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

US302

Fair

Over: CONNECTICUT RIVER

VERMONT STATE LINE, Grafton, NH

Built 1928 Load: 32.7 t ADT: 7,331

US302,NH 10

Fair

Over: MILL BROOK

0.1 MI EAST OF BATH TL, Grafton, NH

Built 1930 Load: 32.7 t ADT: 3,021

US302,NH 10

Fair

Over: NHRR(ABD)

2.9 MI LANDAFF TL, Grafton, NH

Built 1979 Load: 32.7 t ADT: 5,186

ASH HILL ROAD

Fair

Over: PETTYBORO BROOK

1.9 MI FR LISBON TL, Grafton, NH

Built 1984 Load: 32.7 t ADT: 90

RIVER ROAD

Fair

Over: GRANT BROOK

2.6 MI FR HANOVER TL, Grafton, NH

Built 1978 Load: 32.7 t ADT: 340

EASTMAN ROAD

Fair

Over: ORANGE BROOK

0.08 MI FR CANAAN TL, Grafton, NH

Built 1976 Load: 32.7 t ADT: 55

TOWN ROAD #79

Fair

Over: JACOBS BROOK

125 FT. RTE. 25A, Grafton, NH

Built 1930 Load: 32.7 t ADT: 52

NH 25A

Fair

Over: JACOBS BROOK

4.1 MI FROM VERMONT SL, Grafton, NH

Built 1925 Load: 32.7 t ADT: 1,269

STUDIO ROAD

Fair

Over: BAKER RIVER

0.10MI NH25, Grafton, NH

Built 1976 Load: 32.7 t ADT: 123

BOSTON POST ROAD

Fair

Over: SOUHEGAN RIVER

1.9 MI MERRIMACK TL, Hillsborough, NH

Built 1977 Load: 32.7 t ADT: 4,310

NH 13

Fair

Over: NISSITISSIT RIVER

.9 MI FROM MASS. S.L., Hillsborough, NH

Built 1947 Load: 32.7 t ADT: 6,532

BARTLETT HILL ROAD

Fair

Over: PISCATAQUOG RIVER

2.0MI WEARE TL, Hillsborough, NH

Built 1930 Load: 32.7 t ADT: 90

MILL STREET

Fair

Over: SOUHEGAN RIVER

0.17 MI W JCT NH 31, Hillsborough, NH

Built 1925 Load: 32.7 t ADT: 1,020

NH111 WB

Fair

Over: MERRIMACK RIVER

.1 MI WEST OF JCT RT 3A, Hillsborough, NH

Built 1970 Load: 32.7 t ADT: 16,887

NH111 EB

Fair

Over: MERRIMACK RIVER

.1 MI WEST OF JCT RT 3-A, Hillsborough, NH

Built 1973 Load: 32.7 t ADT: 15,264

I-93 NB

Fair

Over: MERRIMACK RIVER,CSX,RD

AT MANCHESTER-HOOKSETT TL, Hillsborough, NH

Built 1976 Load: 32.7 t ADT: 47,411

I-93 SB

Fair

Over: MERRIMACK RIVER,CSX,RD

MANCHESTER-HOOKSETT TL, Hillsborough, NH

Built 1976 Load: 32.7 t ADT: 33,486

RIVER ROAD

Fair

Over: PISCATAQUOG RIVER

1.8 MI N JCT RT 114, Hillsborough, NH

Built 1964 Load: 32.7 t ADT: 1,214

CLOUGH PARK ROAD

Fair

Over: PISCATAQUOG RIVER

1.0 MI S DUNBARTON TL, Hillsborough, NH

Built 1962 Load: 32.7 t ADT: 533

WEBSTER MILLS ROAD

Fair

Over: SUNCOOK RIVER

AT PITTSFIELD T/L, Merrimack, NH

Built 1981 Load: 32.7 t ADT: 1,036

HORSE HILL ROAD

Fair

Over: CONTOOCOOK RIVER

220 FEET FROM BOG RD, Merrimack, NH

Built 1981 Load: 32.7 t ADT: 2,903

NH 9

Fair

Over: SOUCOOK RIVER

PEMBROKE TL, Merrimack, NH

Built 1936 Load: 32.7 t ADT: 9,207

NORTH VILLAGE ROAD

Fair

Over: WARNER RIVER

0.05 MI FROM I-89, Merrimack, NH

Built 1967 Load: 32.7 t ADT: 783

NH108

Fair

Over: CSX

NEWMARKET TL, Rockingham, NH

Built 1936 Load: 32.7 t ADT: 16,190

NH108

Fair

Over: CSX

NEWFIELDS T.L., Rockingham, NH

Built 1936 Load: 32.7 t ADT: 16,190

NH108

Fair

Over: LAMPREY RIVER

.4 MI FROM JCT. RT. 152, Rockingham, NH

Built 1955 Load: 32.7 t ADT: 10,461

NH 1B

Fair

Over: PISCATAQUA ESTUARY

1.3 MI FROM JCT RT 1, Rockingham, NH

Built 1955 Load: 32.7 t ADT: 2,973

NH 28 (S BROADWAY)

