FLOOD09355

• County: Mesa
• Community: Grand Junction
• Stream Name: Colorado River
• Basin: Colorado Mainstem
• Title: Colorado River Mapping Project Permanent Control Data
• Date: 5/31/1983
• Prepared For: CWCB
• Prepared By: CWCB
• Floodplain - Doc Type: Data ‎(general)‎

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M E M 0 RAN DUM
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TO:

Randy Seaholm
Senior Water Resources Specialist

FROM:

John A Thorpe, President
Analytical Surv~ys, Inc.

t.a ~ ,1~

DATE:

May 31, 1983

SUBJECT:

Colorado River and Tributaries Mapping Project

1. Raarin9 Fork Floodplain
Study

Vertically, the contours plotted by A.S.I.
tied into the contours from the previous
mappin9 along the roads within 1 0.3 of a foot.
In the open field, the contours varied by 11
foot. Cole Ventures, Inc. (C.V.I.) tied into
control point CH-14RS, used by Air Photo Surveys,
0.03'10w.

Horizontally, these maps didn't tie together.
\~e found that our X values were approximately
600 feet less and the Y values were approximately
200 feet less than A.P.S. grid values on the map.
CVI also tied into cDntrol point CH-14RS and de-
rived a difference in X of 613.00' and in Y,
-228.40'. If the reciprocal scale factor
(1.0003.95), is applied to the cODrdinated of
CH-14RS which APS derived, th~= -1.77' and
ll.Y= -1.81'.

2. Carbondale Colorado

Prepared by Kucera/Schmeuser and Associates,
~lap scale 1"=200', CI=2'.

At the time we mapped this area there were no
existing map ties. We sent Kucera our map edges
and horizontal control information in order that
they could tie into our mapping.

Prepared by Delta Aerial Surveys, November
1980, mapping scale is 1"=200' with a 2' contour
i nterva 1.

3. Glenwood Sorinqs, Colorado

Vertically, we tied into the existing mapping
within a foot. On the southern edge of the
Glenwood Springs mapping, there were some varia-
tions in the contours along the Four Mile
Creek. The reason for this is probably due to
the fact that this area is covered with heavy