FLOOD06672

• County: Logan
• Community: Crook
• Stream Name: South Platte River
• Basin: South Platte
• Title: South Platte River at Crook
• Date: 10/1/1993
• Prepared For: Crook
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Floodplain Report/Masterplan

foot. The en1:iire staff is then painted wi't:h white enamel.
The scaled groove!1 are painted with black, enamel. The stage
readings are pcdnt,~d, on the white background w:.th black enamel,
using a stencil to aid in making the humerals uniform.
Commercially mcldel lataff gages can be purcha,sed from a number of
vendors. Two ve,ndors that have provided staff gages in the
past are:

Leupold & Stevelns, Inc.
P.O. Box 688
Beaverton, OR 9707!i,
(503-646-9171)

science Associates, Inc.
P.O. Box 230
Princeton, NJ 08542
(800-247-7234)

4.1.2 site Installation Information
Both the lli~rh'way 6 bridge at Sterlin9: and the Highway 55
bridge at Crook have, concrete piers. Most bridge engineers
discourage drilling into reinforced concrE'te bridge piers and
it is likely tbat, permission would not be 'Jiveln to ,mount staff
gages on the downstream side of the piers.

Because of thE~ bridge configuration, 1::he staff gages will
likely have tel be mounted on specUllly constructed
installations nelc't 1:0 the river. A wood~n or I-beam piling
driven next to the hank would provide a st.tble location for a
staff gage. Staff gages should be built: on the downstream
river bank, out of the path of floating deb:t:'is" They will have
to be located el.)se enough to the water to provide the stage
range necessary for flood warning, and mus,~ be located in, or
close to, the ,;h.mnel cross section downst:ream of the bridge
for which the gag'e ~'i'lting curve was developl~.

Another option would be to paint the sti'lff gage numbers
and marks directly onto the concrete piers. ,This would require
fr.equent re-paint:ingr, as necelSsary, so tha t the stage heights
can be easily read.

4,2 Automated sti'lge Detection
4 . 2 . 1 Backgrou:nd
The flood de,t,ec:t.ion device presented in this report was
developed by the U.S. Army Corps of Enginee,rs, Omaha District,
in 1989. The d,evices are curt'ently in use 'in 3 flood warning
systems located in NebraSka, Iowa and South Dakota. Systems of
this type has been proposed for Wiggins, Colorado and suburban
areas near Na!'hville, TennelSsee. An ov~rview of a flood
warning gage as it could be installed on the north downstream
bank of the North Cllannel of the South Plat1:!;! River at Sterling
is shown in Figu,rfe 4. Other flood deteo:;'t;i"n equipment is
available commercially, but it is gea~ed toward larger
communities with :Large annual budgets.

4.2.2 Description 01: Flood Detection Gage
The flood alarm consists of an Adem:~o 612 Tape Dialer
Alarm mounted in an instrument shelter. At Sterling, the
instrument sl1e11:er could be separated from t,l1e stilling well,

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