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-393,US 4,US202E

Good

Over: HORSE CORNER ROAD

0.01 MI W NH 9, Merrimack, NH

Built 1988 Load: 60.8 t ADT: 8,399

US 3

Good

Over: BEAVER BROOK

3.9 MI S STEWARTSTOWN TL, Coos, NH

Built 1929 Load: 60.9 t ADT: 2,906

US 4,US202,NH 9

Good

Over: SUNCOOK RIVER OVERFLOW

.4 MI EAST JCT. RT 28, Merrimack, NH

Built 1996 Load: 60.9 t ADT: 16,677

I-93 SB

Good

Over: EUSTIS HILL ROAD

0.6 MI BETHLEHEM TL, Grafton, NH

Built 1959 Load: 61.2 t ADT: 4,433

NH107

Good

Over: EXETER RIVER

FREMONT-BRENTWOOD TL, Rockingham, NH

Built 1988 Load: 61.6 t ADT: 4,966

BELKNAP MT ROAD

Good

Over: GUNSTOCK RIVER

100' SOUTH NH 11-A, Belknap, NH

Built 1900 Load: 61.9 t ADT: 989

SEWALLS FALLS ROAD

Good

Over: MERRIMACK RIVER

0.3 MI JCT RTE 132, Merrimack, NH

Built 2016 Load: 61.9 t ADT: 3,625

HANCOCK ROAD

Good

Over: SKATUTAKEE LAKE

TOWN RD, Cheshire, NH

Built 1960 Load: 62.1 t ADT: 600

PROVINCE ROAD

Good

Over: SUNCOOK RIVER

210 FT FR NH RTE 28, Belknap, NH

Built 1998 Load: 62.6 t ADT: 90

CASCADE STREET

Good

Over: SL&ARR

AT BERLIN GORHAM TL, Coos, NH

Built 1999 Load: 62.6 t ADT: 480

NH 10

Good

Over: S BRANCH SUGAR RIVER

0.6 MI FROM LEMPSTER TL, Sullivan, NH

Built 1928 Load: 62.6 t ADT: 1,887

US 4 WB

Good

Over: SP TPK,NH 16

0.4 MI JCT US 4, Strafford, NH

Built 2020 Load: 62.7 t ADT: 14,038

WATER STREET

Good

Over: JOHNS RIVER

0.05 MI FROM BROWN ST, Coos, NH

Built 1932 Load: 62.9 t ADT: 116

I-93 SB

Good

Over: WEST ROAD

3.1 MI NO. CONCORD T.L., Merrimack, NH

Built 1960 Load: 63.0 t ADT: 18,528

I-93 NB

Good

Over: WEST ROAD

3.1 MI NO. CONCORD T.L., Merrimack, NH

Built 1960 Load: 63.0 t ADT: 18,873

WEST STREET

Good

Over: GREAT BROOK

0.05MI FROM NH31, Hillsborough, NH

Built 2019 Load: 63.5 t ADT: 90

SCHOOLHOUSE LANE

Good

Over: MINK BROOK

0.9 MI FROM GREENSBORO R, Grafton, NH

Built 1981 Load: 64.7 t ADT: 480

NH123

Good

Over: WARREN BROOK

2.86 MI. SE JCT. NH 123-A, Cheshire, NH

Built 2012 Load: 65.1 t ADT: 1,253

I-93 NB

Good

Over: NHRR,WINNIPESAUKEE RIVER

TILTON TL, Merrimack, NH

Built 1960 Load: 65.2 t ADT: 15,272

WISWALL ROAD

Good

Over: LAMPREY RIVER

0.6 MI. LEE TL, Strafford, NH

Built 2010 Load: 65.6 t ADT: 253

CONVERSE ROAD

Good

Over: WHITING BROOK

TOWN RD, Hillsborough, NH

Built 2015 Load: 65.7 t ADT: 90

NORTH SHORE ROAD

Good

Over: GEORGES BROOK

0.41 MI. FROM JCT. 3-A, Grafton, NH

Built 1900 Load: 65.8 t ADT: 1,214

US 3 BUS,NH 11A

Good

Over: DURKEE BROOK

.4 MI N.E. BELMONT T.L., Belknap, NH

Built 2022 Load: 66.1 t ADT: 12,884

NH 28,NH109

Good

Over: SMITH RIVER

3.5 MI FROM ALTON TL, Carroll, NH

Built 1935 Load: 66.3 t ADT: 8,679

NH140

Good

Over: WINNIPESAUKEE RIVER

0.4 MI S JCT RTE 3, Belknap, NH

Built 1968 Load: 66.6 t ADT: 10,577

NH 16

Good

Over: SESSIONS BROOK

