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Great Lakes
Article:
The
Fate of the Great Lakes:
Sustaining or Draining the Sweetwater Seas?
Diversions
published
February 1997
posted 10/28/2002
From Great Lakes
United's "Fate of the Great Lakes"
http://www.glu.org
Proposals for diversion
of water from the Great Lakes Basin periodically arise;
they always generate great controversy. Headlines a decade
apart show the heat that is generated: "Keep the
plug in Great Lakes" (Grand Rapids Press,
March 8, 1996), "Regions governors must keep
diversion to minimum" (Ann Arbor News, March
8, 1996), and "Feud grows over scheme to export water
to U.S." (Toronto Star, January 7, 1986),
"Grand Canal called Frankenstein"
(Toronto Globe and Mail, February 11, 1986), "Dont
Endanger Lakes to Aid Thirsty Big Apple" (Buffalo
News, September 14, 1985).
Impacts
of Diversions
The primary impact
of diversions out of the Basin is to permanently lower
lake levels. Individually, a diversion may seem inconsequential
because it is small, but cumulatively the impacts become
dramatic. Also, each diversion creates a precedent that
makes it harder to successfully argue against additional
proposals for diversions.
Permanently lowered
lake levels as a result of diversions would result in
significant environmental, social and economic harms.
Environmental impacts
There are a number
of environmental impacts from permanently lowered lake
levels. Among them:
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Water
quality in the Great Lakes could be detrimentally
affected. Within the diversion route itself, there
may be increases in water quality due to an increased
dilution of pollutants.1
However, water quality may be reduced where water
levels are lowered. Lower lake levels increase the
disturbance of contaminated sediments by ships and
by storms. This results in the release of contaminants
from the sediments, making them available to the
food chain. The contaminants are, as a result, passed
from fish to the birds, animals and humans who eat
them.2
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Wetlands
are particularly sensitive to changes in water levels.
Any loss of these wetlands affects the habitat of
the fish and wildlife who live there. Fish spawning
areas could be seriously affected. Loss of wetlands
also mean the loss of the numerous beneficial functions
of wetlands, which include groundwater recharge,
shoreline erosion prevention, temporary floodwater
storage, and water filtration by absorption of sediment,
chemicals, and nutrients.3
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Reduced
Great Lakes outflow could lead to saltwater encroachment
from the Atlantic Ocean up the St. Lawrence River.
This could have dramatic impacts on the freshwater
ecology as well as contaminating the drinking water
supply for Montréal and other communities in Québec.4
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Social and Economic
Impacts
Social and economic
impacts of permanently lowered lake levels include:
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Native
communities would be hit particularly hard by any
deterioration in the quality of the Great Lakes
ecosystem. Their culture and livelihoods centre
on the quality of the environment that they live
in.
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Decreased
lake levels would change beaches and shorelines,
and would leave docks and shipping and boat accesses
above the water line. This would decrease shorefront
property values.5
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Recreational
activities, such as boating, fishing, and hunting,
may also be negatively affected, which would hurt
the tourism industry.
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Water
intakes for plants that treat water for domestic
and industrial uses could be affected.6
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Hydroelectric
power production is proportional to the amount of
water available to be pumped through the system.
Any decreases in water quantity would adversely
affect the amount of energy available. Steam-electric
plants may also be affected by dramatic drops in
the level of Great Lakes water.7
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Commercial
navigation would be negatively affected by decreases
in water levels. The lower the water level, the
less commercial freight carriers can transport because
they need to reduce their weight to float higher
in the water. Lower water levels would lead to increased
demands for costly and environmentally hazardous
dredging and an increased demand for disposal sites
for contaminated dredgeate.
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The
negative effects of reduced water levels would create
greater demands to construct costly water control
structures such as dams to try to lessen water level
reductions in certain areas.8
Acrimonious debates over water level controls would
increase.
