State profile · Near national median SD

New Hampshire bridge safety

Condition ratings, load ratings, and structural-deficiency data for every public highway bridge in New Hampshire — drawn straight from the FHWA National Bridge Inventory.

2,542
Public bridges
43.0%
Good condition
7.1%
Poor condition
7.1%
Structurally deficient

Total Bridges

2,542

Public highway bridges in New Hampshire

Good Condition

43.0%

1,092 bridges rated 7-9

-7.0pp vs 50% benchmark

Poor Condition

7.1%

180 bridges rated 0-4

Structurally Deficient

7.1%

180 bridges flagged for repair priority

0.1pp vs national avg 7.0%

New Hampshire vs national bridge condition

New Hampshire — Good condition share 43.0%
National avg

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

New Hampshire — Structurally deficient share 23.6%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.

Condition Distribution

Bridge inventory deck-condition mix — New Hampshire (FHWA NBI)

New Hampshire42.95830055074744%35.641227380015735%GoodFairPoorStructurally Deficient
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 on the structurally deficient leaderboard (lower share = better)

States are ranked by share of bridges flagged structurally deficient — the FHWA classification for any span where deck, superstructure, or substructure carries a condition rating of 4 or below. Lower percentages indicate stronger maintenance funding and inspection follow-through. States here sit immediately above and below New Hampshire on the same metric.

36

New York

6.90% top marginal rate
Structure
Progressive
Burden @ $100K
$19,132

21

Kentucky

7.06% top marginal rate
Structure
Progressive
Burden @ $100K
$14,554
Selected

33

New Hampshire

7.08% top marginal rate
Structure
Progressive
Burden @ $100K
$2,542

40

Oklahoma

7.50% top marginal rate
Structure
Progressive
Burden @ $100K
$22,733

35

New Mexico

7.61% top marginal rate
Structure
Progressive
Burden @ $100K
$368

Bridges Needing Most Attention in New Hampshire

Six lowest-condition bridges in New Hampshire, ranked by composite NBI rating. Each is inspected at least every 24 months.

