NOTICE: help.openstreetmap.org is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum

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's gravatar image

mccarbc
31446
accept rate: 0%


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:

  1. To see if the waterway is considered big enough to map (I also look at available aerial imagery). There are lots of dry gullies around here that may have a visible ephemeral water course that carries so little water so rarely that it is debatable if it counts or not. But if the USGS thought it counted then I figure that is an indication that OSM might be interested in it.

  2. To see if the waterway has a name.

  3. To roughly draw the waterway in.

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.

permanent link

answered 20 Aug '21, 16:30

n76's gravatar image

n76
10.8k1082172
accept rate: 17%

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 ♦
Your answer
toggle preview

Follow this question

By Email:

Once you sign in you will be able to subscribe for any updates here

By RSS:

Answers

Answers and Comments

Markdown Basics

  • *italic* or _italic_
  • **bold** or __bold__
  • link:[text](http://url.com/ "title")
  • image?![alt text](/path/img.jpg "title")
  • numbered list: 1. Foo 2. Bar
  • to add a line break simply add two spaces to where you would like the new line to be.
  • basic HTML tags are also supported

Question tags:

×18
×8
×3
×2

question asked: 20 Aug '21, 15:54

question was seen: 823 times

last updated: 21 Aug '21, 11:20

NOTICE: help.openstreetmap.org is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum