Laserfiche WebLink
<br />. <br /> <br />. <br /> <br />. <br /> <br />. <br />r <br /> <br />, . <br /> <br />INTRODUCTION <br /> <br />The purpose of this report is to provide a recommended procedure to determine the amount of <br />streamflow in the East River at a location immediately downstream from Crested Butte Mountain <br />Resort's (CBMR) snowmaking diversion, Monitoring of East River streamflow is a condition of <br />CBMR's special use permit with the U.S. Forest Service, <br /> <br />BACKGROUND <br />In 1981 C8MR made application to the U,S. Forest Service for amendment of its special use permit <br />to allow the development and operation of a snowmaking system, By Agreement dated June 25, <br />1981, CBMR received permission to proceed to construct the system provided certain terms and <br />conditions were implemented, One of the conditions required CBMR to install a streamflow <br />monitoring station on the. East River downstream of the snowmaking diversion. The station was <br />to monitor streamflow on a continuous basis for the period October 1 st through April 30th of each <br />year, <br /> <br />In response to the monitoring condition, CBMR constructed a streamgage station on the East River, <br />The station consisted of water stage manometers designed to measure the pressure (weight) of <br />water over a pressure sensitive orifice submerged on the bottom of the river, Generally, the deeper <br />the water in the river, the greater the pressure over the orifice. The pressure differences were <br />converted to stream depth (stage) and ultimately to streamflow through the use of a water <br />stagefdischarge rating curve developed for the site. The rating curve was developed by making <br />several field measurements of streamflows at various water depths, <br /> <br />Immediately after installation of the pressure gage, CBMR began experiencing difficulty with <br />obtaining accurate and reliab!e rllc;qrdl!,.. TI}.e !emote _'oc;~~i9n..Jl.!!.d e~re.!"ely c_otd..1el1lJl.e!at!Jr~s . <br />combined to create maintenance and logistic problems, In addition, the occupance of winter ice <br />and snow cover over the East River prevented winter monitoring. The ice affected the depth of <br />water and corresponding pressure differential over the submerged orifice, As a result, the <br />stagefdischarge relationship established for the site was not accurate during the winter period. <br />Due to these difficulties, C8MR was forced to abandon the East River monitoring station and <br />implement alternative streamgaging procedures. <br /> <br />1 <br />