Canada and United States Preservation and Enhancement
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~ INTERNATIONAL JOINT COMMISSION CANADA AND UNITED STATES PRESERVATION AND ENHANCEMENT OF THE AMERICAN FALLS 1975 INTERNATIONAL JOINT COMMISSION CANADA AND UNITED STATES COMMISSIONERS MAXWELLCOHEN, HENRYP. SMITH111, Chairman Chairman BERNARD BEAUPR~CHARLES R. Ross KEITHA. HENRY VICTORI,. SMITH ADVISERS J. LLOYD MACCALLUMJOHN F. HENDRICKSON MURRAYW. THOMPSONSTEWART H. FONDA, JR. RICHARDM. BENNETTJAMES G. CHANDLER SECRETARIES DAVIDG. CHANCE WILLIAMA. BULLARD FORMER COMMISSIONERS WHO PARTICIPATED IN THE INQUIRY A. D. P. HEENEY EUGENEW. WEBER MATTHEWA. WELSH D. M. STEVENS CHRISTIANA. HERTER, JR. REN~DUPUIS A. D. SCOTT i N IAGARA FALLS CAN SEC !JC DRAWN W bJ Y OCT 12 Plate 1 TABLE OF CONTENTS Chapter Page I INTRODUCTION .. .. 1 TH E AMERICAN FALLS AMERICAN I1 THE 3 TI1 THE COMMISSION’S INQUIRY 9 IV THE INVESTIGATIONIV BOARD’S 11 V PUBLIC HEARINGS PUBLIC V .. 15 V I THE COMMISSION’STHE VI CONSIDERATIONS CONCLUSIONSAND 17 Alternatives for the Appearance Alternativesthe for AmericanofFalls the 17 Alternatives for Public Safety Public for Alternatives .. 20 VI1 RECOMMENDATIONS 28 APPENDIX Text of Reference Text of Letter Extending Referencc Membership of the Board and Working Committee Participating Agencies Persons Presenting Briefs or Submitting Statements LIST OF PLATES Plate Page 1 Map Fallsof Niagara . 11 2 Aerial View of NiagaraFalls . .. .. , . , . ,. 4 W inter SceneFalls 3 Winter American of the 5 S chematic Profile4 Schematic Fallsof American .. 6 A merican Falls Dewatered5 FallsAmerican ... .. ...... ... .. 12 6 Model of AmericanShowingFalls Present Talus Arrangement . 18 7 Model of AmericanFallsShowing Substantial Talus Removal .. .... .. 18 Photo Credits Title Page - Ontario Hydro Plate 2 - Power Authority of the State of New York ... 111 CHAPTER I INTRODUCTION The Niagara Falls have long been recognized as one of necessary topreserve or enhance the beauty ofthe the most spectacular natural phenomena in the world. AmericanFalls. Under such References the Commis- Theyare also asymbol of internationalamity and sionreports to both Governments on thefacts and cooperation between two nations sharing a vast water circumstances of matters referred to it and its recom- system. The United States and Canada as guardians of mendations in no way bind either Government. theFalls have formore than 100 yearsundertaken studies and taken steps to preserve their beauty. Indeed, Specifically, the Commission was asked to investigate the Governments of the United States and Canada have andrecommend measures that are feasible and desir- recognized and affirmed by treaty, first in the Boundary ableto remove the talus which has collected at the Waters Treaty of 1909 and later in the 1950 Niagara base of theAmerican Falls, and to retard or prevent Treaty,a primary obligation to preserve andenhance futureerosion. The Commission was also askedto the scenic beauty of the Niagara Falls. recommend other measures which may be desirable or necessary to preserve orenhance the beauty of the In thescTreaties the two Governmentsalso recog- AmericanFalls and the allocation of thework and nized a common interest in developing the hydroelectric costs of constructionbetween the UnitedStates and potential of theNiagara River. Tt is importantto Canada. The Commission was asked tobear in mind emphasize that the relationship between these two con- the obligations of Canada and the United States con- cernshas remained clear; both countries have com- tained in theNiagara Treaty of 1950and the mutual mitted themselves to the goal of preserving the Falls as interests of thetwo countries in refraining from mea- a natural wonder of international significance, while sures which might preserve or enhance one of the Falls at the same time utilizing its power for the benefit of to the detriment of the other. the citizens on both sides of the Boundary. By similar letters dated October 1 and 5, 1970, the This inquiry is a consequence of public concern that Governments of Canadaand the UnitedStates re- the accumulation of talus at the base of the American quested the Commission toextend its investigation Fallsmight make their appearance less appealing. beyondthe original terms of theReference so asto Three