Earth Support Corp

Cheshire CountyNew Hampshire

Walpole, New Hampshire

Bedrock sits a median 14 ft down across 164 logs, shallower than the New Hampshire median of 20 ft. 1 high-hazard dam is rated in poor or unsatisfactory condition.

Median depth to bedrock

14 ft

middle half 6–51 ft · 164 logs

Bridges rated poor

2

of 16 inventoried · 2 closed

Poor high-hazard dams

1

National Inventory of Dams

FEMA repair $, Cheshire County

$23.3M

federal share since 2010 · county-wide

01 · Ground

Rock is close to the surface: 42% of logs hit it within 10 ft

From 164 depth-to-rock records inside Walpole (NH DES well inventory). Logs cluster where people drill wells and bore for roads, so treat this as the town’s pattern, not a site answer.

Half of Walpole's logs reach rock between 6 and 51 ft

Depth to bedrock: 10th–90th percentile whisker, middle-half box, median tick; dashed line = New Hampshire median.
median 14 ft
NH 20 ft
0255075 ft
0102030400–5 ft5–10 ft10–20 ft20–50 ft50–100 ft100+ ft
n = 164 logsSource: NH DES well inventory
▸ Show the numbers
Depth to rock (ft)Logs
0–532
5–1032
10–2032
20–5026
50–10032
100+10

Rock within 10 ft

42%

of logs (31% across New Hampshire). Shallow rock means ledge in excavations, refusal for driven piles and rock anchors rather than soil nails; deep ground means taller shoring and more groundwater. 25% of logs here go past 50 ft.

02 · Dams & disasters

1 high-hazard dam needs work

FEMA Public Assistance is reported by county, so the figure below is Cheshire County-wide context, not a Walpole number.
High-hazard dams in poor condition in Walpole
DamConditionBuilt
Walpole Reservoir DamPoor1842

High hazard potential means failure would probably cost lives — it rates the consequences, not the dam’s condition.

FEMA Public Assistance, Cheshire County

$23.3M

Federal share obligated across 218 projects in 9 declared disasters since 2010. The largest category is emergency protective measures (66%); roads & bridges took $7.6M.
Dams, disasters & moving ground

03 · Bridges

2 of 16 bridges are rated poor — above the New Hampshire rate of 8%

Every highway bridge and large culvert in the 2025 National Bridge Inventory that stands inside Walpole. Median age 66 years; 2 closed.

44% good, 13% poor

FHWA good / fair / poor rating — the lowest of deck, superstructure, substructure or culvert.
  • Good7 · 44%
  • Fair7 · 44%
  • Poor2 · 13%

Structures by decade built

01231910s1930s1950s1960s1980s2000s2010s
n = 16 structuresSource: FHWA National Bridge Inventory 2025
▸ Show the numbers
BuiltStructures
1910s3
1930s2
1950s2
1960s3
1980s3
2000s2
2010s1

The poor-rated bridges

Bridges rated poor in Walpole
CarriesOverBuiltDaily traffic
BRIDGE STREETclosedCONNECTICUT RIVER19306,100
BRIDGE STREETclosedCONNECTICUT RIVER19300
Every poor bridge in New England

04 · Next door

Walpole and the 8 towns that border it

A dash means no data for that layer, not zero.
Walpole compared with neighbouring towns
TownPoor bridgesRock depth
Walpole, NH2 / 1614 ft
Rockingham, VT5 / 2227 ft
Westmoreland, NH2 / 1824 ft
Putney, VT2 / 1617 ft
Charlestown, NH1 / 1321 ft
Westminster, VT0 / 1215 ft
Alstead, NH1 / 720 ft
Langdon, NH0 / 522 ft
Surry, NH0 / 417 ft

Where these numbers come from

Method, sources & caveats

Walpole is the Census county subdivision 3300578420 (Cheshire County). Every record is placed here by its coordinates, not by the place name the source uses.

  • Towns are Census county subdivisions: cities, towns, plantations, and Maine/New Hampshire unorganized territories and townships. Every record is placed in a town by its coordinates (point-in-polygon), not by the source's own place label — so a bridge in Roxbury counts for Boston and a well in 'North Waltham' counts for Waltham.
  • Bridges: FHWA NBI 2025, highway structures ≥ 20 ft including large culverts. 'Poor' is FHWA's good/fair/poor rating (lowest of deck, superstructure, substructure or culvert ≤ 4). Percent-poor is shown only for towns with at least 5 structures.
  • Depth to bedrock is the median of driller- and boring-reported depths in the town, shown only where at least 10 logs exist. Water-well logs over-sample rural lots and hilltops; one town median never describes a particular site.
  • Bedrock depths use the same state databases and filters as the Bedrock & soils module (bedrock wells and borings that reached rock, 0 < depth ≤ 400 ft, exact re-filings dropped), but every log is placed in a town by its coordinates rather than the driller's town field, so town counts can differ slightly between the two pages. Connecticut and Rhode Island have no statewide public well-log database with depths.
  • Dams: only high-hazard-potential dams whose latest condition assessment is Poor or Unsatisfactory are counted (live NID). Connecticut and Rhode Island assessments may lag.
  • FEMA Public Assistance dollars are federal share obligated for disasters declared since 2010, reported by county — they are county context, not a town figure.
  • Grant awards are Massachusetts only (EEA Dam & Seawall program, MVP Action grants, CZM Coastal Resilience). Other states' programs are not yet included.
  • Ground-related permit counts cover only the municipal portals the pipeline reads (Boston, Cambridge, Somerville, Worcester, Framingham, Providence, Portsmouth, Hartford and a few others) — an absent count means 'not covered', not zero.
Data as of
Sep 11, 2026
Generated
Sep 11, 2026
Records
367,748
Refresh
Live pull · weekly

Published by Earth Support Corp as a public resource. Regional statistics for planning and curiosity. They are not an engineering report, a bid recommendation or a statement about any particular site, firm or project. Spot an error? Tell us and we will correct it. Full method: methodology.

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