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

NH 25

Fair

Over: HALLS BROOK

200 FT FROM NH RTE 25, Grafton, NH

Built 1964 Load: 47.7 t ADT: 4,731

NH 43,NH107

Fair

Over: LAMPREY RIVER

0.1 MI FROM JCT RTE 107A, Rockingham, NH

Built 1989 Load: 47.7 t ADT: 7,000

US 3

Fair

Over: AMMONOOSUC RIVER

1.9 MI BETHLEHEM TL, Coos, NH

Built 1972 Load: 48.0 t ADT: 5,127

NH 12

Fair

Over: MAPLE AVENUE

2.5 MI SURRY TL, Cheshire, NH

Built 1966 Load: 48.1 t ADT: 10,707

CONNECTOR ROAD

Fair

Over: PEMIGEWASSET RIVER

.04 MI S.E. JCT US 3, Grafton, NH

Built 1937 Load: 48.1 t ADT: 3,252

VALLEY ROAD

Fair

Over: SNOWS BROOK

5.2 MI E THORNTONTTL TL, Grafton, NH

Built 1985 Load: 48.4 t ADT: 576

ALVAH WILSON ROAD

Fair

Over: GUNSTOCK RIVER

0.29 MI FR NH RTE 11A, Belknap, NH

Built 1973 Load: 48.6 t ADT: 480

NH110

Fair

Over: NORTH BRANCH BROOK

0.8 MI FROM DUMMER TL, Coos, NH

Built 1954 Load: 48.8 t ADT: 1,676

NH 25,NH118

Fair

Over: BAKER RIVER

AT WENTWORTH TOWNLINE, Grafton, NH

Built 2006 Load: 49.0 t ADT: 2,099

SECOND STREET

Fair

Over: PISCATAQUOG (NORTH BR)

0.2 MI N QUEEN CITY BRDGE, Hillsborough, NH

Built 1915 Load: 49.0 t ADT: 6,373

I-93 SB

Fair

Over: COTTAGE STREET

0.4 MI BETHLEHEM TL, Grafton, NH

Built 1959 Load: 49.9 t ADT: 5,432

I-93 NB

Fair

Over: COTTAGE STREET

0.4 MI BETHLEHEM TL, Grafton, NH

Built 1959 Load: 49.9 t ADT: 4,854

WINTER STREET

Fair

Over: ROARING BROOK

0.3 MI E NH RTE 110, Coos, NH

Built 1956 Load: 50.0 t ADT: 579

NH 16,SP TPK

Fair

Over: NEW BELLAMY LANE

0.6 MI FROM JCT. RT. 16, Strafford, NH

Built 1955 Load: 50.2 t ADT: 41,164

WASHINGTON STREET

Fair

Over: CANAL INLET

0.6 MI FR US 3, Merrimack, NH

Built 1975 Load: 50.4 t ADT: 2,781

OLD TROY ROAD

Fair

Over: BROOK

2.25MI. MARLBORO TL, Cheshire, NH

Built 1940 Load: 50.8 t ADT: 90

US 3

Fair

Over: MERRIMACK RIVER

0.1 MI EAST JCT I-93, Merrimack, NH

Built 1998 Load: 50.8 t ADT: 26,107

GROUT HILL ROAD

Fair

Over: COLD RIVER

202 FT FROM JCT NH123A, Sullivan, NH

Built 1930 Load: 51.0 t ADT: 90

RAMP E(CAMP ST)

