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cGRE, I, la ,IFST. LAWRENCE RIVE^

I What it Means and How it Works TABLE OF CONTENT3 1. Introduction...... 2. The International Joint Commission ...... 3. The Great -St. Lawrence River System ...... 4. Superior Regulation ...... 4.1 IJC Orders Of Approval ...... 4.2 Regulatory Facilities ...... 6 4.3 Regulation Plans and Their Operations . . ...6

4.4 Experience of Regulation ...... 8 5. Lake Regulation ...... 9 5.1 IJC Orders Of Approval ...... 9 5.2 Regulatory Facilities ...... ,...... 9 5.3 Regulation Plans and Their Operations ...... 9 5.4 Experience of Regulation ...... 11 6. Who You Can Contact About Lake Regulation ...... inside back cover

This publication is produced jointly by the Ontario For additional copies of this publication. Region of Environment , and the North please contact: Central Division of the U.S. Army Corps of Environment Canada, Water Planning and Engineers. Authors: P. Yee, R. Edgett and A. Management Branch, Ontario Region, P.O. Box Eberhardt. Illustrations: Lount Graphics Limited, 5050, Burlington, Ontario L7R 4A6; or Hamilton, Ontario. North Central Division, U.S. Army Corps of Engineers, 536 South Clark Street, Chicago, First Edition: May 1990 Illinois 60605-1592

RECYCLED PAPER HAS BEEN USED TO PRODUCE THIS PUBLICATION 1. INTRODUCTION the St. Marys and St. Lawrence Rivers. The six-member 1JC is supported by staff at its e -St. Lawrence River System is offices in Washington, D.C. and in and one oP 's mst imporant natural Windsor, Ontario. The IJC also relies on the services T"resouces. The &s and rivers provide count- of government and public experts from both countries less benefits to the ream, including a source of to conduct its studies on such issues as regulation electricity. As byh&t~# pr&veEaped in the of the Great Lakes-St. Lawrence River. system, darns were W 0 artificidy regalate the The process that leads to the 4C approving ob- owflows from two of rhe he Grear bks: Lake stmctions or diversions of Great Lakes water consists Superior and . This boom explains of several major steps. First, the entity interested in when and why tit& regulation came about, how it constructing and operahg a dversion kility on waand its ben& and limitations. the Great Lakes imst apply to tk UC for approual.

