County profile · official public datasets

Coos County, NH

188 public highway bridges tracked in the FHWA National Bridge Inventory: 49.5% rated Good, 44.1% Fair, 6.4% Poor.

188
Public bridges
49.5%
Good condition
6.4%
Poor condition

The verdict

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

Coos County posts a better-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.

Top 40%
lowest Poor share in state
6.4%
Poor-condition share
188
public highway bridges
1964
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.

Coos County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Coos County ranks #4 of 10 New Hampshire counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 6.4%). Coos County, New Hampshire contains 188 public highway bridges. Roughly 49.5% are rated “Good,” 44.1% “Fair,” and 6.4% “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

188

Public highway bridges in Coos County

Good condition

49.5%

93 of 188 rated 7-9

Fair condition

44.1%

83 of 188 rated 5-6

Poor condition

6.4%

12 of 188 rated 4 or below

In-state Poor-share rank

#4 of 10

Among New Hampshire counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 188 NBI-tracked bridges by lowest applicable component rating.

Good
49.5% (93)
Fair
44.1% (83)
Poor
6.4% (12)

Coos County's Poor-condition bridges carry 5,976 vehicle crossings a day

That is 2.1% of the county's reported daily bridge traffic on 6.5% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 498 crossings a day against 1,515 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 185 of 188 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

63.8% of Coos County's bridges have passed the 50-year mark

120 of the 188 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 49.5% 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 71.8% of the county's Poor-condition bridge traffic

US 2 over PEA BROOK, built 1932, carries 4,291 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 12-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 5,976 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

When Coos County's bridges were built

188 bridges with a recorded construction year, grouped by decade

bridges

What this shows Construction peaked in the 1960s, when 27 of the county's bridges still in the inventory were built, which is 14.4% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year (1964) matches the New Hampshire average (1968).

Source FHWA National Bridge Inventory (year built) As of 2024 NBI release

How Coos County compares with New Hampshire's closest counties by inventory size

The 5 New Hampshire counties nearest Coos County in number of bridges, with their condition splits. Its 6.4% Poor share is the 4th-lowest of these 6. Its average build year of 1964 against a peer-group mean of 1966 is in line with the group.

Showing the 5 closest of 9 New Hampshire counties eligible for comparison.

Bridge inventory size and condition shares for Coos County and the 5 New Hampshire counties closest to it in inventory size
County Bridges Poor
Carroll County 193 4.1%
Cheshire County 192 11.5%
Coos County (this page) 188 6.4%
Sullivan County 158 5.1%
Strafford County 136 8.8%
Belknap County 112 4.5%

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 Coos 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 Coos County, both outside New Hampshire so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside NH (188 bridges here).

Similar average build year

Nearest mean year-built outside NH (1964 here).

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

All 188 Good 93 Fair 83 Poor 12

Good-condition bridges (93)

