State profile · Near median Poor share

New Hampshire bridge safety

According to the Federal Highway Administration's 2024 National Bridge Inventory, condition ratings, load ratings, and Poor-condition shares for every public highway bridge in New Hampshire.

2,542
Public bridges
51.6%
Good condition
7.5%
Poor condition

New Hampshire holds 2,542 public highway bridges (#44 of 52 by inventory) with a 7.51% Poor share (#18 of 52 by Poor share).

That is 7.5% of the state's inventory, against an average of 7.5% across the 54 states and territories with Poor-rated bridges on file, which places it 35 of 54 ordered from the lowest Poor share upward. A bridge is rated Poor when its weakest applicable component scores 4 or below on the inspecting agency's 0-9 scale, so the category is a maintenance and funding signal rather than a closure order or a live crossing-safety verdict.

Inventory: FHWA NBI 2024 · last ETL August 2026

Total Bridges

2,542

Public highway bridges in New Hampshire

Good Condition

51.6%

1,312 bridges rated 7-9

1.6pp vs 50% benchmark

Poor Condition

7.5%

191 bridges whose lowest applicable component is rated 0-4

-0.0pp vs national avg 7.5%

New Hampshire vs national bridge condition

New Hampshire - Good condition share 51.6%
National avg

Share of bridges rated 7-9 on the FHWA 0-9 scale (deck, superstructure, substructure all good).

New Hampshire - Poor-condition share 25.0%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.5%.

New Hampshire in the national condition pattern

Each point is a state or territory in the FHWA NBI; the highlighted point is this profile.