NaturaC Fuctors Aflecting Lake LLVE/S 2. THE INTERNATIONAL JOINT The 1JC then conducts studies, and in many cases, COMMISSION appoints a study board or a panel of experts to carry out any detailed technical investigations. Public th the signing of the hearings are also held to receive comments on the Treaty of 1909, Canada and the United application from Ehe pdlk and various levels of wStates established the International Joint governments. Thr- this pxess, the IJC identifies Comrrtission (IJC) to oversee Wesconcerning what impacts these fadlities could have on the levels boundary and wansbmda-y waters shared by the and flows of the &eat Lakes, and thus considers two countries, lncllrding heGreat Lakes. The Treaty the merit of each qpllcation based on a variety of requires the 1)C apprm certain uses, obstructions viewpoints and technical information. or diversions of bornday waers if these operations If the IJC approves tbe application, its consent affect the natural level or flow of the boundary (called Orders af Approval) may include conditions waters in the other country. In addition, under the and criteria govmnCng the construction and operation Tkeaty, Canada and the can ask the c4 the kilties. In some cases, the IJC also requires 1Jc to conduct studies and make recamndatims that a hbbe established to develop regulation on specific problems along the crwmmn frontier. plans and t~ snpervise the operation of these facili- Two examples of the IJC a~hcnityhm been to ties in order to ensure that the conditions and criteria approve the development of hydropower projects in in the Orders are met. Review of IJC authorized projects and the Orders warn er&from the land both provide water to the has ccartinued over the years, and changing d-qmm, whBe evaporation lowers water quantities tions have required periodic revisions to the Mm ha tk hh,Persistently high or low precipitation adthe regulation plans. When reviewiag its Odes, over wvedyears is the main natural factor causing the T)C again considers the views of the pl% the extreme high or low lake levels. Other natural advice of its boards and the views and comments d factors whkh impact lake levels and outflows governments. include fbw restrictions due to ice or aquatic weed grmh h ttpe outlet rivers. Several human activities 3. THE GREAT LAKES- also &ct hlsand flows, including dredging of ST. LAWRENCE RIVER SYSTEM chamnets, water diversions, consumptive uses (water taka out and not returned to the system; for e Great Lakes is a system of nahual reser- eaqk,water used for drinking or industrial uses) voirs. , at the top of this chain, and Hou regulation. T"flows into through the St. Marys Llhe Superior's water level fluctuates somewhat Rim. Water also flows out of Lake to less rha~those of the downstream lakes. Since Lake Huron through the broad and deep Straits of 1900, the mal range of fluctuation - the difference Mxkinac. Since and Lake Huron stand betwcm rhe maximum monthly average and the at the same elevation, they are often referred to as mhhm monthly average - has been about four ate lahc hydrologically, or Lakes Michigan-Huron. feet (1.2 metres). The Lake Superior RmL&e Huron, water flows through the St. Clair is about two and one-half times the size of the River, Lake St. Clair and to . lake's surface area, and thus land runoff contributes Ldre Erie flows into Lake Ontario via the significant supplies of water to the lake. In fact, Wr. Lake Ontario, the lowest lake in the chain, flows monthly water supplies to the lake have been esti- into che Atlantic Ocean via the St. Lawrence River. mated to be as high as 4.7 times the lake's average The water levels of the Great Lakes change in re- outflow. Supply of this magnitude would raise the sponge to mylic$.~~~. Over-lake preciiitah & i&s kdant? foot (0.3 metre) in one rnmth abae

Gwar Lakes-St. Lawrence River Basin unless it is offset by the lake's outflow. fluctuation is about 6.6 feet (2 metres). Lake Ontario is quite different horn Lake Superior. Several sectors of society, or interests, are affected The Lake Ontario drainage basin, which includes all by the inevitable variations in the lev& and of the land and water of the tapper takes as well as outflows of the Gmt Lakes. Generally, they fal ink^ land surrounding the lake, Is about 40 times the four categories: shore property owners, fkh md size of the lake itself. Hence, warsupplies - and wildlife enthusiasts, navigation interests and the changes in these supplies - are also much larger people involved h the hylropower industry. than those for Lake Superia. For example, the Each of these interests have unique concerns and highest recorded monthly water supplies to Lake preferences when it cmsto Great Lakes levels and Ontario are equivalent to 4.8 feet (i .5 metres) of outflows. Most shore property owners, fa examp)e, water on the lake. These smistks, along with the benefit from stable water kvek and a reduction of limited storage capacity of the lake and the diver- the extremes in hgh or Low lake levels. Up to a hit, sified interests located on Lake Ontario and in the navigation is best served by hgR lake lev&. Hi* St. Lawrence River, make the regulation of Lake flows also increase hydropower generation. Fish zrad Ontario complex. Lake Omstotal range of wildlife interests, however, tend to be divided as to Tdble 1 Dimensions of the Great Lakes-St. Lawrence River Shoreline Length Water Depth Area Volume Mainland Island Average Maximum Sq Mi Cu Mi Feet (Sq Km) (cu Km) (Km) (Km) (Metres) (Metres) Lake Superior

St. Marys River

Lake Michigan

Lake Huron

St. Clair River

Lake St. Clair

Detroit River

Lake Erie

Niagara River

Lake Ontario

St. Lawrence * 235 30 1 352 * (610) (484) (567) * * 960 705 466 * * (1,540) (1,130) (750) * From Lake Ontario to CornwallIMassena. * * From CornwallIMassena to Ile d'orleans near Quebec City LAKE SURFACE ELEWAT MeSt. Lawrence (INTERNATIONAL GREAT m&iv Lake St. Francis