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Conflicts
between governments over water controls and exports
would increase. Relations between Canada and the
United States could be negatively affected.9
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In
1981, the U.S. Army Corps of Engineers estimated
that the annual cost of negative impacts on power
generation and commercial navigation of a 24,000
mld (6,500 mgd) diversion would be $US45 million.10
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Existing Diversions
Into the
Great Lakes Basin
The Portage Canal
Diversion
Built in the 1860s,
the Portage Canal connects the Wisconsin River to the
Fox River, which flows into Lake Michigan. As a result,
the canal diverts water from the Mississippi River basin
into the Great Lakes Basin. At times of high water levels,
as much as 240 mld (64.6 mgd) of water is diverted through
the canal.11
This canal is now used only for recreational purposes.
The Long Lac and Ogoki
Diversions
The Long Lac and Ogoki
diversions, completed in 1941 and 1943 respectively, divert
water into Lake Superior that would normally flow into
James Bay and from there into Hudson Bay.12
The Ogoki diversion
moves water through Lake Nipigon and the Nipigon River
into Lake Superior at a point 96 kilometres (60 miles)
east of Thunder Bay. This water was diverted to support
three hydroelectric plants on the Nipigon River.
The Long Lac diversion
diverts water through Long Lake and the Aguasabon River
into Lake Superior near Terrace Bay. The diversion provides
water for the hydroelectric plant near Terrace Bay and
to drive pulpwood down the river.
The combined average
daily flow of these diversions is 13,468 mld (3,620 mgd).
These diversions into the Great Lakes Basin are almost
75 percent larger than all current diversions out of the
Great Lakes.
The International
Joint Commission reported in 1985 that, although there
were no significant basinwide environmental effects from
these diversions, there have been important local environmental
effects, particularly on fish spawning areas and habitat.13
Because of the IJCs focus on U.S.-Canadian waters,
it did not address the impacts of these diversions on
the Cree people who live around James Bay, the watershed
from which these waters are diverted into the Great Lakes.
Existing
Diversions Out of the
Great Lakes Basin
The Forestport Feeder
Diversion
The New York State
Barge Canal, which has been in operation since the early
1800s, diverts a small amount of water to the Hudson River
watershed. Between 72 and 433 mld (19.5 and 117 mgd) of
the waters discharged from the canal into the Hudson River
watershed originate in the Great Lakes watershed.14
The original function
of this canal was for shipment of goods. Today it is mainly
used for recreational purposes.
The Chicago Diversion
In 1848, the Illinois-Michigan
Canal was opened to shipping traffic. This resulted in
the diversion of 240 mld (64.6 mgd) of water from Lake
Michigan at Chicago through the Chicago and Illinois Rivers
to the Mississippi River.15
At that time Chicagos
sewage flushed into the slowly moving, almost stagnant
Chicago River and thence into Lake Michiganthe source
of Chicagos drinking water. In 1885, 90,000 people
died in Chicago from cholera as a result of this situation;
this was over one-tenth of the citys population.
Because of this disaster,
the Drainage and Water Supply Commission and the Sanitary
District of Chicago were formed. The commission built
a new channel and control structures to reverse the flow
of the Chicago and Calumet Rivers so that sewage from
Chicago would flow through the Illinois River to the Mississippi.
The canal was completed in 1900.
During the 1920s,
the Chicago diversion was as high as 24,000 mld (6,463
mgd).16
In 1967, the U.S. Supreme Court limited the diversion
to 7,600 mld (2,068 mgd), the level it is supposed to
be at today.
The Chicago diversion
has three components. The first component, 62 percent
of the diversion, provides the water supply for the 5.7
million residents of northeast Illinois.17
The second component is a direct diversion from Lake Michigan
into the Illinois River and Canal system for safe navigation
and to increase flow in order to improve water quality
in the Chicago area. The third component, 20 percent of
the allowed diversion, is stormwater runoff that would
have flowed into the Chicago River and from there into
Lake Michigan, but which now flows the opposite direction
into the Mississippi watershed.