Inventory size and Poor-condition share are different measures: New Hampshire has 2,542 bridges and a 7.5% Poor-condition share in the 2024 NBI, rank #35 of 54 jurisdictions ordered from the lowest share upward. The dashed comparisons mark the national average state rate and the midpoint of the plotted inventory range; neither is a live safety or closure threshold. Scatter plot of 54 data points. 0%10%20%30%40% 0k20k40k60k Public bridges in inventory (thousands) Poor-condition share (%) NH, Public bridges in inventory (thousands): 2.5k · Poor-condition share (%): 7.51%AL, Public bridges in inventory (thousands): 16.2k · Poor-condition share (%): 3.35%AK, Public bridges in inventory (thousands): 1.7k · Poor-condition share (%): 7.89%AZ, Public bridges in inventory (thousands): 8.6k · Poor-condition share (%): 1.15%AR, Public bridges in inventory (thousands): 13k · Poor-condition share (%): 5.43%CA, Public bridges in inventory (thousands): 25.8k · Poor-condition share (%): 5.91%CO, Public bridges in inventory (thousands): 9k · Poor-condition share (%): 4.82%CT, Public bridges in inventory (thousands): 4.4k · Poor-condition share (%): 4.72%DE, Public bridges in inventory (thousands): 0.9k · Poor-condition share (%): 1.26%DC, Public bridges in inventory (thousands): 0.3k · Poor-condition share (%): 1.95%FL, Public bridges in inventory (thousands): 13k · Poor-condition share (%): 2.79%GA, Public bridges in inventory (thousands): 15.1k · Poor-condition share (%): 1.59%GU, Public bridges in inventory (thousands): 0k · Poor-condition share (%): 12.77%HI, Public bridges in inventory (thousands): 1.2k · Poor-condition share (%): 6.53%ID, Public bridges in inventory (thousands): 4.6k · Poor-condition share (%): 4.9%IL, Public bridges in inventory (thousands): 26.9k · Poor-condition share (%): 9.35%IN, Public bridges in inventory (thousands): 19.5k · Poor-condition share (%): 5.22%IA, Public bridges in inventory (thousands): 23.7k · Poor-condition share (%): 19.16%KS, Public bridges in inventory (thousands): 24.9k · Poor-condition share (%): 5.26%KY, Public bridges in inventory (thousands): 14.5k · Poor-condition share (%): 7.37%LA, Public bridges in inventory (thousands): 12.7k · Poor-condition share (%): 11.48%ME, Public bridges in inventory (thousands): 2.5k · Poor-condition share (%): 15.41%MD, Public bridges in inventory (thousands): 5.5k · Poor-condition share (%): 4.56%MA, Public bridges in inventory (thousands): 5.3k · Poor-condition share (%): 8.88%MI, Public bridges in inventory (thousands): 11.4k · Poor-condition share (%): 11.27%MN, Public bridges in inventory (thousands): 13.5k · Poor-condition share (%): 4.44%MS, Public bridges in inventory (thousands): 16.7k · Poor-condition share (%): 6.03%MO, Public bridges in inventory (thousands): 24.6k · Poor-condition share (%): 8.95%MT, Public bridges in inventory (thousands): 5.2k · Poor-condition share (%): 6.81%NE, Public bridges in inventory (thousands): 15.4k · Poor-condition share (%): 7.9%NV, Public bridges in inventory (thousands): 2.1k · Poor-condition share (%): 1.14%NJ, Public bridges in inventory (thousands): 6.8k · Poor-condition share (%): 6.01%NM, Public bridges in inventory (thousands): 4k · Poor-condition share (%): 4.51%NY, Public bridges in inventory (thousands): 17.6k · Poor-condition share (%): 9.43%NC, Public bridges in inventory (thousands): 19.2k · Poor-condition share (%): 6.76%ND, Public bridges in inventory (thousands): 4.3k · Poor-condition share (%): 10.98%OH, Public bridges in inventory (thousands): 26.7k · Poor-condition share (%): 4.74%OK, Public bridges in inventory (thousands): 22.9k · Poor-condition share (%): 7.7%OR, Public bridges in inventory (thousands): 8.3k · Poor-condition share (%): 4.61%PA, Public bridges in inventory (thousands): 23.3k · Poor-condition share (%): 12.58%PR, Public bridges in inventory (thousands): 2.4k · Poor-condition share (%): 13.92%RI, Public bridges in inventory (thousands): 0.8k · Poor-condition share (%): 15.2%SC, Public bridges in inventory (thousands): 9.5k · Poor-condition share (%): 6.17%SD, Public bridges in inventory (thousands): 5.9k · Poor-condition share (%): 16.36%TN, Public bridges in inventory (thousands): 20.4k · Poor-condition share (%): 4.41%TX, Public bridges in inventory (thousands): 56.7k · Poor-condition share (%): 1.23%UT, Public bridges in inventory (thousands): 3.1k · Poor-condition share (%): 2.91%VT, Public bridges in inventory (thousands): 2.9k · Poor-condition share (%): 2.9%VI, Public bridges in inventory (thousands): 0k · Poor-condition share (%): 29.17%VA, Public bridges in inventory (thousands): 14.1k · Poor-condition share (%): 3.39%WA, Public bridges in inventory (thousands): 8.5k · Poor-condition share (%): 5.45%WV, Public bridges in inventory (thousands): 7.3k · Poor-condition share (%): 18.64%WI, Public bridges in inventory (thousands): 14.4k · Poor-condition share (%): 6.52%WY, Public bridges in inventory (thousands): 3.1k · Poor-condition share (%): 6.51%
Inventory size and Poor-condition share are different measures: New Hampshire has 2,542 bridges and a 7.5% Poor-condition share in the 2024 NBI, rank #35 of 54 jurisdictions ordered from the lowest share upward. The dashed comparisons mark the national average state rate and the midpoint of the plotted inventory range; neither is a live safety or closure threshold.

New Hampshire vs all states by public bridge inventory

Where this state's FHWA NBI public-highway bridge count sits among every state and territory on PlainBridges

2,542 44th of 54 higher than 10 of 54 states

States and territories, banded by public bridge inventory size

Each bar is a band; taller bars hold more states. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source FHWA National Bridge Inventory · 2024

Read the rank neighborhood for New Hampshire

The highlighted point is New Hampshire: 2,542 bridges and 7.51% in Poor condition, rank #35 of 54 jurisdictions ordered from the lowest share upward. The five jurisdictions immediately above and below New Hampshire on that same Poor-share ordering:

  • Montana: 5,224 bridges · 6.81% Poor
  • Kentucky: 14,548 bridges · 7.37% Poor
  • New Hampshire: 2,542 bridges · 7.51% Poor
  • Oklahoma: 22,917 bridges · 7.70% Poor
  • Alaska: 1,685 bridges · 7.89% Poor

The full national sortable table lives on the rankings page.

Material families in New Hampshire

Exclusive FHWA material families across all 2,542 bridges in this state; continuous variants fold into the parent family. Orthogonal to the Poor-share scatter above.

Who maintains New Hampshire’s inventory

State agency holds 58.0% of the 2,542 public highway bridges filed under New Hampshire in the 2024 NBI, the agency-of-record split for this state, not a condition verdict.