Montreal Harbour

Gulf of St. Lawrence

Distance 2,200 miles - 3560 kilometres F I @&? Gkat ~ks-St.Lawrence River Sysrem dmfdrgteL, kw uy stable lake levels are beneficial. as to maintain the level of Lake Superior as nearly Sish and kid to live in wetlands, which past as may be between the levels 600.5 and 602.0 feet ;dud&'& ml as vital to the ecological (183.0 nd W.5 mtns) rd io such mmner as kattb d& Lskes. Fluctuations in lake levels not to Mewith nifd@h." IWtq?t range dm rend be warage and support a wide diversity was smala than the hksa-kal ram@ pcia 0 1914 dpUaPd admd life. andwascm&hd~Llndcx~. The 1914 amsent c&f lus beer upckd over sd 4. LA#F SUPERIOR REGULATION the years met the drarm and requirewna L the Geeat Lab-% Lawreme River 4.1 pC Os&m 4 Approval System. Far w,supplmmury arders were In l913, AmSteel Corporation in Canada and issued irr lW'& 1979 ad agsh in 1485 to protect &E MkhQa bahern Power Company in rkc UmW ~~p~~incberapiksduaofeheSt. S&ks applied m Qe IJC for approval, a6 wedby Margs River. A 1973 syqhmUay o&r dso per- tk reOP Waters Reaty, to chat of m&€ed& redeveIopraeRt afclr Rndanwropower the rrarcr d fbe Se. Marys River for hykpvcr cwk&es at Sadt W.Mack CMtario. mn.&r a series of public head- acid a 1P1m,*l)E~~adedtrsordcrof mhhlsady, rhe IJC approved the reguest ad Aplrrmd kkwlng an exocrrsk sue by ifs lesle$ a~Or& d Approval in 1914, wU3sped- IneadGreat Lakes Lev& Bcmd. a series of Bad a k of eondCtions that were to be in fk lJCpllUc~~an8~~nfck a.4 operation of the hydropower- facili- GovernmeRts. While aU pevhs adas required a.Tbc l$C (3rda also established the International that oniy the LMeb of Lale: Sqmbr be asidered Uhe Superiar Bwd of Control to oversee the opera- in determining the outflows, the 1979 aracndumt tbRs d the &Wcs in the St. Marys River. The Lake requires that the levels of Lakes Michigan-Hzmn also Spa$x Board has two members: one representing be taken into account in determining Sspedarrs the United States from the Army Corps of Engineers outflows, also known as systemic regulation. lk adam! qmsendng Canada from Environment objective of systemic regulation is to prcrPide BtRcfks miada. throughout the Great Lakes System. The 1979 order Tlu 1% @lished the basic objectives also specified that adequate flows must be ensured -Pnd Pd6 b, reglulation. One condition states for fish habitat in the rapids section of the St. thrtL 'Al tompesathg works . . . shall be operated Marys River. A provision for extreme water supply conditions St. Marys River that resulted from hydropower was also contained in the 1979 order. Thus, during developments. Gate openings are adjusted to achieve, extreme water supply conditions, the IJC will indicate along with the flows through the other facilities, the the appropriate outflows from Lake Superior, taking total monthly flow specified by the regulation plan. into account upstream and downstream interests. When the regulation plan calls for low flows, reduc- tions in the diversion of water for hydropower 4.2 Regulatory Facilities generation will usually occur. At times of extreme Hydropower plants and navigation locks have all high flows, all gates at the Compensating Works can been built and operate using the waters of the St. be opened. In an emergency, the navigation locks in Marys River. The hydropower plant in Canada is the United States have been used temporarily to operated by Great Lakes Power Limited, while in the increase the river flow. United States, one hydropower plant is operated by the Edison Sault Electric Company and another one 4.3 Lake Superior Regulation Plans and by the U.S. Army Corps of Engineers. The navigation Their Operations locks, four in the United States and one in Canada, Just as the 4C Orders are modified in response to the also use a small portion of the flows in the river. changing conditions on the Great Lakes, the regula- Navigation lock operations are directly under federal tion plan for Lake Superior is also updated and authorities in either country, however, and are not improved to meet the changing conditions specified under the supervision of the 4C or its Lake Superior in the Orders. The development and testing of regu- Board. lation plans, using historical water supplies to the The construction of the 16-gate Lake Superior Great Lakes, is a key requirement in the 4C Orders. Compensating Works was a key requirement in Four different regulation plans were used to regu- the 4C's 1914 order. As its name suggests, the late Lake Superior from 1928 to 1979. All these Compensating Works was built to offset, or com- plans were developed to meet the conditions and pensate for, the increased outflow capacity of the criteria specified in the IJC's 1914 Order. The water level of Lake Superior was the main factor considered Plan 1977 also specifies a minimum allowable in determining the outflows of Lake superior. flow in the St. Marys River. This requirement was The IJC, in its 1976 report to the U.S. and Canadian designed to prevent excessively low river levels Governments, noted that regulating the levels of downstream. It also ensures water for power Lake Superior would provide benefits throughout the production, and maintains adequate flows in the Great Lakes system if the regulation took the levels St. Marys Rapids for fish habitat. In addition. of Lakes Michigan-Huron into account. The first wmfer Aows are limited to a specified maximum to plan to incorporate this new concept of systemic hdp prevent ice jams in the river. regulation was Plan SO-901, which was later im- Each month, the Lake Superior Board assesses proved and given the name Plan 1977. Plan 1977 the factors that affect lake levels on Lake Superior came into effect following the issuing of the IJC and Lakes Michigan-Huron before setting outflows 1979 Order of Approval. according to Regulation Plan 1977. Water available Simply put, Plan 1977 works like this: If Lake for hydropower generation is shared equally between Superior's level is much higher than its average and Canada and the United States. Lakes Michigan-Huron are slightly above average, During winter operations, ice management becomes the outflow from Lake Superior will be increased to an important factor in regulating the outflows. ease its high water level condition. If Lake Superior Under the present operational procedure in Plan is very much below average and Lakes Michigan- 1977, the flow is held constant over the five winter Huron are slightly below average, the outflow from months (December through April). This is due, in Lake Superior will be reduced in order to raise its part, to the difficulty of moving gates in the level. Similarly, if more extreme water level condi- Compensating Works during the winter and the need tions exist on Lakes Michigan-Huron when compared to keep flows as uniform as possible for ice manage- with Lake Superior, the flows will be adjusted ment. Each winter, the U.S. Army Corps of Engneers accordingly to ease the conditions on the down- installs an ice boom in the lower St. Marys River to stream lakes. This water level balancing technique is maintain ferry service between Sugar Island and the the prindpal tool of systemic regulation. U.S. mainland. The boom also serves to reduce ice