1.1 MI S CAMBRIDGE TL, Coos, NH

Built 1926 Load: 67.1 t ADT: 1,514

I-93 SB

Good

Over: BEAVER BROOK

Derry T/L, Rockingham, NH

Built 2020 Load: 67.1 t ADT: 40,312

NH 11

Good

Over: SUGAR RIVER

6.1 MI. FROM NEW LONDON T, Sullivan, NH

Built 1957 Load: 67.3 t ADT: 6,479

FEE TPK,N&S RAMPS

Good

Over: SALMON BROOK

3.3 MI N MASS SL, Hillsborough, NH

Built 1955 Load: 67.9 t ADT: 125,991

BALSAMS BK DR PVT

Good

Over: BALSAM POND BROOK

0.3 MI WEST OF DIXVILLE, Coos, NH

Built 2008 Load: 68.1 t ADT: 20

NH155

Good

Over: CSX

1.4 MI FROM DURHAM TL, Strafford, NH

Built 2007 Load: 68.2 t ADT: 10,245

PLEASANT VALLEY RD

Good

Over: HEATH BROOK

0.95 MILES FROM NH 28, Carroll, NH

Built 2020 Load: 68.4 t ADT: 1,017

CASS MILL ROAD

Good

Over: SMITH RIVER

AT ALEXANDRIA TL, Merrimack, NH

Built 2000 Load: 68.9 t ADT: 90

I-93 SB

Good

Over: NHRR,WINNIPESAUKEE RIVER

TILTON TL, Merrimack, NH

Built 1960 Load: 68.9 t ADT: 15,211

COLLEGE ROAD

Good

Over: WILLEY BROOK

0.42MI NH28, Carroll, NH

Built 2002 Load: 69.4 t ADT: 569

NH 25,NH118

Good

Over: BAKER RIVER

2.0 MI FROM RUMNEY TL, Grafton, NH

Built 1960 Load: 69.6 t ADT: 3,351

WILDER ROAD

Good

Over: NUBANUSIT BROOK

0.1 MI FR MAIN ST, Hillsborough, NH

Built 2004 Load: 69.7 t ADT: 272

TOWN FARM ROAD

Good

Over: SPICKET RIVER

1.10 MI FROM MASS. SL, Rockingham, NH

Built 2016 Load: 69.8 t ADT: 3,511

LONGVIEW ROAD

Good

Over: MOOSE BROOK

.08 MI FROM NH RTE 123, Hillsborough, NH

Built 1930 Load: 70.2 t ADT: 425

CAVENDER ROAD

Good

Over: FERGUSON BROOK

0.4 MI FR GREENFIELD TL, Hillsborough, NH

Built 2006 Load: 70.2 t ADT: 90

EAST SURRY ROAD

Good

Over: STURTEVANT BROOK

1.0MI. TL SURRY, Cheshire, NH

Built 2012 Load: 70.9 t ADT: 817

NH116

Good

Over: WHITCHER BROOK

2 MI E HAVERHILL TL, Grafton, NH

Built 2003 Load: 70.9 t ADT: 1,214

NH 16,NH 25

Good

Over: CHOCORUA RIVER

0.8 MI. TAMWORTH T.L., Carroll, NH

Built 1955 Load: 71.7 t ADT: 11,527

BLAKE HILL ROAD

Good

Over: BLAKE BROOK

0.8 MI FR OLD BRISTOL RD, Belknap, NH

Built 1999 Load: 71.8 t ADT: 142

FEE TPK

Good

Over: BABOOSIC BROOK

2.9 MI FROM BEDFORD T.L., Hillsborough, NH

Built 1954 Load: 71.8 t ADT: 73,393

FRAZIER ROAD

Good

Over: FRAZIER BROOK

.06 MI FR WILMOT T/L, Merrimack, NH

Built 1987 Load: 72.6 t ADT: 82

WELLINGTON ROAD

Good

Over: CONVERSEVILLE BROOK

0.1 MI. RTE.119, Cheshire, NH

Built 2021 Load: 73.1 t ADT: 828

MAIN STREET

Good

Over: CONTOOCOOK RIVER

85 FT FR GRANITE ST, Hillsborough, NH

Built 1940 Load: 73.3 t ADT: 6,029

NH109

Good

Over: NINETEEN MILE BAY

5.0 MI SE MOULTONBORO TL, Carroll, NH

Built 1993 Load: 73.5 t ADT: 2,481

LAWRENCE ROAD

Good

Over: SPICKET RIVER

1.08 MI FR MASS SL, Rockingham, NH

Built 2010 Load: 73.9 t ADT: 6,333

Showing 2,251-2,300 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.