WSP09117

• File Number: 8102
• Description: Arkansas River Hydrology
• State: CO
• Basin: Arkansas
• Water Division: 2
• Date: 10/1/1970
• Author: Colorado DNR
• Title: Preliminary Report on Travel Time and Transit Losses Arkansas River October 1970
• Water Supply Pro - Doc Type: Report/Study

OJJ218

SECTION VI

SUMMARY AND CONCLUSIONS

A preliminary determination of travel time and transit losses for reservoir
releases on the Arkansas River from Twin lakes to the Colorado Canal, a distance
of some 162 mi les, has been made. The basis for the work under an agreement dated
June 10, 1970, with the State of Colorado has been:

a. Review of past studies on the Arkansas River.

b. New research conducted since early spring, 1970.

c. The detailed field and office study of the Twin Lakes Reservoir release
beginning on May 2, 1970.

d. Study of and visits to all of the state-operated and U.S. Geological
Survey-operated gaging stations above Nepesta.

e. Extensive field inspections of the river.

f. A review of some 30 reservoir runs made between 1966 and 1970, uti lizing
original stage-time curves.

g. Office studies, additional literature review, and computations.

h. Interviews with individuals involved in river administration.

The travel time relationships for reservoir runs on the Arkansas River have
been developed and presented in detail In the report. A nomograph has been de-
veloped for administrative use. In addition, rates of openings and closings for
the Colorado Canal headgate have been included as a guide for efficient diver-
sions of reservoir runs. We have concluded that for most reservoir runs the
accuracy of the travel time nomograph is within two hours for the range of re-
leases presented. It is pointed out in the report that with large discharges
where overbank flow occurs the nomograph is .not applicable.

Revised travel time estimations must be made in the future if and when the
hydraulic and flow regime of the river changes. The regime can be changed in
many ways, such as: the construction of the Puebio Dam, channelization by the
Corps of Engineers, sustained large flows by the Fryingpan-Arkansas Project, and
so forth.

The transit loss studies took into consideration some two Jozen factors..
Using the most significant factors, methodology has been developed and presented
for application of appropriate losses to reservoir runs based upon three main
categories of losses. These categories are evaporation, bank storage, and un-
authorized diversions. The background Information, method of computation, and
preliminary results are given in the report along with a suggested form for use
by administrative officials for computing the losses for each reservoir run.

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