Lake Supenor Compensating Wrb jams, which could be detrimental to Soo Harbor and than the historical range, this proved to be impos- the hydropower facilities. sible when record high and low water supplies oc- curred in later years. During the early 1950s the 4.4 Experience in Lake Superior Regulation maximum level as prescribed in the 1914 Order (602 The presence of Lake Superior regulation facilities feet or 183.5 metres) was exceeded. From thc M- does not mean that full control of lake levels is 1950s through the late 1960s water I& were an possible. This is because the major factors fiecting many occasions below the minimum leddkd kx the water supply to the Great Lakes - over-lake in the 1914 Order (600.5 feet or 183.0 -5). precipitation, evaporation and runoff - cannot be In the mid-1960s, low water levels were even more controlled; neither can they be accurately predicted severe on Lakes Michigan-Huron. To help alwate over the long term. With the advent of Lake Superior the situation on these lakes, outflows from I.,& regulation in 1921, humans have altered somewhat Superior in excess of those called for by the regu- the amount of water that flows in the St. Marys River lation plan were discharged. Due to extremely low from that which would have occurred under natural water supplies, however, only minimal assistance channel conditions. But, it is important to note that could be provided. the impact of regulation is small compared to the In the early 1970s high water supplies again natural factors which affect lake levels. occurred. Because of critically high water levels on While one objective of the 1914 order was to main- Lakes Michigan-Huroa, St. Cl& and Erie, the IJC tain Lake Superior levels within a more narrow range ordered reduced oudbs hna Ldre Superior. This

