Southeastern Connecticut Planning RegionConnecticut
Griswold, Connecticut
2 of its 25 inventoried bridges are rated poor (8%, against 5% statewide).
- Live · as of Sep 11, 2026
- 9 public sources · method
- ← All towns
Bridges rated poor
2
of 25 inventoried
01 · Bridges
2 of 25 bridges are rated poor — above the Connecticut rate of 5%
Every highway bridge and large culvert in the 2025 National Bridge Inventory that stands inside Griswold. Median age 68 years; 1 posted for weight.
28% good, 8% poor
FHWA good / fair / poor rating — the lowest of deck, superstructure, substructure or culvert.
- Good7 · 28%
- Fair16 · 64%
- Poor2 · 8%
Structures by decade built
n = 25 structuresSource: FHWA National Bridge Inventory 2025
▸ Show the numbers▾ Hide the numbers
| Built | Structures |
|---|---|
| 1930s | 4 |
| 1940s | 2 |
| 1950s | 11 |
| 1980s | 1 |
| 1990s | 1 |
| 2010s | 5 |
| 2020s | 1 |
The poor-rated bridges
| Carries | Over | Built | Daily traffic |
|---|---|---|---|
| INTERSTATE-395 | BISHOP CROSSING RD | 1958 | 34,800 |
| TAYLOR HILL ROAD | INTERSTATE-395 | 1958 | 645 |
02 · Next door
Griswold and the 6 towns that border it
A dash means no data for that layer, not zero.
| Town | Poor bridges |
|---|---|
| Griswold, CT | 2 / 25 |
| Plainfield, CT | 1 / 29 |
| North Stonington, CT | 0 / 23 |
| Canterbury, CT | 3 / 13 |
| Preston, CT | 0 / 9 |
| Lisbon, CT | 0 / 6 |
| Voluntown, CT | 1 / 4 |
Where these numbers come from
Method, sources & caveats
Griswold is the Census county subdivision 0918033900 (Southeastern Connecticut Planning Region). 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
- U.S. Census Bureau cartographic boundary files — county subdivisions (2024, 1:500k)Public domain
- FHWA National Bridge Inventory (2025 delimited files)Public domain
- USACE National Inventory of DamsPublic domainHigh-hazard dams rated Poor or Unsatisfactory (live NID).
- USGS U.S. Landslide InventoryPublic domain
- MassGIS / Massachusetts Geological Survey — Bedrock Data PointsPublic recordBorings and well logs that reached rock (MassDEP well drillers, USGS, MWRA, MassDOT…); seismic/HVSR and map-derived shallow-bedrock/outcrop points excluded.
- NH DES Water Well Inventory, Maine Geological Survey Wells Database, Vermont DEC well recordsPublic recordBedrock wells only; driller-reported depth to bedrock / overburden thickness.
- OpenFEMA Public Assistance Funded Projects Details (v2)Public domain
- MA EEA / CZM grant awards — Dam & Seawall, MVP Action, CZM Coastal ResiliencePublic record
- Municipal open-data permit portals (Boston, Cambridge, Somerville, Providence, Portsmouth, others)Public recordOnly permits flagged as ground-related (retaining walls, excavation, foundations) are counted.
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.