If you're routing commercial vehicles, you need to know which bridges your truck can't clear. The FHWA National Bridge Inventory has 621,000 bridges with height and weight data — but it's buried in an ArcGIS FeatureServer with pagination limits and cryptic field codes.
Road511 normalizes all of it into one queryable API. Plus state-level bridge inventories from PA, OH, TX, VA, NY, FL, WA, and IN with enhanced detail.
The Data
Every bridge record includes:
- Height clearance — vertical clearance in meters
- Weight rating — operating and inventory load ratings in metric tons
- Posting status — open, posted, posted_closed, closed
- Condition ratings — deck, superstructure, substructure (0-9 scale)
- Road carried and feature crossed — "I-80 over Passaic River"
- Year built, ADT, inspection date — for infrastructure analysis
Query by Bounding Box
curl "https://api.road511.com/api/v1/features?type=bridge_clearances&bbox=-75.5,39.5,-74.5,40.5&limit=50" \
-H "X-API-Key: your_key"
Returns every bridge in the Philadelphia metro area with clearance and weight data.
Corridor Search
The killer feature for fleet routing — query all restrictions along a route:
curl "https://api.road511.com/api/v1/truck/corridor?from_lat=41.88&from_lng=-87.63&to_lat=40.71&to_lng=-74.01&buffer_km=5&height=4.2&weight=36" \
-H "X-API-Key: your_key"
This returns every bridge clearance, weight restriction, and truck restriction within 5km of the Chicago-to-NYC corridor that a 4.2m tall, 36-ton truck can't clear. The height and weight parameters filter results to only show conflicts.
GeoJSON for Route Overlays
curl "https://api.road511.com/api/v1/truck/corridor/geojson?from_lat=41.88&from_lng=-87.63&to_lat=40.71&to_lng=-74.01&buffer_km=5" \
-H "X-API-Key: your_key"
Drop the response directly onto a map to visualize every restriction along the corridor.
Data Sources
| Source | Bridges | Coverage |
|---|---|---|
| FHWA NBI | 621,000 | All US states + DC + PR |
| Pennsylvania PennDOT | 56,000 | PA bridges + 3K restricted roads |
| Texas TxDOT | 58,000 | TX posted bridges |
| Ohio ODOT | 45,000 | OH posted bridges |
| Virginia VDOT | 40,000 | VA posted structures |
| New York NYSDOT | 2,300 | NY posted load + height bridges |
| Washington WSDOT | 10,800 | WA bridge inventory |
| Indiana INDOT | 4,400 | IN LiDAR per-lane clearances |
| Florida FDOT | 824 | FL weight-posted bridges |
Who Uses This
- Fleet management software — pre-route clearance checks
- Logistics platforms — automated route validation
- Oversize/overweight permitting — clearance verification
- Engineering firms — infrastructure condition analysis
- Insurance — bridge condition risk scoring
Try It
- Live map — zoom into any area to see bridge markers
- API docs
- Free API key
This article was originally published by DEV Community and written by Roman Kotenko.
Read original article on DEV Community