Impact oJrke 1985 Emergency Actions on Lake Supenor and Lakes Mic/7i,oan-Huron. emergency action provided nominal relief to the lower the regulation of Lake Ontario outflows. Its present lakes while still maintaining Lake Superior below eight members are from the Corps of Engineers, the level of 602 feet (183.5 metres). Transport Canada, Environment Canada, and five In the spring of 1985, the IJC again reduced the other state, provincial and local agencies and outflows of Lake Superior below those specified by representatives. Regulation Plan 1977 to help alleviate high water One of the primary conditions in the IJC order was level problems on Lakes Michigan-Huron and down- that Lake Ontario be regulated within a target range stream. However. after four months it was necessary of 242.8 and 246.8 feet (74.0 and 75.2 metres), to reverse this procedure and increase Lake Superior's respectively. Recognizing that future water supplies outflows when high precipitation on the Lake to Lake Ontario would at times be higher or lower Superior basin caused that lake to climb to a record than those experienced in the past, the IJC included high level. By mid-October, the IJC had increased an emergency provision. Criterion (k) of the order the flow to 133,000 cubic feet (3,770 cubic metres) specifies that, in the event that supplies exceed per second, the largest outflow on record. Neverthe- supplies of the past, the works in the international less, continued heavy rains over the Lake Superior rapids section should be operated to provide all pos- basin made it impossible to prevent Lake Superior sible relief to the riparian owners upstream and from slightly exceeding the level of 602 feet downstream. In the event that supplies less than (183.5 metres) for the months of October and the supplies of the past occur, the works should be November 1985. operated to provide all possible relief to navigation The maximum effect of the 1985 emergency action and power interests. This criterion has been followed was realized on Lake Superior in late August of that on several occasions to deal with extreme water year when that lake was raised 4.4 inches (11.2 supplies to Lake Ontario. cm) . Levels of Lakes Michigan-Huron, also by the 5.2 Regulatory Facilities end of August, were reduced 3.0 inches (7.6 cm). The outflows of Lake Ontario have been regulated Lakes St. Clair and Erie realized their maximum since 1960, following completion of the St. Lawrence benefit at the end of August and October, respect- Seaway and Power Project. The project required ivcly. The maximum reduction was 1.8 inches (4.6 extensive river deepening and construction of navi- a}for Lake St. Clair and 1.3 inches (3.3 cm) for gation locks. The Moses-Saunders power dawthat bke Erie. crosses the St. Lawrence River between ~dl, 5. LAKE ONTARIO REGULATION Ontario and Massena, New York is the prklpd regulatory structure. A second dam, locaed ~ea 5.1 IJC Orders of Approval Long Sault, Ontario, acts as a spillway when cut- Ir 1952, the IJC issued an Order of Approval to the flows from Lake Ontario are larger than the capacity a-ations from Canada and the United States to of the power dam. A third structure at , mstruct hydropower facilities in the international Ontario, can also be used to regulate the flow of reach of the St. Lawrence River, which extends from water, but is used principally to assist in the forma- Lake Ontario to Cornwall, Ontario and Massena, tion of a stable ice cover in the winter as well as to New York. The order gave Ontario Hydro the respon- prevent water levels from rising too high in Lake St. sibiity to construct and operate the Canadian portion Lawrence which is upstream of the power dam. of the hydropower facilities, while the New York The navigation locks in the Canadian portion of Power Authority was made responsible for the hyclro- the St. Lawrence Seaway are operated by the St. power facilities in the United States. In 1956, during Lawrence Seaway Authority. Locks in the United construction of the project, the IJC amended its order States are operated by the St. Lawrence Seaway to include regulation criteria designed to reduce the Development Corporation. Similar to the lock facili- range of levels experienced on Lake Ontario, facilitate ties on the St. Marys River, operations of these navigation in the St. Lawrence River, and provide facilities are federally controlled and not under the protection for riparian and other interests down- supervision of the IJC. Other hydropower and navi- stream in the Province of Quebec. gation facilities exist downstream of the power dam, In addition, the order established the International in the Province of Quebec. St. Lawrence River Board of Control to ensure com- pliance with the provisions of the Orders by the 5.3 Lake Ontario Regulation Plans and operators of these works. Upon completion of the Their Operations project in 1960, the St. Lawrence River Board took Three plans have been used to regulate the outflows on its duties and is presently the operating board in of Lake Ontario. All of these plans were designed to Luke Ontario Regu/atoly Works

