Recreational Instream Flow Workshop Tanscription of Meeting Tape

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Unidentified Speaker You have river bed there that obviously if it has been channelized then it's narrower but if it's still more or less the river bed as nature made it and now our questions is how much water needs to flowing down it for adequate white water boating with these kind of structures then don't we need to have some sort of feel for how that relates to what would otherwise be in that river? Glenn Porzak The question if I might interpose, the question presupposes that you are not controlling or diverting the water and that it's somehow in natural state and that just not ...the foundation or basis of your question is not accurate. Unidentified speaker Then let me rephrase it. O.K. Assuming that you are controlling and diverting some of the water but there is still. You know, this white water boating is not entirely a man made concept. There is obviously some relation to what water was flowing down that bed in the first place. So, even if you are diverting 90% of it the questions still becomes how is a minimal stream flow for white water boating how does that compare to the natural flow, that would be flowing down that river in approximately the year 1850. Glen Porzak That's on the design capacity of the given course Unidentified Speaker That is what I am asking. Gary Lacy I think there is a real easy answer and that is pick a natural river and of course they have high and low flows and rivers change naturally there are narrower and wider so I guess if you are going down, say pick a natural river and any flow rate and you come to an area where there is natural say cliffs that come and naturally constrict the channel and even have a drop right there and its a natural rapid, that's kind of what I look at. So the very same river at the very same flow at another area where the river is spread out that you may not be able to even float a boat. So it's a tough thing to answer. But I guess the other short thing is that in a particular area that a say a town wants to have one of these. Is to design it so it has water in it that extends the life of the boating season more than previously before this project was built. Greg Walcher - I think what you are saying is that you can design additions to the river that make it more attractive to floaters in various different sizes of rivers depending on how much flow is there right? Gary Lacy Correct. Greg Walcher So doesn't that sort of imply that you also could design recreational enhancements to a river regardless of how much water is being diverted or used in some other capacity somewhere else ... in other words without creating a conflict with existing water users upstream you still can enhance the recreational value of a river... I am trying to figure if the question sort of suggested that there is an automatic built in conflict and I am wondering if it isn't possible to design recreational enhancements that don't necessarily create conflict just based on how much water is there. Gary Lacy You know I guess I would be careful with that one I think there is what I call an adequate even a minimum amount of flow that's required regardless of what «ve can try to build there and you need that water and I don't know where it comes from, if it comes from a reservoir release or its already being released naturally or its just runoff or whatever it is. But at that structure there's a certain amount of water that you need to make these things work and it does vary on the design and everything and so when Golden wants a whitewater park and we look the flow and pick a good flow that makes these work that's what they are designed for and it varies in different locations. 0