When New Hampshire’s bridges were built

Pre-1950 construction accounts for 26.2% of the 2,542 bridges with a recorded original year in New Hampshire. Era bands are orthogonal to the Poor-share ranking above.

Condition Distribution

New Hampshire51.6%40.9%GoodFairPoor
Bridge inventory deck-condition mix - New Hampshire (FHWA NBI)

Counties (10)

Belknap 112 Carroll 193 Cheshire 192 Coos 188 Grafton 544 Hillsborough 385 Merrimack 326 Rockingham 308 Strafford 136 Sullivan 158

New Hampshire vs nearby ranks

Adjacent states by Poor-condition share (lower share = better)

States are ranked by the share of bridges whose lowest applicable component rating is 4 or below. This describes recorded condition; it does not measure funding effectiveness or live crossing safety. States here sit immediately above and below New Hampshire on the same metric.

MT

Montana

6.81% top marginal rate
Structure
Progressive
Burden @ $100K
$5,224

KY

Kentucky

7.37% top marginal rate
Structure
Progressive
Burden @ $100K
$14,548
Selected

NH

New Hampshire

7.51% top marginal rate
Structure
Progressive
Burden @ $100K
$2,542

OK

Oklahoma

7.70% top marginal rate
Structure
Progressive
Burden @ $100K
$22,917

AK

Alaska

7.89% top marginal rate
Structure
Progressive
Burden @ $100K
$1,685

Bridges Needing Most Attention in New Hampshire

Six lowest-condition bridges in New Hampshire, ranked by the portal's composite display score. Inspection intervals are risk-based under current NBIS rules.