F' CoTEW / @ Control works cj

8 flow- J% I Lake St. Francis

Power and Navipation Facilities in the Province oJQuebec v 10 meet the objectives specified in the 1952 Order and During winter operations, ice becomes an important the 1956 Supplementary Order of Approval. Plan factor in regulating Lake Ontario outflows. For a 1958-D, the present regulation plan, has a family of short period at the beginning of the winter, outflows operating curves for different trends in the water from Lake Ontario are often temporarily reduced to supply conditions for Lake Ontario. If the water assist in the formation of a stable ice cover at the supplies to the lake are high, for example, the curve outlet of Lake St. Francis (at the Beauharnois-Des with a higher supply indicator will be used to deter- Cedres hydropower complex upstream of Montreal) mine the outflows, and vice versa. This was designed and in the international rapids section of the St. to maintain the levels on Lake Ontario within the Lawrence River upstream of Cornwall, Ontario and target range of 242.8 and 246.8 feet (74.0 and Massena, New York. Ice booms are also located at 75.2 metres), respectively. several sites in the river to help this process. A Plan 1958-D also specifies a number of flow limi- breakup of the ice cover can cause an ice jam and tations. For example, monthly minimum permissible result in severe difficulties in flow regulation and flows are specified to ensure adequate flows for hydropower production. After a stable ice cover is hydropower production. However, another limitation formed, flows in the river are gradually increased to restricts the flows in the river when Lake Ontario's offset any temporary flow reductions. water level is low. The latter restriction is designed Operational experience has shown that flooding in to ensure adequate depth in the St. Lawrence River. Montreal area by spring runoff from the Ottawa While Lake Superior's outflow is adjusted monthly, River (a major tributary to the St. Lawrence River) Lake Ontario's outflow is adjusted weekly by the can be reduced by temporary reductions in Lake St. Lawrence River Board according to Regulation Ontario outflows. These reductions are later offset Plan 1958-D. This is done for two reasons. First, Lake following the freshet. Ontario is much smaller than Lake Superior, and thus its levels respond more quickly to changes in 5.4 Experience in Lake Ontario Regulation water supples to the lake. Secondly, inflows to Lake As with Lake Superior, regulation of Lake Ontario Ontario, ma& up mainly by outflows from Lake Erie, does not ensure full control of the levels of the lake, ax mi& lmgher than the inflows to Lake Superior. because the major factors affecting the water supply

Moses/Saunders Powerhouse, CornwaN, Ontano/Massena, New York feet LAKE ONTARIO ELEVATION (IGLD, 1955) metrea 246 - pEEq - 750 . 245 - - 74.5 244 -

243 - - 740

242 - - 738 - 7 - 6 241 1"""11'1 IlII1III1III1lIIIII:735 JFMAMJJASONDJFMAMJJASONDJFMAMJJA 1963 1964 1965 LAKE ONTARIO WITH AND WITHOUT REGULATION feet metres

