I'd like to map some streams in my area and I'm looking for best practices. They're not accessible to track using GPS so I was going to use imagery to map them. The streams are visible on some of the Bing Aerial imagery but not always, but the USGS Topographic maps are very accurate. Is it considered "ok" to use the Topo imagery to trace the streams? Are there best practices with regard to doing so? asked 20 Aug '21, 15:54 mccarbc |
USGS topographic maps are okay to use as a source (that type of US government publication is public domain). In my semi-arid area I use the USGS maps (selected in the JOSM "imagery" pulldown) for three things when mapping waterways:
I find that the USGS topo imagery layer in JOSM (which uses the older maps) to have a fair number of errors in location. So once I get the waterway drawn in per the USGS topos I then adjust it based on imagery to get a better location. answered 20 Aug '21, 16:30 n76 Thanks, your answer was very helpful. I plan to do as you mentioned, first map using the USGS Topo layer then adjust using the Bing imagery.
(20 Aug '21, 18:01)
mccarbc
I think the big thing to be aware of with USGS topos (as with NHD data) is that sometimes the survey data is quite a way in the past, but as an aid in conjunction with recent imagery they are invaluable.
(21 Aug '21, 11:20)
SK53 ♦
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