Bridges

Looking through ALPR data, I noticed how some ALPR cameras were not positioned in the typical areas. Rather, they were installed near the intersection of roads and rivers. These bridges represent chokepoints in our road network that are harder to avoid (bridges are not often constructed). This wikipedia page lists all the Mississippi river crossings from the Ohio river to the Gulf of Mexico. Excluding ferries there are only 18 crossings over an area of ~800km / ~500miles. Meaning it would take a trivial number of ALPRs to observe all of the interstate traffic. Mississippi aside, the same story is playing out on a smaller scale along other rivers as well.

What are Typical areas?:
In vicinity of off ramps of large roads
nwr[highway=primary_link]({{bbox}});
nwr[highway=secondary_link]({{bbox}});
nwr[highway=motorway_link]({{bbox}});

Hospitals
nwr[amenity=hospital]({{bbox}});
nwr[healthcare=hospital]({{bbox}});

Parks
nwr[leisure=park]({{bbox}});

Shopping Malls
nwr[shop=mall]({{bbox}});

Sports Pitch
nwr[leisure=pitch]({{bbox}});

Warehouses
Police Departments / Correctional Facility
Lowes/Home Depot
Higher density housing (HOA areas/new builds)

The following cameras were detected within 100 meters of a bridge that crossed over a river.

Map
Table

Code

import pandas as pd
import geopandas as gpd
import folium
import itables
from datetime import datetime
bridgegdf = gpd.read_file("../../../osmetc/bridges.gpkg")
bridgegdf.explore(style_kwds={"opacity":0.8,"weight":6})

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Code

itables.show(pd.DataFrame(bridgegdf.drop(["geometry"], axis=1)), maxBytes=200000, allow_html=True)

Loading ITables v2.7.3 from the internet... (need help?)

Started with 2,142 datapoints on 2026-05-05. Last updated: 2026-05-05