- 75.6 - 5 - 4 - 3

- 74 5 244 - - 4 - 3

IIIIIIIIIII l111111111111111111 JFMAMJJASONDJFMAMJJASONDJFMAMJJA 1986 1987 1988 I Impact of Lake Ontario Regulation to the Great Lakes - over-lake precipitation, evap- in the St. Lawrence River that winter helped to make oration and runoff - can not be controlled, nor can these high flows possible. During that time, water they be accurately predkted over she lo~gm. level co~~in the Montreal area and downstream Further, the fluctuation of Lake Ontario beb cap memonitmed dose4y so as to not aggravate the not affect the upstream lakes due to the p-esence oC existing high water conditions. Niagara Falls. Nonetheless, Lake Ontario regulation High flows in the St. Lawrence River have been since 1960 has had some impxts. made possible with the completion of the Seaway During the extreme tow water period of the mid- and Fuwer Project. But high flows increase cross 1960s Lake Ontario levels were maimiied slightly currents and water velocity, which in turn can make higher than they otherwise 'WPUld haw! been withaut navigation cllfficult. At times, these c~tioionstem- regulation. In the early and mid-1970s. when water porarily Rdt traffic. supplies were critically ~gh,water hkwere held In the Spring of 1989, the Baard reduced Lake to more than a foot (0.3 metre) below pre-project Ontario's owbws because of a concern that its levels. Despite this action, and because ol uwtewk had faksignifmntty below its seasonal high water supplies, Lake Ontario water levels reacbed Long-term awagc There \~;;tsalso the cmern 247.9 feet (75.6 metres), well &ve the range p- about low levels in tk international section of the scribed in the IJC's Order of Approval. river. The bwreduction was carried cut during the In the winter of 1986-87, the IJCincreased Lake spring runoff, so so to not adversely Ontario's outflows above those prescrfied by Plan afTect downsueam interests. An unexpected heavy 1958-D. This action prevented Lake Ontario from spring rainhi!, codidwith the reduced outflows. rising to extreme high levels due to continued extreme caused the kvel of Ldie Ontario to rise sharply, high inflows to the lake from the upper Great Lakes. and thus enabled a return to plan flows earlier than The very mild weather and favourable ice conditions anticipated. 6. WHO YOU CAN CONTACT ABOUT LAKE REGULATION Several organizations focus some or all of their work on Great Lakes levels and outflow regulation. If you have comments or questions about the regulation of Lake Ontario or Lake Superior, contact the following offices. In Canada In United States

Secretary, Canadian Section Secretary, United States Section International Lake Superior Board of Control International Lake Superior Board of Control, and Environment Canada Secretary, United States Section 111 Water Street, East International St. Lawrence River Board of Control Cornwall, Ontario K6H 6S2 U.S. Army Corps of Engineers Telephone: (613) 938 5725 North Central Division 536 South Clark Street Secretary, Canadian Section Chicago, Illinois 60605-1592 lnternational St. Lawrence River Board of Control Elephone: (312) 353 6355 Transport Canada 6th floor, Canada Building U.S. Army Corps of Engineers 344 Slater Street P.O. Box 1027 Ottawa, Ontario KIA ON7 Elephone: (613) 990 5619 477 Michigan Avenue Detroit, Michigan 48226 Great Lakes Water Level Communications Centre Elephone: (313) 226 6440 Environment Canada P.O. Box 5050 U.S. Army Corps of Engineers 867 Lakeshore Road 1776 Niagara Street Burlington, Ontario L7R 4A6 Buffalo, New York 14207-3199 Rlephone: (416) 336 4581 Elephone: (716j 879 4257

Ministere de I'Environnement du Quebec lnternational Joint Commission Direction de l'hydraulique United States Section 2360 chemin Sainte-Foy 2001 S Street, N.W. Sainte-Foy, Quebec GIX 4H2 Washington, D.C. 20440 Telephone: (418) 644 3430 Rlephone: (202) 673 6222

lnternational Joint Commission Canadian Section 100 Metcalfe Street, 18th floor Ottawa, Ontario KIP 5M1 Elephone: (613) 995 2984

(Disponible en franqais) Environnement Canada Canada