Fair

Over: SPICKET RIVER

1.1MI N. OF MASS SL, Rockingham, NH

Built 1900 Load: 32.7 t ADT: 19,774

NH286

Fair

Over: CSX(ABD)

AT MASS S.L., Rockingham, NH

Built 1940 Load: 32.7 t ADT: 6,933

CHESTNUT STREET

Fair

Over: COCHECO RIVER

800 FT SW JCT 4&16, Strafford, NH

Built 1975 Load: 32.7 t ADT: 12,522

MILL ROAD

Fair

Over: CSX

TOWN RD, Strafford, NH

Built 1973 Load: 32.7 t ADT: 1,348

LEE HOOK ROAD

Fair

Over: LAMPREY RIVER

.6 MI SE JCT 155, Strafford, NH

Built 1923 Load: 32.7 t ADT: 1,593

NH 16,SP TPK

Fair

Over: NH125

7.8 MI N OF ROCHESTER TL, Strafford, NH

Built 1981 Load: 32.7 t ADT: 14,784

SALMON FALLS ROAD

Fair

Over: SALMON FALLS RIVER

MAINE STATE LINE RD 5, Strafford, NH

Built 1969 Load: 32.7 t ADT: 4,946

BERYL MT ROAD

Fair

Over: COLD RIVER

0.04 MI FROM RTE 123-A, Sullivan, NH

Built 1977 Load: 32.7 t ADT: 90

NH 11

Fair

Over: CONNECTICUT RIVER

NH VT STATE LINE, Sullivan, NH

Built 1900 Load: 32.7 t ADT: 7,028

NH 11

Fair

Over: NECRR

0.7 MI. EAST VT. SL, Sullivan, NH

Built 1965 Load: 32.7 t ADT: 2,891

RED WATER BROOK RD

Fair

Over: RED WATER BROOK

0.3 MI NH 120, Sullivan, NH

Built 1935 Load: 32.7 t ADT: 90

WHITEWATER BK RD

Fair

Over: RED WATER BROOK

0.3 MI CORNISH TL, Sullivan, NH

Built 1930 Load: 32.7 t ADT: 90

NH 10

Fair

Over: CROYDON BRANCH SUGAR R

0.06 MI. FROM NEWPORT TL, Sullivan, NH

Built 1973 Load: 32.7 t ADT: 3,559

CRANE BROOK ROAD

Fair

Over: COLD RIVER

0.5MI WEST OF ACWORTH TL, Sullivan, NH

Built 1964 Load: 32.7 t ADT: 364

OAK STREET

Fair

Over: SUGAR RIVER

0.5 MI FR NO. NEWPORT RD, Sullivan, NH

Built 1979 Load: 32.7 t ADT: 947

BELKNAP AVENUE

Fair

Over: SUGAR RIVER

0.2 MI FR NO. MAIN ST, Sullivan, NH

Built 1974 Load: 32.7 t ADT: 1,321

NH 11 RAMP

Fair

Over: SUGAR RIVER

0.1 MI FROM NEWPORT TL, Sullivan, NH

Built 1923 Load: 32.7 t ADT: 1,463

I-93 SB

Fair

Over: TRIPOLI ROAD

3.46 MI LINCOLN TL, Grafton, NH

Built 1972 Load: 33.0 t ADT: 7,060

I-93 NB

Fair

Over: TRIPOLI ROAD

3.46 MI LINCOLN TL, Grafton, NH

Built 1972 Load: 33.0 t ADT: 6,913

NH125

Fair

Over: COCHECO RIVER

.7 MI JCT RT 16, Strafford, NH

Built 1931 Load: 33.0 t ADT: 16,118

DENMAN THOMPSON HW

Fair

Over: ASHUELOT RIVER

0.19 MI FR WINCHESTER ST, Cheshire, NH

Built 1976 Load: 33.1 t ADT: 1,445

ELM STREET

Fair

Over: ASHUELOT RIVER

ADJACENT NH 119, Cheshire, NH

Built 1921 Load: 33.1 t ADT: 2,163

NH 16

Fair

Over: NEW RIVER

.3 MI. N. OF JACKSON TL, Coos, NH

Built 1955 Load: 33.1 t ADT: 3,513

Showing 901-950 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.