OLD DEERFIELD ROAD

Poor

Over: BROOK

185 FT FROM NH RTE 43, Rockingham, NH

Built 1920 Load: 1.8 t ADT: 190

TEMPLETON TURNPIKE

Structurally Deficient

Over: PRIEST BROOK

1.9MI. RTE 119, Cheshire, NH

Built 1984 Load: 2.7 t ADT: 86

DUDLEY ROAD

Structurally Deficient

Over: LAMPREY RIVER

.23 MI JCT 101, Rockingham, NH

Built 1914 Load: 2.9 t ADT: 535

SHOP ROAD

Structurally Deficient

Over: NEEDLE SHOP BROOK

0.8 MI N NEW CHESTER RD, Merrimack, NH

Built 1930 Load: 3.3 t ADT: 63

WHITCOMB MILLS RD

Poor

Over: WHITE BROOK

0.06 MI FR ARCH ST, Cheshire, NH

Built 1940 Load: 3.6 t ADT: 814

LEIGHTON MEADOW RD

Structurally Deficient

Over: PHILLIPS BROOK

100 FT FR SULLIVAN RD 61, Coos, NH

Built 1940 Load: 3.6 t ADT: 90

All Bridges in New Hampshire

I-93 NB

Good

Over: NH141

4.2 MI SUGARHILL TL, Grafton, NH

Built 1972 Load: 34.7 t ADT: 2,401

US302,NH 16

Good

Over: EAST BRANCH SACO RIVER

1.7 MI CONWAY TL, Carroll, NH

Built 1961 Load: 34.8 t ADT: 11,844

I-93 NB

Good

Over: NH135

1.4MI VT LINE, Grafton, NH

Built 1982 Load: 34.9 t ADT: 3,307

I-93 SB

Good

Over: NH135

1.4MI. VT LINE, Grafton, NH

Built 1982 Load: 34.9 t ADT: 3,262

MAIN STREET

Good

Over: MASCOMA LAKE

.13 MI. FROM JCT RTE 4-A, Grafton, NH

Built 2012 Load: 35.1 t ADT: 1,331

NH 32

Good

Over: MARTIN BROOK

2.38MI N RICHMOND TL, Cheshire, NH

Built 1929 Load: 35.3 t ADT: 2,912

SHINDAGEN ROAD

Good

Over: BROOK

.05 MI FROM VILLAGE ROAD, Merrimack, NH

Built 1940 Load: 35.3 t ADT: 143

I-93 SB

Good

Over: BLAIR ROAD

2.1 MI FROM PLYMOUTH TL, Grafton, NH

Built 1967 Load: 35.4 t ADT: 10,181

NH 10

Good

Over: CLARK BROOK

4.6 MI N. PIERMONT T.L., Grafton, NH

Built 1940 Load: 35.4 t ADT: 3,661

I-93 NB

Good

Over: NH 18

6.7 MI FROM VT SL, Grafton, NH

Built 1986 Load: 35.4 t ADT: 3,652

I-93 SB

Good

Over: NH 18

6.6 MI FROM VT SL, Grafton, NH

Built 1986 Load: 35.4 t ADT: 3,868

CONNORS MILL ROAD

Good

Over: SCHOODAC BROOK

0.9 MI FROM WEBSTER TL, Merrimack, NH

Built 2009 Load: 35.4 t ADT: 90

US302, NH 10

Good

Over: AMMONOOSUC RIVER

2.9 MI FROM CARROLL TL, Grafton, NH

Built 1983 Load: 35.5 t ADT: 3,217

NH 26

Good

Over: WEST BRANCH CLEAR STREAM

0.6 MI FROM DIXVILLE TL, Coos, NH

Built 1953 Load: 35.6 t ADT: 971

TEAGUE DRIVE

Good

Over: SPICKET RIVER

100' SOUTH PARKER CIR., Rockingham, NH

Built 2014 Load: 35.6 t ADT: 446

NH 25,NH118

Good

Over: BAKER RIVER

5.8 MI FROM BENTON TL, Grafton, NH

Built 1962 Load: 35.7 t ADT: 3,654

NORTHWOOD ROAD

Good

Over: BUZZEL'S RUN BROOK

TOWN RD 1.1MI NORWD TL, Strafford, NH

Built 2010 Load: 35.7 t ADT: 652

US 302

Good

Over: BEMIS BROOK

5.8 MI CARROLL TL, Carroll, NH

Built 1950 Load: 35.9 t ADT: 2,100

WASHBURN ROAD

Good

Over: PATTEN BROOK

2.3 MI FROM BRISTOL TL, Grafton, NH

Built 1952 Load: 35.9 t ADT: 702

I-93 SB

Good

Over: BOG BROOK

1.1 MI FROM PLYMOUTH T.L., Grafton, NH

Built 1968 Load: 35.9 t ADT: 10,181

NH128

Good

Over: BEAVER BROOK

WINDHAM TL, Hillsborough, NH

Built 1935 Load: 35.9 t ADT: 4,716

US 3,NH 25

Good

Over: OWL BROOK

0.8 MI ASHLAND-HOLDERNESS, Grafton, NH

Built 1958 Load: 36.1 t ADT: 6,267

SANDOWN ROAD

Good

Over: EXETER RIVER

.1 MI EAST SANDOWN TL, Rockingham, NH

Built 2010 Load: 36.1 t ADT: 187

NH110

Good