It is expected that
by the year 2000 Chicagos population will have increased
by one million people. This is sure to create new pressures
to increase the size of the Chicago diversion.18
The level of flows
at this diversion has always been a controversial topic
because it is the largest diversion out of the Great Lakes
Basin and always threatens to increase. The current allocation
of 7,600 mld (2,068 mgd) averaged over a forty-year period
was established by a U.S. Supreme Court decree issued
in 1967 and amended in 1980.19
In 1995, a dispute
arose between Michigan and Illinois because approximately
740 mld (200 mgd) more water was being diverted from Lake
Michigan through the Chicago diversion than allowed by
the court decree. Illinois argued that a "paper change
rather than a physical change" in the diversion had
occurred.20
The state said new, more accurate velocity flow meters
were being used to measure the diversion and that canal
locks maintained by the U.S. Army Corps of Engineers were
leaking. Michigan argued that Illinois "cant
pretend that one number is another."21
The federal government
and the eight Great Lakes states took this dispute to
mediation. Illinois and Michigan requested that the Army
Corps of Engineers be granted authority under the Water
Resources Development Act to proceed with necessary repairs
to eliminate leakage through the locks.22
In October 1996, the
concerned parties came to an agreement in which Illinois
agreed to reduce the outtake of water from Lake Michigan
to the amount set in the 1967 and 1980 court decree. In
return the eight Great Lakes states agreed not to take
legal action over the withdrawal violations that had already
occurred.23
The Pleasant Prairie
Diversion
The village of Pleasant
Prairie, Wisconsin, straddles the Great Lakes and Mississippi
Basins. Before 1990, Pleasant Prairie relied on groundwater
for its water supply. In 1982, when two of the villages
wells were found to be contaminated with radium at levels
four times higher than federal standards, the state notified
the village that it would have to correct the radium problem.24
Although there were
a number of options available to the village, including
a cleanup of the radium contamination, the village decided
to bring Lake Michigan water to one of the wells through
a diversion that would discharge into the Mississippi
River basin. According to the villages officials,
"this was by far the least expensive, the fastest,
and the most practical [option]."25
In December 1989,
the state gave approval for the diversion of 12 mld (3.2
mgd) of water to a well in Pleasant Prairie serving four
thousand users in three subdivisions, a mobile home park
and a factory.
Because of concerns
raised by the province of Ontario, several of the Great
Lakes states and citizens groups led by Great Lakes
United, the state of Wisconsin termed the diversion a
"temporary" one. The agreement between the village
and the state requires Pleasant Prairie to build a pipeline
to return effluent from that section of the village to
Lake Michigan by 2010.*
Since the diversion
began in 1990, development in the area served by the well
has increased substantially. Village planners have approved
several new developments, including 500- and 156-lot subdivisions.
* Strangely, there
are two versions of the compliance agreement between the
state and Pleasant Prairie. One, which is signed, does
not include the requirement to return the water by 2010.
The unsigned agreement contains the requirement to return
the water.
Existing
Inter-Basin Diversions of Great Lakes Waters
Out
of the Great Lakes Basin
1
Chicago, Illinois, diversion including Indianas
Calumet River system, since 1800s, 7,600 million
litres per day (2,068 million gallons per day).
2
Pleasant Prairie, Wisconsin, diversion, since 1990,
up to 12 mld (3.2 mgd).
3
Forestport Feeder diversion to New York Barge Canal,
since 1800s, 72433 mld (19117 mgd). Diverts
Lake Ontario headwaters stream in the Adirondack Mountains
into the Hudon River basin part of the canal.
Into
the Great Lakes Basin
4
Ogoki diversion, Ontario, and
5
Long Lac diversion, Ontario, both since 1940s.
These two diversions total 13,468 mld (3,620 mgd).
6
Portage Canal, Wisconsin, diversion, since 1800s, 240
mld (65 mgd). Diverts the Mississippi Basins Wisconsin
River into the Great Lakes Basins Fox River.
Proposed
Diversions
Over the years numerous
proposals for major diversions have been promoted.26
Some of the more grandiose of these that have not come
to fruition include:
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A
plan by North American Water and Power Alliance
and the MexicoUnited States Hydroelectric
Commission to drain Great Lakes water into the Mississippi
River and ultimately to Mexico (196468).
