Recreational Instream Flow Workshop Tanscription of Meeting Tape

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S Gary Lacy The question was a little more detail on quantifying the amount of flow and how you determine that and a couple of things. One it's obviously dependent on the situation and the location. Boulder Creek is not the South Platte River and Gore Creek is not the Eagle River and so it has to do with the size of that river, and of course the watershed and the amount of water available, but also the design of the structures themselves. And the narrower they are and the more gradient or specific drop at each structure- -the less amount of water they take. The bigger the river the less amount of drop is required and they can be wider. The Colorado River in Grand Junction, having something there, would not, I mean its a huge river but it doesn't take that much drop... something in Gore Creek or Boulder Creek is a lot narrower. So it depends on the specific instance.... but if you look around at some paddlers here they know at various creeks at various flows when you check the flow- phone or the internet you know about what flow is the minimum that really makes these features stand up and create good white water paddling. Eric Wilkinson When you engineer the courses do you design them at a certain rate of flow, or do you know what that is when you design them, what the minimum flow is. Gary Lacy It's the flow rate, so in cubic feet per second - -you look at the hydrograph and look at the months and try to pick numbers that, there is, be careful the nomenclature but what a minimum would be that really would make these structures work and try to obviously maximize the amount of days that would be at that particular area. Dqn Schwindt Do you have some sense of cost per feature or per yard or several yards is on the river or stream or whatever? Gary Lacy Ah , sure. I mean, just per structure in the stream the size of Clear Creek, Gore Creek, ?boulder Creek are all fifty to eighty feet wide plus or minus and each structure varies from about $14,000 to $21,000 dollars per structure to build them. And then if you go to Vail where you got get the nice colored rocks and you pick them up and set them here and turn them certain ways and make sure all the people are happy, its probably two or three times that. Or then Farmington, where the City jumped in the lccal mine donated all the rock and everyone helped out its should of - -on the Animas River which is a much bigger river, should have been there were two drops, about 150,000 dollars each for the bid costs. In reality, with all the donations it ended up being 30,000 dollars each. So that's kind of a range in there. Don Schwindt The bid cost was how much in Farmington? Gary Lacy It was about 150,000 per structure but in reality it was less than a third of that was the actual cost. The main cost factor is the volume of material. And the bigger rivers cost a lot more. The other one that worked with the Water Conservation Board that was very generous and provided the funding was on the Union Avenue Dam project. It was built a number of years ago after a double fatality over a fourteen - foot high dam. A lot of material was put into those structures to step the water down to drop pool features. From the tape log it appears to be a river outfitters rep. Tom Meinschwitz Unidentified speaker I wonder if there, it would have to be very approximate, but is any way to compare the flow required for adequate use of these kinds of facilities as opposed to the natural flow of that stream in different months of the year. Are we talking half of the natural flow or three quarters or a third? Is there any feel for how the adequate flow to optimize most of these white water parks compares to what that stream would be flowing? What that streambed originally carried in its primitive state. Patty Wells Is that what you mean by natural flow without any diversions? Is that what you mean?