Over: JERICHO BROOK

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

Built 1954 Load: 36.2 t ADT: 1,878

STILLWATER CIRCLE

Good

Over: BROOK

600FT S JCT FLAGG RD, Strafford, NH

Built 1988 Load: 36.2 t ADT: 780

VALLEY ROAD

Good

Over: DAN HOLE RIVER

0.11 MI FR MOULTONVILLE, Carroll, NH

Built 2018 Load: 36.3 t ADT: 90

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

TRICNIT ROAD

Good

Over: FURNACE BROOK

0.1 MI FR NH RTE 124, Hillsborough, NH

Built 2009 Load: 36.3 t ADT: 453

BOROUGH ROAD

Good

Over: SMITH RIVER

AT BRISTOL T/L, Merrimack, NH

Built 2010 Load: 36.3 t ADT: 90

NH152

Good

Over: NORTH RIVER

0.1 MI NOTTINGHAM TL, Strafford, NH

Built 1928 Load: 36.3 t ADT: 2,873

NH101

Good

Over: BLOOD BROOK

1.6 MI FROM WILTON TL, Hillsborough, NH

Built 1930 Load: 36.6 t ADT: 7,557

NH111

Good

Over: CSX

3.04MI NW JCT 1-A, Rockingham, NH

Built 1927 Load: 36.6 t ADT: 4,335

US 4,NH 16,TPK SB

Good

Over: LITTLE BAY,RD

DOVER-NEWINGTON T.L., Strafford, NH

Built 2018 Load: 36.6 t ADT: 33,175

NH 63

Good

Over: PARTRIDGE BROOK

2.0 MI FM CHESTERFIELD TL, Cheshire, NH

Built 1969 Load: 36.7 t ADT: 1,594

NH115A

Good

Over: PRISCILLA BROOK

1.8 MI S JCT US 2, Coos, NH

Built 1967 Load: 36.7 t ADT: 819

OAK HILL ROAD

Good

Over: GRAFTON POND OUTLET

AT GRAFTON RD INTER., Grafton, NH

Built 2023 Load: 36.9 t ADT: 90

MILL STREET

Good

Over: LAMPREY RIVER

TOWN RD, Rockingham, NH

Built 2004 Load: 36.9 t ADT: 1,112

GARDEN ROAD

Good

Over: LITTLE RIVER

0.5 MI. RTE.125, Rockingham, NH

Built 2010 Load: 36.9 t ADT: 1,856

EAST SIDE RIVER RD

Good

Over: CHICKWOLNEPY STREAM

1.7 MI S DUMMER TL, Coos, NH

Built 1950 Load: 37.1 t ADT: 261

NH 43,NH107

Good

Over: LAMPREY RIVER

6.0 MI FROM RAYMOND TL, Rockingham, NH

Built 1984 Load: 37.1 t ADT: 6,447

NH 9

Good

Over: CONRAD ROAD

0.3 MI EAST SULLIVAN TL, Cheshire, NH

Built 1994 Load: 37.2 t ADT: 7,186

US 2

Good

Over: PEABODY RIVER

4.8 MI FROM RANDOLPH TL, Coos, NH

Built 1982 Load: 37.2 t ADT: 4,291

RIVERDALE ROAD

Good

Over: PISCATAQUOG RIVER

320 FT FR NEW BOSTON TL, Hillsborough, NH

Built 1940 Load: 37.2 t ADT: 627

BRIDGE STREET

Good

Over: SUNCOOK RIVER

0.3 MI FROM NH RTE 107, Merrimack, NH

Built 1909 Load: 37.2 t ADT: 90

NH101 WB

Good

Over: MAIN STREET

4.2MI E OF CANDIA TL, Rockingham, NH

Built 1982 Load: 37.2 t ADT: 20,577

US 3,NH 11

Good

Over: WINNISQUAM LAKE

SANBORNTON-BELMONT TL, Belknap, NH

Built 1973 Load: 37.6 t ADT: 16,081

NH 12A

Good

Over: GREAT BROOK

1.0 MI FROM CHARLESTOWN T, Sullivan, NH

Built 1949 Load: 37.6 t ADT: 943

I-93 NB

Good

Over: NH132

2.5MI S. TILTON T.L., Merrimack, NH

Built 1959 Load: 37.7 t ADT: 17,977

US 1 BYPASS

Good

Over: PISCATAQUA RIVER,RR

MAINE STATELINE, Rockingham, NH

Built 2017 Load: 37.8 t ADT: 10,864

Showing 1,551-1,600 of 2,542 bridges

Related

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Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges Editorial.

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). A "structurally deficient" rating is a repair-priority signal, not a closure or unsafe-to-cross designation. Consult a qualified civil engineer before making decisions based on this data.

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.