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A
plan to build a slurry pipe using water to transport
coal from Lake Superior to Wyoming (1981).
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A
project to pipe Great Lakes water to the High Plains
states and the Southwest (1984).
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A
project to blast a four-hundred-mile-long paved
canal from Lake Superior to the Missouri River in
South Dakota (1983).
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Legislation
to blast a canal from Lake Erie to the Ohio River
(198691).
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A
federally funded plan to punch a hole in the bottom
of Lake Michigan to drain water through bedrock
layers for use in southern Illinois (1987).
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Great Recycling and
Northern Development (Grand) Canal Project
This $100 billion
project has been called the "darling of the engineering
industry." First proposed in 1959, this enterprise
continues to be on the drawing board and periodically
rises to a higher profile.
The Grand Canal project
involves building a dyke across James Bay, turning the
southern part of this salt water body into a fresh water
lake. This water would then be diverted to the Great Lakes,
where it would be sent on to the U.S. Midwest or to Lake
Diefenbacker in Saskatchewan and then on to the U.S. South,
Southwest, and perhaps Mexico.27
According to Tom Kierans,
the developer of this project and its chief promoter,
the prime benefits of this diversion would be that Great
Lakes water levels would be stabilized and water-short
areas of the Canadian and U.S. Midwest would have a secure
water supply.28
Those who oppose this
project fear disastrous effects from the reversal of water
flows on the James Bay ecosystem and on the First Nations
peoples who reside in the area.29
The First Nations peoples believe that the project would
"destroy the James Bay fisheries, threaten migratory
bird populations and jeopardize general water quality."30
Although such a large
scheme may seem unlikely to occur, it should not be dismissed
as a pipedream. Although GRANDCo, the company formed to
coordinate this project, is in a "state of suspension,"
Kierans is still actively promoting the idea.31
Some observers believe
that large-scale engineering projects such as the Grand
Canal were foreseen in the U.S.-Canada-Mexico free trade
discussions; before his appointment as Canadas negotiator
for the Canada-United States Free Trade Agreement, Simon
Reisman was a director of GRANDCo Ltd.32
It has been suggested, for example, that the Rafferty
and Alameda dams in Alberta can only be understood as
a part of a larger Grand Canal scheme.33
Rather than building
the complete project at once, the more likely scenario
would be the construction of small parts of the project
one at a time.
New York City
During a drought in
the mid-1980s, New York City officials eyed Lakes Erie
and Ontario as potential sources of fresh water. The floating
of the idea immediately led to vehement reactions. The
Buffalo News wrote an editorial entitled "Dont
Endanger Lakes To Aid Thirsty Big Apple" (September
14, 1985). The proposal was quickly dropped.
This was not the first
time that such an idea was presented and dropped. In 1964,
the "North American WatersA Master Plan"
proposed to pipe vast quantities of water from Lake Ontario
to New York City.34
Each summer that New York City experiences a drought ideas
for diverting water from the Great Lakes resurface.
Lowell, Indiana
Lowell, Indiana, is
five miles outside of the Great Lakes watershed. The communitys
groundwater had fluoride levels exceeding U.S. federal
water quality standards; in 1987 the federal government
issued Lowell an order to comply with federal standards
by 1989.35
Lowell responded by
seeking to divert Lake Michigan water through the Gary-Hobart
Water Company at the rate of 4 mld (1.2 mgd).36
Québec, Ontario and
Michigan formally objected to the diversion. Great Lakes
United coordinated citizens groups opposed to the
project. Finally, Michigan used its veto under the Federal
Water Resources Development Act of 1986 to stop the project.
Mississippi River
In the summer of 1988,
a severe drought caused the Illinois and Mississippi Rivers
to fall to record lows.37
This caused navigational problems in the Mississippi and
created serious problems for farmers trying to grow crops
in the U.S. Midwest.38
This led to calls by the state of Illinois and several
U.S. senators for the U.S. Army Corps of Engineers to
triple the flow of the Chicago diversion for one hundred
days and possibly longer.39
This proposal raised considerable public alarm in the
Great Lakes Basin.