Fair

Over: CSX

0.3 MI W JCT US 3, Hillsborough, NH

Built 1970 Load: 51.1 t ADT: 6,427

MILL ROAD

Fair

Over: EXETER RIVER

.10 MI FROM RT 111-A, Rockingham, NH

Built 1967 Load: 51.1 t ADT: 442

GREENFIELD PARKWAY

Fair

Over: RIDDLE BROOK

.1 WEST OF LIBERTY HILL R, Hillsborough, NH

Built 2000 Load: 51.2 t ADT: 538

MINE ROAD

Fair

Over: POUCHAUG BROOK

0.18MI MASS. SL, Cheshire, NH

Built 1994 Load: 51.4 t ADT: 322

FAIRGROUNDS ROAD

Fair

Over: WEST BRANCH BROOK

1.9 MI FROM NEWBURY TL, Merrimack, NH

Built 2001 Load: 51.7 t ADT: 394

NH 16

Fair

Over: BRANCH RIVER

3.5MI FROM MILTON T.L., Carroll, NH

Built 1959 Load: 51.8 t ADT: 9,869

NH135

Fair

Over: AMMONOOSUC RIVER

Bath and Haverhill TL, Grafton, NH

Built 1998 Load: 51.8 t ADT: 1,526

NH 10

Fair

Over: ASHUELOT RIVER

3.2 MI NORTH OF KEENE TL, Cheshire, NH

Built 1935 Load: 51.9 t ADT: 3,259

COLLINS STREET

Fair

Over: SQUAM RIVER

0.4 MI FR NH RTE 132, Grafton, NH

Built 1983 Load: 52.3 t ADT: 459

US302

Fair

Over: CRAWFORD BROOK

2.4Mi E Harts Locat.T/L, Coos, NH

Built 1965 Load: 52.4 t ADT: 3,804

LADIEU ROAD

Fair

Over: BLOODS BROOK

55 FT FR HOUSER LN, Sullivan, NH

Built 1920 Load: 52.7 t ADT: 90

NH 12

Fair

Over: TARBELL BROOK

0.5 MI FROM MASS SL, Cheshire, NH

Built 1958 Load: 53.3 t ADT: 4,685

PROSPECT STREET

Fair

Over: AMMONOOSUC RIVER

6.6 MI FROM LITTLETON TL, Grafton, NH

Built 1928 Load: 53.4 t ADT: 175

CILLEYVILLE ROAD

Fair

Over: BLACKWATER RIVER

0.6 MI NH 11, Merrimack, NH

Built 1934 Load: 53.5 t ADT: 255

NH 12,NH103

Fair

Over: RED WATER BROOK

2.3 MI FROM VT. SL, Sullivan, NH

Built 1997 Load: 53.5 t ADT: 9,498

NH 27

Fair

Over: BEAN BROOK

1.4MI JCT RT 27, Rockingham, NH

Built 1937 Load: 53.7 t ADT: 3,419

I-93 SB

Fair

Over: COAL HILL RD,GALE RIVER

1.9 MI SUGARHILL TL, Grafton, NH

Built 1959 Load: 54.2 t ADT: 2,599

NH113

Fair

Over: CHOCORUA RIVER

5.1 MI NE JCT 25 & 113, Carroll, NH

Built 1925 Load: 54.5 t ADT: 2,127

NH120

Fair

Over: GREAT BROOK

1.0 MI FROM PLAINFIELD TL, Grafton, NH

Built 1930 Load: 54.5 t ADT: 2,614

DURAND ROAD

Fair

Over: CARLTON BROOK

0.2 MI FROM US RTE2, Coos, NH

Built 2010 Load: 54.7 t ADT: 256

NO DATA ENTERED

Fair

Over: JACKMAN BROOK

MAP 36, Grafton, NH

Built 1993 Load: 54.8 t ADT: 99

SCHOOL STREET

Fair

Over: NHRR

0.1 MI FROM US 3, Belknap, NH

Built 1924 Load: 54.9 t ADT: 1,377

TROY ROAD

Fair

Over: SHAKER BROOK

1.3 MI. FROM TROY TL, Cheshire, NH

Built 1939 Load: 55.1 t ADT: 479

NH 10

Fair

Over: JACOBS BROOK

3.4 MI FROM LYME TL, Grafton, NH

Built 1938 Load: 55.2 t ADT: 1,348

I-93,FEE TPK SB

Fair

Over: CSX

.2 MI N OF JCT RT 3-A, Merrimack, NH

Built 1957 Load: 55.3 t ADT: 37,721

I-93 NB

Fair

Over: US302,NH 10,NH 18,NH116

.1 MI.NO. BETHLEHEM TL, Grafton, NH

Built 1959 Load: 55.5 t ADT: 4,854

US 4

Fair

Over: NHRR

.1 MI FROM JCT. I-93, Merrimack, NH

Built 1958 Load: 55.5 t ADT: 7,347

WATER STREET

Fair

Over: WEST BRANCH BROOK

.12 MI FROM OLD WARREN R, Merrimack, NH

Built 1980 Load: 55.7 t ADT: 330

RUSSELL STATION RD

Fair

Over: RAND BROOK

0.67MI. NEW BOSTON TL, Hillsborough, NH

Built 1930 Load: 56.0 t ADT: 90

NH152

Fair

Over: PISCASSIC RIVER

2.3 MI E LEE TL, Rockingham, NH

Built 1946 Load: 56.2 t ADT: 2,468

I-93 SB

Fair

Over: NH141

4.2 MI SUGARHILL TL, Grafton, NH

Built 1959 Load: 56.5 t ADT: 2,411

NH103

Fair

Over: ANDREW BROOK

2.1 MI FROM BRADFORD T.L., Merrimack, NH

Built 1962 Load: 56.7 t ADT: 4,506

Showing 1,151-1,200 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.