THORNTONS FERRY RD

Poor

Over: BEAVER BROOK

3.2 MI FR MERRIMACK TL, Hillsborough, NH

Built 1970 Load: 0.0 t ADT: 388

GRIST MILL HILL RD

Poor

Over: INDIAN RIVER

2.01 MI FROM GRAFTON TL, Grafton, NH

Built 1956 Load: 0.0 t ADT: 404

GRANITE ROAD

Poor

Over: SOUTH RIVER

0.3MI. RTE 153, Carroll, NH

Built 1920 Load: 0.0 t ADT: 90

OLD COUNTY RD N

Poor

Over: COLLINS BROOK

2.4 MI. DEERING TL, Hillsborough, NH

Built 1981 Load: 0.0 t ADT: 90

SOUTH ROAD

Poor

Over: MINNEWAWA BROOK

0.9 MI FR DUBLIN TL, Cheshire, NH

Built 1950 Load: 0.0 t ADT: 90

STEARNS BROOK ROAD

Poor

Over: STEARNS BROOK

0.4 MI FR SUCCESS TL, Coos, NH

Built 1950 Load: 0.0 t ADT: 90

All Bridges in New Hampshire

GOVNRS ISLAND RD

Fair

Over: LAKE WINNIPESAUKEE

AT LACONIA/GILFORD TL, Belknap, NH

Built 1981 Load: 28.1 t ADT: 1,682

US 4

Fair

Over: OYSTER RIVER

.2 MI FROM JCT RT 25, Strafford, NH

Built 1929 Load: 28.1 t ADT: 18,235

DORCHESTER ROAD

Fair

Over: GRANT BROOK

1.0 MI JCT ROUTE 10, Grafton, NH

Built 1940 Load: 28.1 t ADT: 1,110

US 3 NH116 NH142

Fair

Over: JOHNS RIVER

2.3 MI FROM CARROLL TL, Coos, NH

Built 1938 Load: 28.1 t ADT: 9,574

I-93 NB

Fair

Over: AMMONOOSUC RIVER

2 MI BETHLEHEM TL, Grafton, NH

Built 1960 Load: 28.2 t ADT: 4,172

PURLING BECK ROAD

Fair

Over: BEARDS BROOK

0.04 MI FR EAST WASH. RD, Sullivan, NH

Built 1920 Load: 28.2 t ADT: 90

FDR 233

Fair

Over: BOG BROOK

MAP 23, Carroll, NH

Built 1977 Load: 28.2 t ADT: 99

FRENCH POND ROAD

Fair

Over: CLARK BROOK

0.18 MI FR BLACKMOUNT RD, Grafton, NH

Built 1983 Load: 28.4 t ADT: 709

SUBMARINE WAY

Fair

Over: NORTH MILL POND

0.1 FROM SARAH LONG BR., Rockingham, NH

Built 1984 Load: 28.4 t ADT: 10

NFSR 700

Fair

Over: TUNNEL BROOK

NO DATA ENTERED, Grafton, NH

Built 1972 Load: 28.5 t ADT: 50

I-89 SB

Fair

Over: WARNER RIVER

6.2MI HOPKINTON T.L., Merrimack, NH

Built 1966 Load: 28.6 t ADT: 13,139

GALE CHANDLER ROAD

Fair

Over: MILL BROOK

100 FT FR BROOK RD, Grafton, NH

Built 1922 Load: 28.8 t ADT: 116

MAIN STREET

Fair

Over: SUNCOOK RIVER

1.3 MI N CHICHESTER TL, Merrimack, NH

Built 1942 Load: 28.8 t ADT: 4,344

NH 25 NH118

Fair

Over: S BRANCH BAKER RIVER

0.1 MI W OF RUMNEY TL, Grafton, NH

Built 1978 Load: 28.8 t ADT: 3,915

NH 12

Fair

Over: MILL BROOK

1.73 MI FROM SURRY TL, Cheshire, NH

Built 1941 Load: 28.8 t ADT: 6,382

BURTON HIGHWAY

Fair

Over: BURTON POND OUTLET

TOWN RD, Hillsborough, NH

Built 1920 Load: 28.8 t ADT: 90

FDR 31

Fair

Over: EASTMAN BROOK

MAP 38, Grafton, NH

Built 1982 Load: 28.8 t ADT: 50

GOULD HILL ROAD

Fair

Over: BOG POND OUTLET

1.5 MI FR MASCOMA RD, Merrimack, NH

Built 1950 Load: 28.9 t ADT: 90

STOWELL ROAD

Fair

Over: BABOOSIC BROOK

338 FT FR BEDFORD TL, Hillsborough, NH

Built 1990 Load: 28.9 t ADT: 481

HARRIS ROAD

Fair

Over: SALMON BROOK

.1 MI W OF E DUNSTABLE RD, Hillsborough, NH

Built 1955 Load: 28.9 t ADT: 13,995

US 3

Fair

Over: MOHAWK RIVER

1.3 MI NE COLUMBIA TL, Coos, NH

Built 1934 Load: 29.0 t ADT: 2,906

BROOK ROAD

Fair

Over: GUNNISON BROOK

.47 MI N E OF JCT NH 10, Sullivan, NH

Built 1945 Load: 29.0 t ADT: 991

I-89 NH 10 NB

Fair

Over: TRUCK ROAD MASCOMA RIVER

5.9 MI ENFIELD T.L., Grafton, NH

Built 1966 Load: 29.0 t ADT: 22,632

CAUSEWAY ROAD

Fair

Over: MILL CREEK

0.03 MI FROM DEPOT ROAD, Rockingham, NH

Built 1940 Load: 29.0 t ADT: 625

NH116 NH142

Fair

Over: BOG BROOK

0.1 MI FROM JCT ROUTE 3, Coos, NH

Built 1956 Load: 29.0 t ADT: 4,656

SMITH RIVER ROAD

Fair

Over: SMITH RIVER

0.7 MI FROM DANBURY T.L., Grafton, NH

Built 1937 Load: 29.2 t ADT: 154

NH 27

Fair

Over: I-95

.5 MI N. HAMPTON T.L., Rockingham, NH

Built 1976 Load: 29.2 t ADT: 10,018

I-93 SB

Fair

Over: INDUSTRIAL PK NHRR(ABD)

2 MI BETHLEHEM TL, Grafton, NH

Built 1959 Load: 29.2 t ADT: 4,433

I-93 NB

Fair

Over: INDUSTRIAL PK NHRR(ABD)

