Listed on the National Register of Historic Places in 1981. 6 historic topographic surveys show this location, the earliest from 1921.
From the record
“The Lower Blackburn Grade Bridge, also named the Van Duzen River Bridge or Mile 18 Bridge, is a 258-foot-long (79 m) reinforced concrete through arch with a main span approximately 150 feet (46 m) over the Van Duzen River about 4 miles (6.4 km) west of Bridgeville, California, United States. It was active from its construction in 1925 to 1985 when replaced.”
Wikipedia article Lower Blackburn Grade Bridge, CC BY-SA 4.0.
One of 52 National Register listings published here for Humboldt County · listed in 1981 · category: Structure.
National Register reference number.81000148- the number the National Park Service assigned this property when it was listed, and the key its nomination file is catalogued under at the National Archives.
Then and now
1921 to 1979
The ground this property stands on, surveyed
58 years apart. Drag the handle to wipe between them. Both sheets are
United States Geological Survey originals; neither has been altered.
19211979
Fires near this property
98 since 1992
Regional context, not property-specific
evidence. The
federal wildfire occurrence database
lists 98 fires within 5 miles of Lower Blackburn Grade Bridge
between 1992 and 2020, burning about 346 acres in total. 6 started naturally. 6 were recorded as arson.
Distance is straight-line from the map coordinates, so a fire counted
here may appear on a neighbouring settlement's page as well.
Reported cause
Fires
Equipment and vehicle use
22
Missing data/not specified/undetermined
22
Power generation/transmission/distribution
19
Debris and open burning
16
Natural
6
Arson/incendiarism
6
Smoking
4
Recreation and ceremony
2
Misuse of fire by a minor
1
The most recent of
them, most recent first, with the day each was reported and the service
that recorded it.
Date
Cause
Size
Reported by
Name on the report
8 September 2011
Smoking
under an acre
Humboldt-Del Norte Unit
BRIDGEVILLE
8 September 2009
Missing data/not specified/undetermined
under an acre
Humboldt-Del Norte Unit
HWY 36 BRIDGEVILLE
5 September 2014
Missing data/not specified/undetermined
24 acres
Humboldt-Del Norte Unit
HOUSE
4 September 1992
Arson/incendiarism
under an acre
Humboldt-Del Norte Unit
VAN DUZEN #1
4 September 1992
Arson/incendiarism
under an acre
Humboldt-Del Norte Unit
VAN DUZEN #3
4 September 1992
Arson/incendiarism
under an acre
Humboldt-Del Norte Unit
VAN DUZEN #2
4 September 1992
Arson/incendiarism
under an acre
Humboldt-Del Norte Unit
VAN DUZEN #4
3 September 2016
Missing data/not specified/undetermined
under an acre
California Department of Forestry & Fire Protection
Regional context, not property-specific
evidence. The federal mineral resources record lists
3 workings within 5 miles of Lower Blackburn Grade Bridge: 3 producers.
All of them still produce. What was taken out: Sand and Gravel, Construction, Stone, Crushed/Broken. Distance is straight-line from the
map coordinates, so a quarry counted here may appear on a neighbouring
settlement's page as well.
Regional context, not property-specific
evidence. The National Weather Service names
Bridgeville, the town this property stands in, in 5 storm reports between 1997 and 2025: 4 heavy rain, 1 funnel cloud.
No death or injury is recorded in these reports. Each account below is quoted exactly as the forecast office
filed it, from the NOAA Storm Events Database, and each date
opens the federal record of that event.
Multiple slipouts and sinks along Highway 36 from mile post 3 to 44 due to heavy rain during the month of January and early February. All damage along this section of highway was compiled into one report and given a January 24th event date.
United States Geological Survey topographic
sheets whose coverage includes this point. Matched by taking the coordinate the National Park Service records for this property, then
testing that coordinate against the published boundary of every sheet.
Listing record. National Park Service National Register of Historic Places, listed-properties dataset, current to 2026-05-22.
Map join. Address geocoded through the United States Census geocoder, then tested against the published boundary of every sheet in the USGS Historical Topographic Map Collection.
How this page is made. Listing fields come from federal records; map-sheet coverage is a labelled coordinate-to-boundary calculation, not a source-field claim.
Wildfire. Short, Karen C. 2022. Spatial wildfire occurrence data for the United States, 1992-2020 [FPA_FOD_20221014]. 6th Edition. Fort Collins, CO: Forest Service Research Data Archive. https://doi.org/10.2737/RDS-2013-0009.6 Collected with United States Government funding and usable without additional permissions or fees.
Mines and quarries. USGS Mineral Resources Data System (MRDS) https://mrdata.usgs.gov/mrds/ A work of the United States government, no copyright under 17 U.S.C. 105.
Storms. NOAA National Centers for Environmental Information, Storm Events Database https://www.ncei.noaa.gov/stormevents/ A work of the United States government, no copyright under 17 U.S.C. 105. Narratives are quoted verbatim from the National Weather Service report and are not edited or summarised.
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