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

NH118

Poor

Over: INDIAN RIVER

2.3 MI FROM DORCHESTER TL, Grafton, NH

Built 1948 Load: 28.1 t ADT: 1,408

NH 16,SP TPK SB

Poor

Over: COCHECO RIVER

3.6 MI. FROM ROCHESTER TL, Strafford, NH

Built 1957 Load: 28.4 t ADT: 23,076

NH 16,SP TPK NB

Poor

Over: COCHECO RIVER

3.6 MI FROM ROCHESTER TL., Strafford, NH

Built 1957 Load: 28.4 t ADT: 22,053

NH111A

Poor

Over: EXETER RIVER

0.6 MI DANVILLE T.L., Rockingham, NH

Built 1978 Load: 28.8 t ADT: 3,186

NH175

Poor

Over: PEMIGEWASSET RIVER

0.6 MI EAST JCT US 3, Grafton, NH

Built 1976 Load: 28.9 t ADT: 672

ANTRIM ROAD

Poor

Over: MONADNOCK MILL CANAL

0.39 MI FR CONTOOCOOK VA, Hillsborough, NH

Built 1922 Load: 28.9 t ADT: 2,291

RIVER ROAD SOUTH

Poor

Over: PARTRIDGE BROOK

0.72 MI NH63, Cheshire, NH

Built 1937 Load: 29.2 t ADT: 1,214

US 3

Poor

Over: BOG BROOK

1.2 MI FROM PLYMOUTH TL, Grafton, NH

Built 1929 Load: 29.4 t ADT: 1,326

NH 11

Poor

Over: MERRYMEETING RIVER

8.5 MI FROM GILFORD TL, Belknap, NH

Built 1934 Load: 30.6 t ADT: 10,193

PERCH POND ROAD

Poor

Over: RYAN BROOK

1.9 MI FR HOLDERNESS TL, Grafton, NH

Built 1940 Load: 30.7 t ADT: 90

NH 12

Poor

Over: NECRR

4.9 MI. FROM WALPOLE TL, Sullivan, NH

Built 1959 Load: 31.0 t ADT: 3,766

NH 25A

Poor

Over: BRACKETT BROOK

9.9 MI FROM VERMONT SL, Grafton, NH

Built 1929 Load: 32.3 t ADT: 805

NH 11

Poor

Over: SUCKER BROOK

.3 MI FROM FRANKLIN T.L., Merrimack, NH

Built 1929 Load: 32.3 t ADT: 2,622

NH120,PARK LOT,PED

Poor

Over: NHRR(ABD)