2 MI BETHLEHEM TL, Grafton, NH

Built 1959 Load: 29.2 t ADT: 4,172

I-93 SB NH101 WB

Fair

Over: HANOVER STREET

1.8MI W JCT RTE 28 A, Hillsborough, NH

Built 1960 Load: 29.2 t ADT: 46,422

NH103

Fair

Over: ANDREW BROOK

3.8 MI FROM BRADFORD TL, Merrimack, NH

Built 1937 Load: 29.2 t ADT: 4,766

RYE HARBOR ROAD

Fair

Over: BROOK

0.3 MI FROM RTE 1A, Rockingham, NH

Built 1970 Load: 29.2 t ADT: 561

I-89 SB

Fair

Over: NORTH HOMINY POT RD

0.6MI FROM NEW LONDON TL., Merrimack, NH

Built 1967 Load: 29.2 t ADT: 9,249

I-89 NB

Fair

Over: NORTH HOMINY POT RD

0.5MI FROM NEW LONDON TL, Merrimack, NH

Built 1967 Load: 29.2 t ADT: 9,260

NH 16

Fair

Over: BRANCH RIVER

0.7 MI FROM MILTON T.L., Carroll, NH

Built 1966 Load: 29.2 t ADT: 12,702

BIXBY LANE

Fair

Over: BAKER RIVER

0.02MI NH25, Grafton, NH

Built 1976 Load: 29.2 t ADT: 25

NO DATA ENTERED

Fair

Over: EASTSIDE TRIB 3

NO DATA ENTERED, Grafton, NH

Built 2015 Load: 29.2 t ADT: 10

NH175

Fair

Over: BEEBE RIVER

3.5 MI N JCT RTE 3, Grafton, NH

Built 1934 Load: 29.4 t ADT: 935

SECOND NH TPK

Fair

Over: S BR PISCATAQUOG RIVER

0.44MI. LYNDEBORO TL, Hillsborough, NH

Built 1962 Load: 29.4 t ADT: 1,214

NH 13

Fair

Over: WHITTLE BROOK

1.6 MI NE NEW BOSTON TL, Hillsborough, NH

Built 1932 Load: 29.4 t ADT: 4,460

SIMONDSVILLE ROAD

Fair

Over: ASHUELOT RIVER

0.3 MI. RTE. 10, Cheshire, NH

Built 1969 Load: 29.4 t ADT: 100

I-89 NB

Fair

Over: BOG ROAD

1.4 MI FROM SUTTON TL, Merrimack, NH

Built 1967 Load: 29.4 t ADT: 9,607

NH 12

Fair

Over: MILL BROOK

2.5 MI TO WALPOLE TL, Cheshire, NH

Built 1948 Load: 29.4 t ADT: 6,382

WATERWORKS DRIVE

Fair

Over: CANAL OUTLET

NEAR JCT CANAL/COHAS AVES, Hillsborough, NH

Built 1940 Load: 29.6 t ADT: 25

I-95 SB CONNECTOR

Fair

Over: I-95 NB

SP TPK I-95 INTERCHANGE, Rockingham, NH

Built 1972 Load: 29.6 t ADT: 5,150

I-89 NB

Fair

Over: WARNER RIVER

4.1 MI HOPKINTON T.L., Merrimack, NH

Built 1966 Load: 29.6 t ADT: 10,670

I-93 NB

Fair

Over: NH132

SANBORNTON T.L., Belknap, NH

Built 1963 Load: 29.7 t ADT: 14,051

NH 26

Fair

Over: CONNECTICUT RIVER

VERMONT STATE LINE, Coos, NH

Built 1953 Load: 29.8 t ADT: 907

NH114

Fair

Over: US202 NH 9

3.05 MI FROM WARNER T.L., Merrimack, NH

Built 1974 Load: 29.8 t ADT: 5,411

NH112

Fair

Over: HANCOCK BROOK

3.1 MI E OF LIVERMORE TL, Grafton, NH

Built 1942 Load: 29.8 t ADT: 3,061

Showing 401-450 of 2,542 bridges

Related

All states → | National rankings → | Understanding conditions → | Retired SD term explained →
Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges.

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from the FHWA National Bridge Inventory (NBI). Poor condition is an inspection-record category, not a closure or unsafe-to-cross designation. Consult the bridge owner for current status.

Understanding Bridge Conditions

How FHWA rates bridge condition on a 0-9 scale.

Check Your Daily Bridges

How to look up bridge condition data for bridges on your route.

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

What to do with this

Use New Hampshire's inventory picture to drill to a county or a specific span.

  • Browse counties in New Hampshire and open the highest-Poor shares first. County list
  • See where this state sits among peers on Poor-condition share. State rankings
  • Compare this state with another jurisdiction on the same measures. State compare

NBI condition ratings are inventory snapshots, not live crossing-safety verdicts.

Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. New Hampshire Good/Fair/Poor shares and county rollups on this page are computed from the same NBI extract as the national boards; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2024 NBI release. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.