After studying the
situation, the Army Corps of Engineers concluded that
the increased diversion would not make a "significant
difference either in the navigability of the [river] channel
or in the need for continued dredging of the river crossing
as shoaling occur[ed]."40
The proposal was dropped.
The precedent for
increasing the Chicago diversion because of low water
levels in the Mississippi was set in 1956.41
A major drought from 1952 to 1956 resulted in low flows
on the Mississippi River. As a result, in 1956, the U.S.
Supreme Court granted a permit to increase the flow through
the Chicago diversion for seventy-six days.
Changes in Mississippi
River water levels are likely to create recurring calls
in the future for either short- or long-term increases
in diversions from the Great Lakes.
Kenosha, Wisconsin
Between 1991 and 1992,
the city of Kenosha built a water line from Lake Michigan
to supply water to a newly annexed area slated for development.
Instead of returning the water to the Great Lakes, Kenosha
hooked up to Pleasant Prairies waste treatment system.42
This meant that the water was diverted to the Mississippi
watershed through the newly built Kenosha diversion.
Investigations by
Great Lakes United and the Lake Michigan Federation revealed
this illegal connection and diversion. The groups
lobbying of Wisconsins governor resulted in Kenosha
being forced to disconnect from Pleasant Prairies
system and return their water to the Great Lakes Basin.43
Crandon Mine, Wisconsin
Crandon Mining Company,
owned by Exxon and Rio Algom, proposes to develop an underground
hardrock metallic sulfide mine near Crandon, Wisconsin,
in the Wolf River Basin, which is in the Great Lakes Basin.
The company wants to mine 55 million tons of ore, extracting
primarily copper and zinc and some lead, silver and gold.
The operation of this
mine would result in the diversion of water from the Great
Lakes Basin. To keep the mine from being flooded by groundwater
from the surrounding aquifer, Crandon Mining Company would
have to continuously pump water out of the mine twenty-four
hours a day for more than thirty years.
The proposed mine
would be located at the headwaters of the Wolf River.
This pristine waterway is a state Outstanding Resource
Water and a protected National Wild and Scenic River.
Crandon Mining Company proposes to pump out the withdrawn
groundwater through a thirty-eight-mile-long pipeline
to the Wisconsin River to avoid water treatment costs
necessary to return the water to the Lake Michigan watershed.
Water loss at the
headwaters additionally threatens area lakes, streams
and wetland and is a diversion of Lake Michigan waters
into the Mississippi River watershed. The water loss from
the Great Lakes Basin from this proposal is estimated
to be approximately 3.7 mld (1 mgd).44
As of February 1997,
this proposal was still under consideration by the U.S.
Army Corps of Engineers. The proposal is opposed by the
Mole Lake Reservation, a large number of local organizations
and local governments along both the Wolf and Wisconsin
Rivers.
Akron, Ohio*
In early 1996, Akron,
Ohio, proposed to divert 13 to 19 mld (3.4 to 5 mgd) of
water each day from the Great Lakes Basin. The water would
go to unincorporated suburbs beyond the citys limits
just over the border of the Great Lakes Basin. While admitting
that this is officially a diversion from the Great Lakes
Basin, Akron officials say that the diversion will not
have negative effects on the Great Lakes because as much
water will be returned to the Great Lakes as is withdrawn.
This will be achieved through a combination of discharges
from the citys sewage treatment plant and water
diverted from the Ohio River watershed through the Ohio
Canal.45
By promising "no
net loss" of water from the Great Lakes Basin, Akron
hopes to avoid the controversy usually associated with
diversions of water from the Great Lakes. Nevertheless,
environmental groups are opposed to the proposal for two
main reasons. The "no net loss" concept does
not address water quality issues. Water returned after
use usually is degraded in quality. Also, the proposal
is a precedent-setting end run that numerous other municipalities
just beyond the edge of the Great Lakes Basin would use
to try to justify diversions from the Great Lakes.
