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<br />REGULATED RIVERS: RESEARCH & MANAGEMENT, VOL. 12,391-413 (1996)
<br />
<br />A GENERAL PROTOCOL FOR RESTORATION OF
<br />REGULATED RIVERS
<br />
<br />JACK A. STANFORD
<br />
<br />Flathead Lake Biological Station, The University of Montana, Polson, MT 59860, USA
<br />J. V. WARD
<br />
<br />Department of Limnology, EA W AG/ETH, Uberlandstrasse 133, CH-8600 DubendorJ. Switzerland
<br />WILLIAM J. LlSS
<br />
<br />Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR 97331, USA
<br />CHRISTOPHER A. FRISSELL
<br />
<br />Flathead Lake Biological Station, The University of Montana, Polson, MT 59860, USA
<br />RICHARD N. WILLIAMS
<br />510 Clear Creek Drive, Meridian, ID 83642, USA
<br />JAMES A. LlCHATOWICH
<br />182 Dory Road, Sequim, W A 98382, USA
<br />AND
<br />CHARLESC.COUTANT
<br />
<br />Oak Ridge National Laboratory, Box 2008, Oak Ridge, TN 37831, USA
<br />
<br />ABSTRACT
<br />
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<br />Large catchment basins may be viewed as ecosystems in which natural and cultural attributes interact. Contemporary
<br />river ecology emphasizes the four-dimensional nature of the river continuum and the propensity for riverine biodiversity
<br />and bioproduction to be largely controlled by habitat maintenance processes, such as cut and fill alluviation mediated by
<br />catchment water yield. Stream regulation reduces annual flow amplitude, increases baseflow variation and changes tem-
<br />perature, mass transport and other important biophysical patterns and attributes, As a result, ecological connectivity
<br />between upstream and downstream reaches and between channels, ground waters and floodplains may be severed.
<br />Native biodiversity and bioproduction usually are reduced or changed and non-native biota proliferate,
<br />Regulated rivers regain normative attributes as distance from the dam increases and in relation to the mode of dam
<br />operation, Therefore, dam operations can be used to restructure altered temperature and flow regimes which, coupled
<br />with pollution abatement and management of non-native biota, enables natural processes to restore damaged habitats
<br />along the river's course. The expectation is recovery of depressed populations of native species. The protocol requires:
<br />[restoring peak flows needed to reconnect and periodically reconfigure channel and floodplain habitats; stabilizing base-
<br />flows to revitalize food-webs in shallow water habitats; reconstituting seasonal temperature patterns (e,g. by construction
<br />of depth selective withdrawal systems on storage dams); maximizing dam passage to allow recovery of fish metapopula-
<br />tion structure; instituting a management belief system that relies upon natural habitat restoration and maintenance, as
<br />opposed to artificial propagation, installation of artificial instream structures (river engineering) and predator control;
<br />and, practising adaptive ecosystem management.
<br />Our restoration protocol should be viewed as an hypothesis derived from the principles of river ecology, Although
<br />restoration to aboriginal state is not expected, nor necessarily desired, recovering some large portion of the lost capacity
<br />to sustain native biodiversity and bioproduction is possible by management for processes that maintain normative habi-
<br />tat conditions. The cost may be less than expected because the river can do most of the work,
<br />
<br />KEY WORDS: restoration; general protocol
<br />
<br />CCC 0886-9375/96/040391-23
<br />ihl 1996 by John Wiley & Sons, Ltd.
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