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 Lakes-St. Lawrence River System . 4. Lake 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 Ontario 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 Canada, 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 Great Lakes-St. Lawrence River System is offices in Washington, D.C. and in Ottawa and one oP North America'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 Lake Ontario. 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 Boundary Waters 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 United States 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. Lake Superior, at the top of this chain, and Hou regulation. T"flows into Lake Huron through the St. Marys Llhe Superior's water level fluctuates somewhat Rim. Water also flows out of Lake Michigan 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 Lake Michigan 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 drainage basin 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 Detroit River to Lake Erie. lake's surface area, and thus land runoff contributes Ldre Erie flows into Lake Ontario via the Niagara 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 Miles 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.