FLOOD04263

• County: Statewide
• Basin: Statewide
• Title: Design of Open Channels
• Date: 10/1/1977
• Prepared By: USDA Soil Conservation Service
• Floodplain - Doc Type: Educational/Technical/Reference Information

2-4

Approx. e
Photo No. Date Point Line Brg. Length Description
DGB-2E 27 Apr. A <i: rd. at bridge
110 1949 Roanoke Chan.
A-B NE 548'
B N.W.cor.fld.N. of
rd. and E. of Chan.

DGB-2E
112

27 Apr. C
1949

S.W.cor.fld.with N-S
lines, N. of Roanoke
Chan.

C-D

ENE

942'

D

S.E.cor.fld.with N-S
lines, N. of Roanoke
Chan.

DGB-2E-
4S

27 Apr. E
1949

<i: rd.in line wi th
N-S fence W. of barn
about 300' W. of rd.
junc.

E-F

ssw

736'

F

<i: rd.in line with
N-S fence on W. side
of L-shaped fld. S.
of rd.

e

3. Have prepared from these photographs a semicontrolled photo
mosaic of the flood plain to a scale not smaller than 1" = 400'.
A film positive should be prepared of the aerial mosaic on 22" x
30" planprofile sheets with the aerial mosaic as the plan portion
of the sheet. At least two copies of each film positive are suggested-
one for use in preparing a problem location map and profile of
the channel and flood plain, and the other for use in preparing the
location plan and profile of channel improvement. Also, ozalid
prints of each sheet are suggested for use, as working copies by
all planning specialists in planning and evaluating project works
of improvement.

4. In areas for which USGS topographic maps (scale I" = 2000') have
been completed recently by photogrammetric methods, the aerial
mosaic may be semicontrolled to these USGS quadrangle sheets.
In this case, the steps outlined in items 1 and 2 above would not
be needed.

Where semicontrolled photo mosaics are used for horizontal control,
the location of stream channel improvement may be shown on these
mosaics. Other existing maps or plans of equivalent accuracy sometimes
are acceptable for this purpose.

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