Research by Jack Parsell, author of lowpoint book

The legendary Jack Parsell sent me the following email after I sent him the recent posts regarding the new lowpoint of Colorado. - John Mitchler

John

Thanks for sending the latest input on the CO low point. Also I really like the topo map
site, Topozone. I spent a lot of time yesterday checking all three of the rivers. Here is
what I found:

Arkansas River at the CO-KS line: N38.030, W102.045; map scale 1:25000.
The 3350 ft. contour crosses the river 0.45 mile into CO.
The 3340 ft. contour crosses the river 0.9 mile into KS.
By interpolation, and assuming uniform gradient in the river bed, elevation at the
border is estimated at 3347 ft. Same location with the 1:100000 map lists actual
elevation at the border 1020 meters which converts to 3346 ft. Good agreement.

North Branch Republican River at the CO-NE line: N40.070, W102.052; 1:25000 map.
The 3340 ft. contour crosses the river 1/4 mile into CO.
The 3330 ft. contour crosses the river 1 mile into NE.
Again on the 1:25000 map this gives an estimated elevation at the border of 3338 ft.
On the 1:100000 map it comes out to 1017 meters or 3337 feet. That makes the
Republican 9 ft. lower than the Arkansas.

Arikaree River at the CO-KS kine: N39.978, W102.052; map scale 1:25000.
The 3320 contour crosses the river 1/4 mile into CO.
The 3310 contour crosses the river 3/8 mile into KS.
On the 1:25000 map this gives an estimated elevation at the border of 3316 feet.
On the 1:100000 map the 1010 meter contour crosses the river just into Ks about
0.1 mile. Estimate at the border is 1010.07 meters which eqals 3314 feet. So the
Arikaree is definitely the lowest if the maps are accurate.

When I get a chance I'll write to the US Geologic Survey to see if they will look into this.

Regarding the others who are interested in this,
"bob" mentioned using a GPS to check the elevations. Unfortunately a hand held GPS
does not give very accurate elevations. If we were loking at differences of 100 feet then
the GPS might be helpful. However, I just heard that President Clinton signed a bill
removing the selective availability from civilian use of GPS devices. This was effective
as of 8 PM EDT on May 1. This will improve position location but probably won't help
much on elevation.

When Joyce & I, together with Clark Hall, went to the CO-NE-KS tristate corner we crossed
the Aricaree and when we hit the CO-KS line we were only 1/2 mile north of the low point.
The tripoint is about 3 1/2 miles N of the low point. Now we'll have to go out there again.
Looks like another fun project !

Jack