Differences of Trails between US Topo PDF, FSTopo PDF and FSTopo vector data

roblabs commented 6 years ago

Summary

GeoPDF and Vector Shape file data for 7.5' Palomar Observatory quad show there are differences between the USGS and USFS topo maps.

Filing this issue as a tracking issue to share with others who may be using the US Topo PDF, FSTopo PDF and FSTopo vector data.

See live map at RobLabs.com/usgs

Issues

[ ] Is there any documentation on the FCSUBTYPE? An issue filed by JesseCrocker suggests that FCSUBTYPE = 107 & FCSUBTYPE = 525 are significant: https://github.com/JesseCrocker/USFSTrailImport/issues/1
[ ] Entirely possible that the next revision of US Topo for Palomar Mountain (and others) will have the update.
[ ] Is it possible that the the USGS vector data is sourced from the FSTopo Transportation Line and are mis-categorized in the FSTopo vector data set?

Observations

USFS legend shows roads near Barker Valley trailhead as "Unimproved, 4 wheel drive"
USGS legend shows roads near Barker Valley trailhead as "Local Road", but it does have a legend option for "4WD"
- USGS does not show the Barker Valley trail
- USFS Vector file, FSTopo Transportation Line (Date of last refresh: Oct 25, 2017) shows the Barker Valley trail labeled as FCSUBTYPE = 107
- FSTopo Transportation Line Source

QGIS view of `FSTopo Transportation Line`, `FCSUBTYPE = 107`

QGIS view of `FSTopo Transportation Line`, `FCSUBTYPE = 106`

Barker Valley trail is just below this highlighted section of the Palomar Divide Road.

FSTopo `PALOMAR OBSERVATORY, CA`

This product generated and downloaded on 2/2/2017
wget https://data.fs.usda.gov/geodata/rastergateway/data/33116/fstopo/331511645_Palomar_Observatory_FSTopo.pdf

US Topo `PALOMAR OBSERVATORY, CA`

Modification date from PDF proprieties — Mar 28, 2016, 8:40 AM
wget https://prd-tnm.s3.amazonaws.com/StagedProducts/Maps/USTopo/1/22340/7541782.pdf

usgs-palomar-observatory

roblabs commented 6 years ago

Barker Valley Trailhead is near (-116.7884, 33.3399).

US Topo is Palomar Observatory, CA.

I also see on the The National Map basic download that the trail shows in these tiles.

Is it possible that the issue is solely with the US Topo of Palomar Observatory, CA from 2015?

roblabs commented 6 years ago

This particular trail, Barker Valley, is out of sync in the USGS US Topo for the following reason,

Regarding Barker Valley Trail. The data we received from USFS called this a trail. The reason the trail does not show up on US Topo is that the trail was loaded to our database on 4/28/17 which is after the US Topo map was published.

See the USGS planned production schedule for more details. The image below is directly linked to the USGS page below.

https://www.usgs.gov/media/images/planned-us-topo-map-production-schedule-next-three-year-revision-cycle

roblabs / gdal-geopdf