.1 MI FROM JCT RTE 4, Grafton, NH

Built 1969 Load: 32.7 t ADT: 7,709

NH 18

Poor

Over: CONNECTICUT RIVER

NH-VT SL, Grafton, NH

Built 1934 Load: 32.7 t ADT: 1,486

NH 49

Poor

Over: MAD RIVER

1.9 MI SW WATERVILLE T L, Grafton, NH

Built 1979 Load: 32.7 t ADT: 2,786

BEALS ROAD

Poor

Over: BABOOSIC BROOK

33 FT FR MERRIMACK TL, Hillsborough, NH

Built 1928 Load: 32.7 t ADT: 481

HALL ROAD

Poor

Over: LITTLE COHAS BROOK

0.73 MI FR HARVEY RD, Rockingham, NH

Built 1974 Load: 32.7 t ADT: 1,920

PLAINS ROAD

Poor

Over: SUGAR RIVER

0.1 MI JCT RTE 12, Sullivan, NH

Built 1974 Load: 32.7 t ADT: 1,356

US 4,MECHANIC ST

Poor

Over: MASCOMA RIVER

5.4 MI FROM HANOVER TL, Grafton, NH

Built 1977 Load: 32.8 t ADT: 12,552

DUPAW GOULD ROAD

Poor

Over: LANCY BROOK

1.4 MI FR MCINTOSH RD, Hillsborough, NH

Built 1987 Load: 33.0 t ADT: 443

SPRING STREET

Poor

Over: COCHECO RIVER

1.38MI RTE 11, Strafford, NH

Built 1926 Load: 33.5 t ADT: 759

I-89 SB

Poor

Over: CONNECTICUT RIVER,NECRR

0.04 MI FROM VT. SL., Grafton, NH

Built 1966 Load: 33.8 t ADT: 20,851

I-89 NB

Poor

Over: CONNECTICUT RIVER,NECRR

0.04 MI FROM VT SL., Grafton, NH

Built 1966 Load: 33.8 t ADT: 21,851

LAST STREET

Poor

Over: SUCKER BROOK

0.03 MI NH 11, Merrimack, NH

Built 1936 Load: 35.9 t ADT: 90

NH 11

Poor

Over: POOR FARM BROOK

1.7 MI S ALTON TL, Belknap, NH

Built 1966 Load: 37.2 t ADT: 5,454

TIRRELL HILL ROAD

Poor

Over: BLACK BROOK

1.9MI Fr Goffstwn Back RD, Hillsborough, NH

Built 1994 Load: 37.2 t ADT: 1,273

FDR 304

Poor

Over: LITTLE RIVER

MAP 10, Grafton, NH

Built 1975 Load: 37.3 t ADT: 50

RECYCLE WAY

Poor

Over: ASHUELOT RIVER

0.04MI NH119, Cheshire, NH

Built 1947 Load: 37.6 t ADT: 25

SCHOOL STREET

Poor

Over: AMMONOOSUC RIVER

214 FT FROM NH RTE 112, Grafton, NH

Built 1960 Load: 38.1 t ADT: 1,702

NH119

Poor

Over: CONNECTICUT RIVER

0.3 MI E VERMONT SL, Cheshire, NH

Built 1920 Load: 38.6 t ADT: 8,409

NH 31

Poor

Over: STONY BROOK

0.1 MI FM LYNDEBOROUGH TL, Hillsborough, NH

Built 1929 Load: 39.2 t ADT: 3,444

SHEPARD HOME ROAD

Poor

Over: EXETER RIVER

0.8MI. NH102, Rockingham, NH

Built 1986 Load: 39.2 t ADT: 446

WASHBURN ROAD

Poor

Over: PATTEN BROOK

8.11 MI FROM E HILL RD, Grafton, NH

Built 1950 Load: 44.7 t ADT: 314

BROOK ROAD

Poor

Over: SALMON BROOK

0.1 MI FROM HALE RD, Belknap, NH

Built 1900 Load: 45.4 t ADT: 90

I-89 SB

Poor

Over: TURKEY POND

1.5 MI NW JCT RT 13, Merrimack, NH

Built 1959 Load: 47.4 t ADT: 19,873

I-89 NB

Poor

Over: TURKEY POND

1.5 MI NW OF JCT RT 13, Merrimack, NH

Built 1959 Load: 47.4 t ADT: 19,523

FRYE MILL ROAD

Poor

Over: BURTON POND OUTLET

1.2Mi.Fr.Issac Frye Hwy., Hillsborough, NH

Built 1920 Load: 51.8 t ADT: 35

CARLETON HILL ROAD

Poor

Over: MOHAWK RIVER

0.15 MI SE JCT NH 26, Coos, NH

Built 1935 Load: 55.1 t ADT: 425

GRANITE ROAD

Structurally Deficient

Over: SOUTH RIVER

0.3MI. RTE 153, Carroll, NH

Built 1920 ADT: 90

MAPLE STREET

Structurally Deficient

Over: BRANCH RIVER

0.02MI. RTE 153, Carroll, NH

Built 1940 ADT: 90

WHIPPLE HILL ROAD

Structurally Deficient

Over: ROARING BROOK

0.5 MI. RTE.119, Cheshire, NH

Built 1950 ADT: 331

CHRISTIAN HILL RD

Structurally Deficient

Over: NHRR(ABD)

50 FT FROM SOUTH GROVE S, Cheshire, NH

Built 1930 ADT: 2,159

BRIDGE STREET

Structurally Deficient

Over: CONNECTICUT RIVER

VERMONT STATE LINE, Cheshire, NH

Built 1930 ADT: 6,100

GRIST MILL HILL RD

Structurally Deficient

Over: INDIAN RIVER

2.01 MI FROM GRAFTON TL, Grafton, NH

Built 1956 ADT: 404

HIGH BRIDGE ROAD

Structurally Deficient

Over: ARCHERTOWN BROOK

150FT W TILLOTSON RD JCT, Grafton, NH

Built 1940 ADT: 90

THORNTONS FERRY RD

Structurally Deficient

Over: BEAVER BROOK

3.2 MI FR MERRIMACK TL, Hillsborough, NH

Built 1970 ADT: 388

OLD COUNTY RD N

Structurally Deficient

Over: COLLINS BROOK

2.4 MI. DEERING TL, Hillsborough, NH

Built 1981 ADT: 90

DOUGHERTY LANE

Structurally Deficient

Over: MID BR PISCATAQUOG RIVER

0.8 MI FR SANDERS HILL R, Hillsborough, NH

Built 2004 ADT: 90

TOWNHOUSE ROAD

Structurally Deficient

Over: NORTHEAST POND

NH-ME SL, Strafford, NH

Built 1948 ADT: 554

Showing 2,451-2,500 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.