FLOOD00310

• County: Arapahoe
• Stream Name: South Platte
• Title: Union Avenue Boat Drop
• Date: 1/1/1983
• Prepared For: CWCB
• Prepared By: CWCB
• Floodplain - Doc Type: Floodplain Report/Masterplan

ABSTRACT

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The Instream Flow Group (lFG) has conducted research into methods
of quantifying instream flow needs for fish, wildlife, and recreation.
This paper describes two techniques developed by IFG for performing
recreational instream flow studies. The single cross section method is
relatively simple and provides a base flow figure which will provide for
the boating activities which make use of the of river. The incremental
method is more sophisticated and may be used to develop recommendations
regardi ng streamflows requi red for vari ous types of recreation, or to
provide a recreation analysis of any streamflow. Streamflow suitability
criteria for recreation are presented for both methods.

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INTRODUCTION

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It has been long recognized that there are many competing demands
for the use of stream water. Diverting stream water for irrigation,
water supply, and energy developments can deplete streamfl ows to the
poi nt where opportuni ti es for recreation and the associ ated envi ron-
mental values of the stream are seriously impaired. Numerous water
planning studies, both basin-wide and project oriented, have emphasized
the need to quantify the amount of water required to support recreation,
fish and wildlife resources, and to maintain aesthetic conditions.

The tools and techniques for estimating streamflows required for
recreation and aesthetics, and for insuring reasonable consideration of
recreation and aesthetics in the allocation of stream water, are cur-
rently undergoing study. lnstream flow requirements and values for
recreat ion, in the past, have often been based on ly upon the amount
required to maintain a fishery. However, several studies have indicated
that recreati on and aesthetic requi rements, at times, may not be the
same as for a fishery.

This paper presents the techniques of assessing instream flows for
recreation. These techniques were developed by the Cooperative Instream
Flow Service Group and closely parallel techniques used to assess
instream flows for fisheries. The data collection procedures, the
physical and hydraulic simulation of the stream, and the computer models
which analyze the data are the same for both fisheries and recreation.
The major difference between the two techniques is the response of the
individual fish or recreationist to various physical parameters of

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