FDR 71

Good

Over: CULHANE BROOK

MAP 13, Coos, NH

Built 1960 Load: 18.5 t ADT: 50

NH 26

Good

Over: CORSER BROOK

3.0 MI W OF RTE 16, Coos, NH

Built 1954 Load: 19.1 t ADT: 971

NORTHSIDE ROAD

Good

Over: UPPER AMMONOOSUC RIVER

234 FT FROM NH110, Coos, NH

Built 1862 Load: 21.2 t ADT: 375

BRIDGE STREET

Good

Over: CONNECTICUT RIVER

VERMONT STATE LINE, Coos, NH

Built 1930 Load: 23.7 t ADT: 544

FDR 11

Good

Over: E.BR. MILL BROOK

MAP 01, Coos, NH

Built 1982 Load: 23.7 t ADT: 50

PLEASANT VALLEY RD

Good

Over: GREAT BROOK

0.7 MI FR GARLAND RD, Coos, NH

Built 1956 Load: 24.5 t ADT: 90

MERIDEN HILL ROAD

Good

Over: LYMAN BROOK

1.3 MI FROM US RTE 3, Coos, NH

Built 1960 Load: 25.3 t ADT: 134

US 3

Good

Over: SIMMS STREAM

0.5 MI SW COLEBROOK TL, Coos, NH

Built 1956 Load: 25.9 t ADT: 3,419

EAST MILAN ROAD

Good

Over: STEARNS BROOK

1.4MI FROM BERLIN TL, Coos, NH

Built 1982 Load: 27.1 t ADT: 999

US 2

Good

Over: RECREATIONAL TRAIL

1.4 MI RANDOLPH TL, Coos, NH

Built 1960 Load: 29.9 t ADT: 5,144

US302

Good

Over: AMMONOOSUC RIVER

2.7 MI E. INT. US 3, Coos, NH

Built 1974 Load: 31.0 t ADT: 4,613

FARAWAY ROAD

Good

Over: JOHNS RIVER

131 FT FR SMITH FOREST R, Coos, NH

Built 1976 Load: 31.8 t ADT: 90

NORTH ROAD

Good

Over: OTTER BROOK

2.9 MI NW JEFFERSON TL, Coos, NH

Built 1958 Load: 32.2 t ADT: 1,214

BUNGY ROAD

Good

Over: MOHAWK RIVER

0.01 MI S JCT NH 26, Coos, NH

Built 1977 Load: 32.7 t ADT: 308

NH115

Good

Over: CHERRY MILL BROOK

2.9 MI SW JCT US RT 2, Coos, NH

Built 1984 Load: 32.7 t ADT: 3,637

US 2

Good

Over: CLEMENT BROOK

5.1 MI FROM GORHAM TL, Coos, NH

Built 1967 Load: 32.7 t ADT: 3,495

US 2

Good

Over: CONNOR BROOK

0.2 MI FROM MAINE SL, Coos, NH

Built 1960 Load: 32.7 t ADT: 3,495

NH115A

Good

Over: CHERRY MILL BROOK

3.1 MI CARROLL TL, Coos, NH

Built 1950 Load: 33.7 t ADT: 514

JEFFERSON NOTCH RD

Good

Over: S BRANCH BAKER RIVER

1.0 MI S JEFFERSON TL, Coos, NH

Built 1939 Load: 34.3 t ADT: 90

NH 26

Good

Over: WEST BRANCH CLEAR STREAM

0.6 MI FROM DIXVILLE TL, Coos, NH

Built 1953 Load: 35.6 t ADT: 971

NH110

Good

Over: JERICHO BROOK

3.3 MI JCT NH 110 & NH 16, Coos, NH

Built 1954 Load: 36.2 t ADT: 1,878

US302

Good

Over: DECEPTION BROOK

3.6 MI E. JCT US3, Coos, NH

Built 1974 Load: 36.3 t ADT: 3,804

DOLLY COPP ROAD

Good

Over: PEABODY RIVER

.46 MI. S. GORHAM T.L., Coos, NH

Built 1950 Load: 36.3 t ADT: 437

NH115A

Good

Over: PRISCILLA BROOK

1.8 MI S JCT US 2, Coos, NH

Built 1967 Load: 36.7 t ADT: 819

EAST SIDE RIVER RD

Good

Over: CHICKWOLNEPY STREAM

1.7 MI S DUMMER TL, Coos, NH

Built 1950 Load: 37.1 t ADT: 261

US 2

Good

Over: PEABODY RIVER

4.8 MI FROM RANDOLPH TL, Coos, NH

Built 1982 Load: 37.2 t ADT: 4,291

INGERSON ROAD

Good

Over: PRISCILLA BROOK

