County profile · official public datasets

Broomfield County, CO

66 public highway bridges tracked in the FHWA National Bridge Inventory: 42.4% rated Good, 56.1% Fair, 1.5% Poor.

66
Public bridges: 42.4%
Good condition: 1.5%
Poor condition

The verdict

According to the Federal Highway Administration's 2024 National Bridge Inventory.

Broomfield County pairs a top-quartile lowest Poor-condition share among rated counties in the state with a newer average build year than the state inventory.

Top 14%
lowest Poor share in state: 1.5%
Poor-condition share: 66
public highway bridges: 2000
avg year built

Poor is an FHWA condition category from the lowest applicable component rating (4 or below), not a live crossing-safety or closure decision. Rankings cover counties with at least five public highway bridges.

Broomfield County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Broomfield County ranks #9 of 64 Colorado counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 1.5%). Broomfield County, Colorado contains 66 public highway bridges. Roughly 42.4% are rated “Good,” 56.1% “Fair,” and 1.5% “Poor.” Poor means the lowest applicable deck, superstructure, substructure, or culvert rating is 4 or below on the 0–9 NBI scale. It is a condition category, not a live safety or closure decision.

Responsible agencies inspect covered bridges on risk-based intervals under current NBIS rules and submit inventory data to FHWA annually. The list below shows every NBI-tracked bridge in the county. Use the “Sort by” controls to change the ordering, and click any row for its reported inspection date, traffic count, and condition fields.

Source: FHWA National Bridge Inventory. See methodology for full definitions.

Total bridges

Public highway bridges in Broomfield County

Good condition

42.4%

28 of 66 rated 7-9

Fair condition

56.1%

37 of 66 rated 5-6

Poor condition

1.5%

1 of 66 rated 4 or below

In-state Poor-share rank

#9 of 64

Among Colorado counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 66 NBI-tracked bridges by lowest applicable component rating.

Good

42.4% (28)

Fair

56.1% (37)

Poor

1.5% (1)

Broomfield County's Poor-condition bridges carry 25,000 vehicle crossings a day

That is 2.6% of the county's reported daily bridge traffic on 1.5% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 25,000 crossings a day against 17,076 for a Good-condition one. A Poor rating is a condition category, not a closure or a live safety judgement; it means the lowest applicable component rating is 4 or below.

Computed over the 66 of 66 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

4.5% of Broomfield County's bridges have passed the 50-year mark

3 of the 66 bridges with a recorded construction year were built in 1974 or earlier. Age alone is not a defect: a well-maintained older bridge can rate Good, and 42.4% of this county's inventory does. Even so, this older cohort is the population from which future Poor ratings are drawn, which is why the age profile below matters alongside the condition split above.

Cutoff derives from the 2024 release year minus a 50-year design life. Source: FHWA National Bridge Inventory, 2024 release.

One structure carries 100% of the county's Poor-condition bridge traffic

SH 121 ML SBND over US 287 ML RR SPUR, built 1972, carries 25,000 vehicles a day, the most of any Poor-rated structure here. The county's Poor-condition exposure is concentrated rather than evenly spread, so the 1-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 25,000 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1960s

1
1970s

2
1980s

5
1990s

13
2000s

39
2010s

6

What this shows Construction peaked in the 2000s, when 39 of the county's bridges still in the inventory were built, which is 59.1% of those with a recorded year. That cohort is now 15 to 24 years old in the 2024 inventory. Its average build year is 2000, 18 years newer than the Colorado average of 1982.

How Broomfield County compares with Colorado's closest counties by inventory size

The 5 Colorado counties nearest Broomfield County in number of bridges, with their condition splits. Its 1.5% Poor share is the 1st-lowest of these 6. Its average build year of 2000 against a peer-group mean of 1981 is 19 years newer.

Showing the 5 closest of 63 Colorado counties eligible for comparison.

Bridge inventory size and condition shares for Broomfield County and the 5 Colorado counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Bent County	68	23.5%	73.5%	2.9%	1976
Broomfield County (this page)	66	42.4%	56.1%	1.5%	2000
Delta County	64	51.6%	45.3%	3.1%	1986
Sedgwick County	64	40.6%	57.8%	1.6%	1981
Conejos County	62	38.7%	46.8%	14.5%	1976
Pitkin County	62	38.7%	58.1%	3.2%	1985

Each share is of that county's own total tracked bridges; peers are the counties with 5 or more bridges whose inventory size is closest to Broomfield County's. Source: FHWA National Bridge Inventory, 2024 release.

Nationwide counties with similar inventory size or average build year

Two NBI-derived peer sets for Broomfield County, both outside Colorado so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside CO (66 bridges here).

Chugach County, AK · 66 bridges
Inyo County, CA · 66 bridges
Cook County, GA · 66 bridges
Greene County, GA · 66 bridges

Similar average build year

Nearest mean year-built outside CO (2000 here).

Seminole County, FL · avg 2000 · 177 bridges
Dare County, NC · avg 2000 · 40 bridges
Aleutians East County, AK · avg 2000 · 16 bridges
Collin County, TX · avg 1998 · 1,127 bridges

Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.

All 66 Good 28 Fair 37 Poor 1

All bridges (66)

Sort:

Broomfield County Bridge Snapshot

Condition distribution

Broomfield County's Poor-condition bridges carry 25,000 vehicle crossings a day

4.5% of Broomfield County's bridges have passed the 50-year mark

One structure carries 100% of the county's Poor-condition bridge traffic

How Broomfield County compares with Colorado's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

All bridges (66)

US 287 ML

Hazel Street

104TH Street

96TH STREET

104TH AVE/CHURCH R

Briarwood Drive

Midway Blvd

West Sixth Avenue

NWP EB

NWP EB

NWP WB

NWP EB

NWP WB

NWP Ramp

120TH STREET

NWP Ramp

Sheridan Parkway

SH 128 (120TH AVE)

US 36 ML

SH 121 ML NBND

Chase Street

NWP EB

NWP WB

Huron Street

NWP EB

NWP WB

NWP EB

NWP WB

Lowell Blvd.

Main Street

East 1st Street

NWP Ramp

Interlocken Loop

Interlocken Blvd.

Interlocken Loop

Interlocken Loop

Northwest Parkway

Willow Run Pkwy

WB NWP Ramp

Ramp H

Willow Run Pkwy

Interlocken Loop N

Sheridan Boulevard

Zuni Street

NWP WB

US 36 ML

Lowell Blvd SB

Ramp B

SH 121 ML

Broadlands Drive

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