ST - Mahoney over San Miguel River?

The structure is 33 ft (10.1 m) long with a longest span of 14 ft (4.4 m) and a deck 69 ft wide.

Who owns City ST - Mahoney over San Miguel River?

It is owned by the Town or Township Highway Agency.