The decision on the
Akron diversion proposal will be made after it is reviewed
by the other Great Lakes states and provinces under the
U.S. Water Resources Development Act and the Great Lakes
Charter.
* Since publication
of this document, in spring 1998, the eight Great Lakes
governors approved this diversion proposal. In order to
obtain Michigan's approval, Ohio acceded to its demands
that Ohio to assume responsibility for the diversion and
assure that the returned water was not polluted.
Potential for Requests
for Diversions to Areas Adjacent to the Great Lakes Basin
In 1993, Great Lakes
United staff member Bruce Kershner and intern Carl Bolster
studied the likelihood that communities just outside of
the Great Lakes Basin would seek to divert Great Lakes
water for public drinking water and navigational purposes.*
46
The study concluded
that the areas with the highest potential to raise demands
to divert water from the Great Lakes are Kenosha-Pleasant
Prairie (Wisconsin), Lowell-Gary-Hobart (Indiana), Waukesha-New
Berlin-Milwaukee (Wisconsin), Akron-Cleveland (Ohio),
Chicago (Illinois) and New York City. Recent diversion
requests are proving the accuracy of this study.
* This study did not
include Michigan and Ontario because water withdrawals
here would be unlikely to result in diversion of waters
out of the Great Lakes Basin.
Diversions
of Water Within the
Great Lakes Basin
In several places
around the Great Lakes, water is diverted from one place
to the other, bypassing waterways or lakes in between
the withdrawal and discharge points. For example, the
city of Detroit withdraws its drinking water from Lake
Huron and discharges contaminated effluent from its sewage
treatment plant into the Detroit River. This robs the
St. Clair River and Lake St. Clair of part of their normal
flow.
Similarly, the city
of London obtains its water supply from a point on Lake
Huron over 50 kilometres (30 miles) away and discharges
its sewage treatment plant effluent down the Thames River
to Lake St. Clair. It thus diverts water past the St.
Clair River.
Such diversions within
the Great Lakes Basin affect water flows in certain sections
of the Great Lakes system and, as a result, harm wetlands
and fish, bird and wildlife habitat.
For the past several
years, the Ontario government and several municipalities
in southern Ontario have been considering proposals by
private companies to build a $500-million pipeline to
divert 190 to 229 mld (50 to 60 mgd) of water from Georgian
Bay on Lake Huron to provide water to York, Peel, Halton,
Wellington and Waterloo Regions.48
This intrabasin transfer would bypass much of Lake Huron,
all of the St. Clair and Detroit Rivers, and, depending
on the municipality served, Lake Erie and the Niagara
River.
According to a document
prepared by TransCanada Pipelines, the company that originally
proposed building the pipeline, "the principle objective
for the proposed system is to replace existing groundwater
supplies in communities where it is found to be chronically
lacking from a quality, quantity or long term reliability
perspective."49
Citizens groups
have major concerns about the ecological disruptions that
would occur at both ends of the pipeline and along the
major part of the Great Lakes that would be bypassed by
such a diversion. They believe that it would be more cost
effective to remediate contaminated groundwater and practice
water conservation than to build the pipeline. They also
believe that the pipeline would encourage growth beyond
the natural carrying capacity of the local watersheds
and would lead to the destruction of wetlands, which are
crucial to the recharge of groundwater supplies.50
York Region, just
north of Toronto, has most actively pursued this proposal,
after awarding a tender to provide future water supplies
to a consortium of Consumers Gas and British Northwest.
In 1996, they came out with a proposal to draw 655 mld
(177 mgd) of water from Georgian Bay and discharge treated
sewage into Lake Ontario. Several citizens groups, including
the Georgian Bay Association, the Safe Sewage Committee,
the Canadian Environmental Law Association and Great Lakes
United, objected to the proposal on environmental grounds.
In December 1996, York Regional Council dropped the proposal
to divert water from Georgian Bay, primarily for economic
reasons.
