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

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

DORCHESTER ROAD

Fair

Over: GRANT BROOK

1.0 MI JCT ROUTE 10, Grafton, NH

Built 1940 Load: 28.1 t ADT: 1,110

US 4

Fair

Over: OYSTER RIVER

.2 MI FROM JCT RT 25, Strafford, NH

Built 1929 Load: 28.1 t ADT: 18,235

FDR 233

Fair

Over: BOG BROOK

MAP 23, Carroll, NH

Built 1977 Load: 28.2 t ADT: 99

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

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

NH 12

Fair

Over: MILL BROOK

1.73 MI FROM SURRY TL, Cheshire, NH

Built 1941 Load: 28.8 t ADT: 6,382

GALE CHANDLER ROAD

Fair

Over: MILL BROOK

100 FT FR BROOK RD, Grafton, NH

Built 1922 Load: 28.8 t ADT: 116

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

FDR 31

Fair

Over: EASTMAN BROOK

MAP 38, Grafton, NH

Built 1982 Load: 28.8 t ADT: 50

BURTON HIGHWAY

Fair

Over: BURTON POND OUTLET

TOWN RD, Hillsborough, NH

Built 1920 Load: 28.8 t ADT: 90

MAIN STREET

Fair

Over: SUNCOOK RIVER

1.3 MI N CHICHESTER TL, Merrimack, NH

Built 1942 Load: 28.8 t ADT: 4,344

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

GOULD HILL ROAD

Fair

Over: BOG POND OUTLET

1.5 MI FR MASCOMA RD, Merrimack, NH

Built 1950 Load: 28.9 t ADT: 90

US 3

Fair

Over: MOHAWK RIVER

1.3 MI NE COLUMBIA TL, Coos, NH

Built 1934 Load: 29.0 t ADT: 2,906

NH116,NH142

Fair

Over: BOG BROOK

0.1 MI FROM JCT ROUTE 3, Coos, NH

Built 1956 Load: 29.0 t ADT: 4,656

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

BROOK ROAD

Fair

Over: GUNNISON BROOK

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

Built 1945 Load: 29.0 t ADT: 991

NH 16

Fair

Over: BRANCH RIVER

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

Built 1966 Load: 29.2 t ADT: 12,702

SMITH RIVER ROAD

Fair

Over: SMITH RIVER

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

Built 1937 Load: 29.2 t ADT: 154

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

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

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

SIMONDSVILLE ROAD

Fair

Over: ASHUELOT RIVER

0.3 MI. RTE. 10, Cheshire, NH

Built 1969 Load: 29.4 t ADT: 100

NH 12

Fair

Over: MILL BROOK

2.5 MI TO WALPOLE TL, Cheshire, NH

Built 1948 Load: 29.4 t ADT: 6,382

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

I-89 NB

Fair

Over: BOG ROAD

1.4 MI FROM SUTTON TL, Merrimack, NH

Built 1967 Load: 29.4 t ADT: 9,607

WATERWORKS DRIVE

Fair

Over: CANAL OUTLET

NEAR JCT CANAL/COHAS AVES, Hillsborough, NH

Built 1940 Load: 29.6 t ADT: 25

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

I-93 SB

Fair

Over: NH132

3.0 MI FROM MEREDITH TL, Belknap, NH

Built 1963 Load: 29.8 t ADT: 10,717

I-93 SB

Fair

Over: NH132

5.2 MI MEREDITH TL, Belknap, NH

Built 1964 Load: 29.8 t ADT: 10,717

NH 26

Fair

Over: CONNECTICUT RIVER

VERMONT STATE LINE, Coos, NH

Built 1953 Load: 29.8 t ADT: 907

NH112

Fair

Over: HANCOCK BROOK

3.1 MI E OF LIVERMORE TL, Grafton, NH

Built 1942 Load: 29.8 t ADT: 3,061

UPPER MAD RIVER RD

Fair

Over: MAD RIVER

150 FT FR NH RTE 49, Grafton, NH

Built 1978 Load: 29.8 t ADT: 434

NH 77

Fair

Over: CANAL 2 CHOATE BK

1.0 MI W DUNBARTON T.L., Hillsborough, NH

Built 1960 Load: 29.8 t ADT: 4,595

I-89 NB

Fair

Over: WARNER RIVER

6.2 MI HOPKINTON TL, Merrimack, NH

Built 1966 Load: 29.8 t ADT: 10,670

I-89 SB

Fair

Over: WARNER RIVER

3.3 MI HOPKINTON T.L., Merrimack, NH

Built 1966 Load: 29.8 t ADT: 11,265

NH119

Fair

Over: CANAL

.59 MI. W. WINCHESTER TL, Cheshire, NH

Built 1953 Load: 29.9 t ADT: 3,055

Showing 751-800 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.