1 MI FROM US 2 WEST END, Coos, NH

Built 2015 Load: 38.8 t ADT: 90

NORTH ROAD

Good

Over: GARLAND BROOK

0.54 MI W JEFFERSON TL, Coos, NH

Built 1960 Load: 39.0 t ADT: 505

NH116

Good

Over: ISRAEL RIVER

1.2 MI SW JCT US 2, Coos, NH

Built 1987 Load: 39.4 t ADT: 1,029

CASCADE FLATS

Good

Over: TINKER BROOK

2 10th m. fr NH16 S. END, Coos, NH

Built 2018 Load: 39.6 t ADT: 480

JOSIE ROAD

Good

Over: MOHAWK RIVER

2.8 MI FROM DIXVILLE TL, Coos, NH

Built 1986 Load: 40.8 t ADT: 90

US 2 NH 16

Good

Over: MOOSE RIVER

5.1 MI FROM MARTINS LOC., Coos, NH

Built 1939 Load: 40.8 t ADT: 10,303

US 3

Good

Over: UPPER AMMONOOSUC RIVER

4.4 MI FROM LANCASTER TL, Coos, NH

Built 1995 Load: 40.8 t ADT: 5,358

BELL HILL ROAD

Good

Over: UPPER AMMONOOSUC RIVER

.06 MI FROM NH110, Coos, NH

Built 1990 Load: 40.8 t ADT: 90

DEWEY HILL ROAD

Good

Over: PHILLIPS BROOK

0.5 MI FR DUMMER TL, Coos, NH

Built 1996 Load: 40.8 t ADT: 43

JEFFERSON NOTCH RD

Good

Over: AMMONOOSUC RIVER

.4MIJCT 42 + 44, Coos, NH

Built 1982 Load: 41.2 t ADT: 90

CAMPGROUND ROAD

Good

Over: MOOSE BROOK

.25 MI S JIM TOWN ROAD, Coos, NH

Built 1964 Load: 41.2 t

US 3

Good

Over: KIMBALL BROOK

8.5 MI TO NORTHUMBERLAND, Coos, NH

Built 1956 Load: 41.2 t ADT: 2,621

MERIDEN HILL ROAD

Good

Over: LYMAN BROOK

0.7 MI FROM US RTE 3, Coos, NH

Built 2014 Load: 41.3 t ADT: 134

BRIDGE HILL ROAD

Good

Over: CONNECTICUT RIVER

NH-VT STATE LINE, Coos, NH

Built 1997 Load: 41.3 t ADT: 857

WASHBURN ROAD

Good

Over: MOHAWK RIVER

110 FT FROM NH RTE 26, Coos, NH

Built 1920 Load: 41.5 t ADT: 90

EMERSON ROAD

Good

Over: UPPER AMMONOOSUC RIVER

1.04 MI FR NORTHUMBERLAN, Coos, NH

Built 1982 Load: 41.7 t ADT: 90

PARIS ROAD

Good

Over: UPPER AMMONOOSUC RIVER

217 FT FR NH110, Coos, NH

Built 2000 Load: 41.7 t ADT: 148

US 3

Good

Over: BISHOP BROOK

0.1 MI CLARKSVILLE TL, Coos, NH

Built 1924 Load: 42.2 t ADT: 1,802

NH 16

Good

Over: CLEAR STREAM

0.1 MI SW OF RTE 26, Coos, NH

Built 1997 Load: 42.3 t ADT: 842

PATROL SHED ROAD

Good

Over: STONY BROOK

2.01 MI N JACKSON TL, Coos, NH

Built 2011 Load: 42.6 t

US 2

Good

Over: RATTLE RIVER

2.9 MI EAST OF GORHAM T/L, Coos, NH

Built 1973 Load: 43.6 t ADT: 3,361

NH115

Good

Over: ISRAEL RIVER

1.2 MI SW JCT US RTE 2, Coos, NH

Built 1984 Load: 44.1 t ADT: 3,637

HAZEN ROAD

Good

Over: JOHNS RIVER

2.3 MI FR JEFFERSON TL, Coos, NH

Built 2020 Load: 44.1 t ADT: 90

VALLEY ROAD

Good

Over: ISRAEL RIVER

0.66 MI WEST OF JCT US 2, Coos, NH

Built 1986 Load: 44.3 t ADT: 142

Read our methodology - how this data is sourced, computed, and verified.

Related

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Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainBridges

Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.