From: To: Subject: Re: Rivers-List: Problems for 21st Century Date: 06 July 2000 00:09 Hello It has been interesting observing the discussion of topics related to eco-hydraulics. The thoughts put forward by Klaus Jorde and Michel LeClerc are right on the mark. It opens up the question of how much "eco" and how much "hydraulics" should be in "eco-hydraulics". The topic: Problems for the 21st Century and the attendant discussions should actually help in better defining eco-hydraulics. In developing the Instream Flow Incremental Methodology, the Instream Flow Group approached the riverine ecosystem problem as a combination of a decisionmaking problem and a problem in assembling and organizing technologies to supply information to decision makers. Note that I did not say the main focus was developing new science, though some of that happened along the way. Similarly, I believe that the Eco-hydraulics Division will evolve it's focus on this class of problems and, of necessity, end up defining some boundaries of pursuit. For example, the life cycle of aquatic organisms is often impacted by human intervention in river systems that may be relatively minor when measured in terms of hydraulic effects per se. Yet, I suspect that life cycles, predator-prey relationships, population dynamics, etc. are likely to be determined to be beyond the pervue of eco-hydraulics. Therefore, I propose that a very useful pursuit and possible topic would be: How to interact with the biological disciplines in terms of identifying major hydrologic/hydraulic processes that need be desribed so those disciplines can do the life cycle, population, etc. work needed to quantify and predict the biological effects of events in the river. Subtopics would be: The kind, resolution, distribution (temporal and areal), and density of information needed. A hierarchy of these items to enable limited resources to be put to best use in studies. A priority scheme indicating urgency of particular items. Terry J. Waddle, Ph.D. Hydrologist U.S. Geological Survey 4512 McMurry Ave. Ft. Collins, CO 80525-3400 U. S. A. Tel: (970) 226-9386 Fax: (970) 226-9230 e-mail: terry_waddle@usgs.gov Internet: http://www.mesc.usgs.gov