Topo Map Contour Interval

[maps4gps]

Does anyone have or know where to get a list of the contour intervals used on each of the USGS 24k topo maps?  I remember a file on one of the USGS servers about 10 years ago, but their 'ask a question' sites are saying such a file/list does not exist.  Thanks.

[maps4gps]

That site is easier to use than the USGS site, however, with over 54,000 quads it still is not feasable.

[-Oz-]

It would be useful.  I just check a few spots and go with the smallest (thus why mississippi was 5ft and AZ 40ft.)

I'll email you back this evening.

[-Oz-]

10', that is interesting... thats cuz eastern oregon is surprisingly super flat.

In Idaho I actually did most at 40' and a few at 30'

[Boyd]

For my map of South Jersey I used a 5' contour interval. Around here we have Forked River "Mountain" with a dizzying summit of some 200 feet  (actually the view is pretty impressive from there). The 5' interval reveals a lot about the terrain as opposed to the Garmin maps which have very few contour lines showing. Personally I think you need to fine tune this to the terrain to acheive the best results and make your map more distinctive.

[maps4gps]

... I think you need to fine tune this to the terrain to acheive the best results and make your map more distinctive.

I agree.  That is what I am trying to do.   I was using the CI on the 100K, dividing by 4, and converting to feet; but that does not give the usual foot intervals (40,20,10,5,2), so I adjust by visual inspection.  But I keep second guessing; and going more detailed than the 24K the NED/DEM was produced from is probably invalid. 

[-Oz-]

i wonder how they did the 100k; it has to be some ratio or something along those lines.

[maps4gps]

They were 'panneled' from the 24Ks; which were pushed through as provisional versions so the 100Ks could be completed.

[maps4gps]

It would be useful.  I just check a few spots and go with the smallest (thus why mississippi was 5ft and AZ 40ft.)

I'll email you back this evening.

Dan,  If you were going to email me, I have not received anything. Mark

[maps4gps]

Have not found one yet.