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 SB

Fair

Over: US302,NH 10,NH 18,NH116

0.03 MI LITTLETON TL, Grafton, NH

Built 1959 Load: 36.1 t ADT: 4,228

GILMAN VALLEY ROAD

Fair

Over: STONY BROOK

0.3 MI. OSSIPEE TL, Carroll, NH

Built 1930 Load: 36.3 t ADT: 90

NH110

Fair

Over: ROARING BROOK

2.4 MI FROM STARK TL, Coos, NH

Built 1962 Load: 36.3 t ADT: 2,271

BOSTON POST ROAD

Fair

Over: BEAVER BROOK

.06 MI FR NH RTE 122, Hillsborough, NH

Built 1984 Load: 36.3 t ADT: 3,484

GARRISON LANE

Fair

Over: LITTLE RIVER

0.6MI RTE 111A, Rockingham, NH

Built 1930 Load: 36.3 t ADT: 13

FRENCH ROAD

Fair

Over: JOHNS RIVER

2.9 MI NH 135, Coos, NH

Built 1948 Load: 36.4 t ADT: 207

BOG ROAD

Fair

Over: PATTEN BROOK

0.5MI S ALEXANDRIA CTR, Grafton, NH

Built 1950 Load: 36.4 t ADT: 90

NH 45

Fair

Over: SOUHEGAN RIVER

3.21 MI. N.OF MASON TL, Hillsborough, NH

Built 1937 Load: 36.6 t ADT: 2,660

NH 33

Fair

Over: WINNICUT RIVER

1.4 MI FROM STRATHAM TL, Rockingham, NH

Built 1959 Load: 36.7 t ADT: 19,151

BALL PARK ROAD

Fair

Over: TROW BROOK

0.09MI. LEMPSTER TL, Sullivan, NH

Built 1930 Load: 36.9 t ADT: 90

US302

Fair

Over: SACO RIVER

2.4 MI E JCT 16, Carroll, NH

Built 1972 Load: 37.1 t ADT: 13,181

NH 27

Fair

Over: NORTH BRANCH RIVER

.2 MI FROM RAYMOND TL, Rockingham, NH

Built 1932 Load: 37.2 t ADT: 3,419

US 1 NB RAMP

Fair

Over: NHRR(ABD)

.1 MI FROM JCT. RT 1, Rockingham, NH

Built 1963 Load: 37.2 t ADT: 10,526

BRANCH ROAD

Fair

Over: MINNEWAWA RIVER

0.02 MI N JCT NH10, Cheshire, NH

Built 1938 Load: 37.4 t ADT: 1,004

CENTRE ST

Fair

Over: OTTER BROOK

4.46 MI GILSUM TL., Cheshire, NH

Built 1981 Load: 37.4 t ADT: 631

MASON STREET

Fair

Over: CANAL

610FT WEST OF UNITY ST, Coos, NH

Built 1967 Load: 37.4 t ADT: 5,273

NH120

Fair

Over: MASCOMA RIVER

0.7 MI FROM JCT I-89, Grafton, NH

Built 1969 Load: 37.4 t ADT: 7,709

I-95 RAMPS

Fair

Over: HODGSON BROOK

SP TPK,I-95 INTERCHANGE, Rockingham, NH

Built 1956 Load: 37.7 t ADT: 15,259

US 4

Fair

Over: STONY BROOK

2.8 MI. FROM ENFIELD T.L., Grafton, NH

Built 1966 Load: 37.9 t ADT: 12,195

NH123A

Fair

Over: WEST BR SOUHEGAN RIVER

1.78 MI N MASS SL, Hillsborough, NH

Built 1936 Load: 37.9 t ADT: 1,250

NH116

Fair

Over: WILD AMMONOOSUC RIVER

.02 MI S JCT. 112, Grafton, NH

Built 1927 Load: 38.1 t ADT: 865

DAME HILL ROAD

Fair

Over: JACOBS BROOK

100 FT E. OF JCT NH 25-A, Grafton, NH

Built 1947 Load: 38.1 t ADT: 251

FDR 13

Fair

Over: UPPER AMMONOOSUC RIVER

MAP 02, Coos, NH

Built 1947 Load: 38.2 t ADT: 50

HUNTRESS BRIDGE RD

Fair

Over: OSSIPEE RIVER

FREEDOM TL, Carroll, NH

Built 1936 Load: 38.4 t ADT: 180

MASON STREET

Fair

Over: ANDROSCOGGIN RIVER

350FT WEST OF UNITY ST, Coos, NH

Built 1967 Load: 38.4 t ADT: 5,273

CAMP ROAD

Fair

Over: NEWTON BROOK

1.3 MI FROM CORNISH TL, Sullivan, NH

Built 2018 Load: 38.4 t ADT: 90

EAST DUNBARTON RD

Fair

Over: BLACK BROOK

TOWN RD, Hillsborough, NH

Built 1994 Load: 38.6 t ADT: 1,555

I-89 SB

Fair

Over: STOCKER BROOK

.81 MI SPRINGFIELD TL, Sullivan, NH

Built 1967 Load: 38.6 t ADT: 9,549

NH115A

Fair

Over: ISRAEL RIVER

2.4 MI SW JCT US 2, Coos, NH

Built 1973 Load: 38.7 t ADT: 819

PODUNK ROAD

Fair

Over: BEAR BROOK

BEAR BROOK RESERVATION, Merrimack, NH

Built 1950 Load: 38.7 t ADT: 398

WESTERN AVE

Fair

Over: CANAL

2.9 MI FR HILLSBOROUGH T, Merrimack, NH

Built 1929 Load: 38.8 t ADT: 90

I-293 SB,NH101 EB

Fair

Over: MERRIMACK RIVER,CSX

MANCHESTER TL, Hillsborough, NH

Built 1960 Load: 39.0 t ADT: 40,972

I-293 NB,NH101 WB

Fair

Over: MERRIMACK RIVER,CSX

MANCHESTER TL, Hillsborough, NH

Built 1960 Load: 39.0 t ADT: 43,021

US202

Fair

Over: MOOSE BROOK

1.0 MI GREENFIELD TL, Hillsborough, NH

Built 1959 Load: 39.0 t ADT: 5,702

NH101

Fair

Over: PERRY ROAD

0.3 MI W JCT RTE 13, Hillsborough, NH

Built 1978 Load: 39.0 t ADT: 17,139

NH 12A

Fair

Over: LITTLE SUGAR RIVER

0.6 MI NW JCT 12 AND 12A, Sullivan, NH

Built 1984 Load: 39.0 t ADT: 1,438

CROSS ROAD

Fair

Over: EXETER RIVER

AT BRENTWOOD TL, Rockingham, NH

Built 1930 Load: 39.2 t ADT: 1,008

COOLEDGE ROAD

Fair

Over: BEARDS BROOK

3.2 MI FR NH RTE 31, Hillsborough, NH

Built 1970 Load: 39.4 t ADT: 90

US 1 SB

Fair

Over: NHRR(ABD)

.1 MI. FROM JCT RT 101 BY, Rockingham, NH

Built 1936 Load: 39.4 t ADT: 11,366

US202,NH 9

Fair

Over: AMEY BROOK

.4 MI EAST JCT RT 114, Merrimack, NH

Built 1962 Load: 39.5 t ADT: 15,572

CRYSTAL LAKE ROAD

Fair

Over: SUNCOOK RIVER

0.4 MI NW JCT TOWN ROAD94, Belknap, NH

Built 1929 Load: 39.6 t ADT: 1,242

US 4

Fair

Over: MILL BROOK

1.25 MI FROM DANBURY TL, Grafton, NH

Built 1948 Load: 39.6 t ADT: 1,674

EAST PENACOOK ROAD

Fair

Over: BLACKWATER RIVER

1.4 MI FR CONCORD TL, Merrimack, NH

Built 1967 Load: 39.6 t ADT: 1,627

HENRY BRIDGE ROAD

Fair

Over: PISCATAQUOG RIVER

3.0 MI FROM BEDFORD TL, Hillsborough, NH

Built 1937 Load: 39.9 t ADT: 6,725

US 3 BUS,NH107

Fair

Over: BLACK BROOK

3.75 MI N BELMONT TL, Belknap, NH

Built 1975 Load: 40.0 t ADT: 14,041

I-93 PARKWAY SB

Fair

Over: TRAIL,PEMIGEWASSET RIVER

5.1 MI NO WOODSTOCK TL, Grafton, NH

Built 1986 Load: 40.0 t ADT: 5,704

BEAN BROOK ROAD

Fair

Over: BEAN BROOK

0.27 MI. RTE.10, Grafton, NH

Built 2009 Load: 40.2 t ADT: 90

NH 10

Fair

Over: SAWYER BROOK

2.2 MI. FROM CROYDON TL, Sullivan, NH

Built 1968 Load: 40.2 t ADT: 6,794

NH113

Fair

Over: CHANDLER BROOK

3.0 MI S OF MAINE SL, Carroll, NH

Built 1931 Load: 40.4 t ADT: 343

PENACOOK ROAD

Fair

Over: CONTOOCOOK RIVER

1.0 MI FR WEBSTER TL, Merrimack, NH

Built 1980 Load: 40.4 t ADT: 1,218

Showing 1,001-1,050 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.