Making predictions that change the future: forecasts and alternative visions for the Illinois River : Keynote speech at the Third Biennial Governor's Conference on the management of the Illinois River System

56 Pages·1994·0.88 MB·English

by  Sparks, Richard E

yiyi^M^jUL c^^tLt;,
ILLINOIS
^==\
f NATURAL HISTORY
SURVEY
Making Predictions That Chang© The Future:
Forecasts and Alternative Visions for the Illinois River
Keynote Speecli at tlie Tliiid Biennial Guvenior's Conference on the
Management of tlie Illinois River System
Center for Aquatic Ecology
Richard E. Sparks
Illinois Natural History Survey
River Research Lab
Forbes Biological Station
P.O. Box 590
Havana, IL 62644
^
December 1993
Aquatic Ecology Technical Report 93/18

'TtulaJuJ-
MAKING PREDICTIONSTHATCHANGETHE FUTURE:
FORECASTS AND ALTERNATIVE VISIONS FORTHE ILLINOIS RIVER
Keynote Speech
Third Biennial Governor's Conference
on the
Management of the Illinois River System
Hotel Perc Marquette
Peoria, Illinois
21-22 September 1993
Presented by
Richard E.Sparks
River Research Laboratory
of the
Stephen A.Forbes Biological Station
Illinois Natural History Survey
Havana, IL 62644
Text prepared 4 January 1994

IllinoisNaturalHisiorySurvey
CenterforAquaticIxology
TechnicalRcpc-rt93/18
Making Predictions That Change The Future: Forecasts and
Alternative Visions for the Illinois River
Keynote Speech attheThirdBiennialGovernor's Conference
ondieManagementoftheIllinoisRiverSystem
by
Richard E. Sparks
IllinoisNaturalHistorySiu^'cy
RiverResearchLaborator)'
ForbesBiologicalStation
P.O.Box590
Havana,IL 62644
RRiicchhaarrddEE..SSppaarrkkss 7/ DavidP.Philipp,Director
PrincipalInvestigator CenterforAquaticEcology

This paper originally was presented as a keynote
address at the Third Biennial Governor's
Conference on the Management of the Illinois
River System, Hotel Pere Marquette, Peoria,
Illinois, 21-22 September 1993. It was
published in the proceedings of the conference
in 1994 by the University of Illinois Water
Resources Center. Copies of the proceedings are
available from:
Heartland Water Resources Council
of Central 111inois
Commerce Bank Building
415 Main Street, Suite 828
Peoria, Illinois 61502-1115
This paper should be cited as:
Sparks, R.E. 1994. Making predictions that
change the future: forecasts and
alternative visions for the Illinois
River. Holly Korab, ed. Proceedings of
the Third Biennial Governor's Conference
on the Management of the Illinois River
System, Peoria, IL, 21-22 September 1993.

Sparks 1 January 1994 Page 1
ABSTRACT
The Illinois River ranks among a world class of large river-floodplain ecosys-
tems that includes the Mississippi, the Amazon, and the Nile. These rivers
are dynamic ecosystems characterized by seasonal floods that spread over large
floodplains and enhance biological productivity. Despite a century of altera-
tions, the Illinois River retains approximately half its floodplain and a
floodpulse, and therefore is one of only three large river-floodplain ecosys-
tems in the United States recommended for restoration by the National Research
Council Committee on Restoration of Aquatic Ecosystems (1992). It is part of
the Upper Mississippi River System, which Congress recognized as a "nationally
significant ecosystem" in the Water Resources Development Act of 1986. Al-
though no restoration can ever be perfect, it is possible to restore processes
that enable a disturbed ecosystem to maintain, repair, and even rejuvenate
itself. Impediments to restoration include incomplete public ownership of
underwater lands needed for restoration projects; continuing invasions of
nonnative pests such as the zebra mussel; and toxic episodes that can undo
many years of pollution abatement and ecosystem recovery. These obstacles can
be overcome by easements or purchase of land; by stricter federal regulations
and better dispersal barriers; and by new continuous biological monitoring
systems that provide early warning of toxicity so that corrective action can
be taken. The predisturbance reference period for the Illinois should be the
19th century, when the river maintained itself in a dynamic equilibrium with
no human intervention, rather than more recent periods when the river was
disequilibrated by watershed alterations, Lake Michigan diversion, and naviga-
tion dams. Much can be learned from retrospective analysis of available data
on predisturbance land forms, vegetation patterns, and hydrographs that could
be applied to contemporary restoration of the river. Current efforts to
rehabilitate and enhance portions of lakes or lands for a particular human use
or highly valued species are expensive, interim measures that require continu-
ing maintenance and may, in fact, worsen the excessive sedimentation and water
level fluctuations they seek to mitigate. Ecosystem restoration saves money
in the long run, because natural services are restored, instead of requiring
costly human intervention with its considerable risk of failure. These serv-
ices include self-repair following natural or human disturbance; flood convey-
ance and storage; water purification; fish and wildlife production; and pres-
ervation of biodiversity.