The
Thirst of the Rest of the Continent
Groundwater is being
mined at a rapid rate in several major parts of North
America. The Worldwatch Institute points out serious depletion
of groundwater in the High Plains of the United States
(the Ogallala Aquifer), California, the southwestern United
States, Mexico City and the Valley of Mexico.51
The Commission for
Environmental Cooperation, which was set up under NAFTA,
observed that "in 1995, the lack of water in northern
Mexico killed crops and cattle, while fish and other aquatic
life died from rising salt levels in rivers."52
The CEC concluded that this situation is likely to worsen.
These problems led Mexico to ask the United States for
alternative water supplies; the United States refused
the request.
As water sources throughout
North America are depleted, the grand schemes that have
thus far been set aside may well become more viable and
the need ever more compelling. Generally the estimate
of impacts on water levels across the Great Lakes from
a 24,000 mld (6,500 mgd)*
diversion anywhere in the Great Lakes is a decrease of
0.15 metres (half a foot).54
A 24,000 mld diversion would be small in comparison with
the thirst that these major areas of the United States
and Mexico may experience.
* A flow this size
would cover a football field with four inches of water
every second.53
Groundwater
Depletion in North America, circa 1990
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Region/Aquifer
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Estimates
of Depletion
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High
Plains Aquifer System, United States
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Aquifer
underlies nearly 20% of U.S. irrigated land. Depletion
12 billion cubic metres (bcm) per year, 325 bcm
to date15 times annual flow of the Colorado
River. More than 2/3 occurred in the Texas High
Plainsirrigated area dropped 26%, 1979-89.
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California
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Groundwater
overdraft averages 1.6 bcm per year, 15% of the
state's annual net groundwater use. 2/3 occurs in
the Central Valley, the U.S. vegetable belt.
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Southwestern
United States
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Water
tables have dropped more than 120 metres (393 feet)
east of Phoenix, Arizona. Projections for Albuquerque,
New Mexico, show a further drop of 20 metres (65
feet) by 2020 if withdrawals continue at current
levels.
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Mexico
City and Valley of Mexico
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Pumping
exceeds natural recharge by 50% to 80%. This has
led to falling water tables, aquifer compaction,
land subsidence, and damage to surface structures.
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Historical
Lessons of Great Lakes Diversions
The existing diversions
in the Great Lakes and the numerous proposals that have
not come to fruition provide us with some important lessons
that we must learn from for the future.
Each diversion is
of basinwide concern.
Because the Great
Lakes system is a hydrologically integrated system, changes
in levels in one part of the Basin affect other parts
of the Basin. For example, the Chicago diversion not only
lowers Lake Michigan levels (by 6 centimetres or 2.5 inches);
it also lowers the waters of Lake Erie (by 4.5 centimetres
or 1.75 inches) and Lake Ontario (by 3 centimetres or
1.25 inches).55
In addition, even very small diversions have basinwide
implications, making it more difficult to deny future
applications for similar types of diversions in other
parts of the Basin.
Requests for transfers
adjacent to the Great Lakes Basin will increase.
Recent examples show
that the demands from communities just beyond the border
of the Great Lakes Basin will increase for two main reasons:
(i) contamination of groundwater leads communities
to look to the Great Lakes as a cheaper way of getting
water than cleaning up and protecting their groundwater
supplies; and (ii) the desire of communities to grow in
terms of both residential subdivisions and industrial
and commercial enterprises leads them to look to the Great
Lakes as a new water source.
Demands for Great
Lakes water from distant communities will increase.
As history has shown,
when regions of any other part of the continent experience
a drought or draw down their water reserves, their eyes
turn enviously to the luxury of waters in the Great Lakes.
This situation will not stop. Indeed, these calls will
become ever more urgent.
The thirst of the
people beyond the Basins borders for water will
never end and, as a result, diversions will never be a
dead issue in the Great Lakes Basin. Therefore, we must
have clear policies on how we will deal with diversions.
The adequacy of present
efforts to control Great Lakes diversions will be discussed
in the next two chapters.
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