major rockfalls from the crest of the American includeaspects of public safety atthe flanks of the Fallsoccurred in JanuaryI93 I, July1954 and De- AmcricanFalls and at the GoatIsland flank of the ccmber1959 depositing some 130,000 cubic yards of Horseshoe Falls. The Commission wasiasked to deter- rock at thc foot of the American Falls, thus raising the mine if the immediate areas of the American Falls and height of the talus ovcr a largepart of theirwidth. of the Goat Island flank of the HorseshoeFalls were Thercarc now about 280,000 cubicyards of talus at endangered by erosion and other geological processes, the base of the American Falls. and if so, what measures are feasible and desirable in order to eliminatehazards to persons,property or to As a result of publicconcern, the United States Congress in 1965 authorized the Corps of Engineers to thc scenic beauty in the region. study the measures needed to preserve and enhance the Thecomplete text of the1967 Reference and the beauty of the Amcrican Falls. The results of this study 1970 extension are appendcd to this report. were madc available to the Commission. This report describes the physical setting of the Falls, The Commission’s involvement began on March 31, the activities of the Commission and its American Falls 1967, when the Governments of the United States and InternationalBoard during thc course of this inves- Canada, in accordance with Article IX of the Boundary tigation and the Commission’srationale for the con- WatersTrcaty of 1909, requested the Tnternational clusionsand recommendations that emerged. Joint Commission to investigate and report on measures CHAPTER I1 THE AMERICAN FALLS TheNiagara River flows northfrom Lake Erie to The attraction of the American Falls is not exclusive Lake Ontario for 33 miles. It forms the border between tothe summer months. In winterthe mist and spray western New York Statc and the Niagara Peninsula of convert the immediate area into a beautiful spectaclc of southernOntario. The total drop in theRiver is 326 ice and snow. Massive ice formations build up on the feet. The long term average flow of the River is 202,000 talus in front of its vertical face. An ice bridgc forms cubicfeet per second (cfs). The meanmonthly flows in theMaid-of-the-Mist Pool. Its mass constantly have varied from 116,000 to 274,000 cfs. changes due to the accumulation and rclease of icc. See Plate 3. The Niagara Falls are located 19 miles downstream from Lake Erie. Goat Island divides the River into two Originallythe Falls were located at the Niagara channels. It separates Niagara Falls into the Horseshoe Escarpment. They have retreated seven miles upstream Falls on the Canadian side of the River and the Ame- throughnatural erosion in the last 12,000 years. This rican Falls on the United States side. The vertical drop is equivalent to five feetper year. About 700 years between the crest of the Falls and the Maid-of-the-Mist ago the receding Falls reached and passed Goat Island, Pool is 167 feet. Although far from the highest in the thus creating the American Falls. Since separating, the world, the Niagara Falls with their impressive breadth, Horseshoe Falls have carved their way nearly 3,000 feet theirimmense volume of waterand their thundering upstream, while the American Falls have receded only sound provide a spectacle of awe-inspiring grandeur for slightly from the gorge walls which were produced by over tcn million visitors annually. thecutting action of themain Falls. If therecession of theHorseshoe Falls continues at the present rate, TheAmerican Falls have a crest length of 1100 they will interceptthe American Channel above Goat feet. Except for some irregularities caused by rockfalls, Island in about 2,000 years and permanently dewater a relatively uniform sheet of water falls over the crest. the American Falls. Luna Island located in the crest separates the smaller cataract, Bridal Veil Falls, from the main cataract. The Erosion and rockfalls are a natural process by which waterplunges about 100 feetonto the accumulated slopesbecome more stable. The strength of therock, talus and then violently cascades into the Maid-of-the- the nature of the rock defects, the horizontal and hydro- Mist Pool. static pressures and the absence or presence of a talus buttress, all affect the stability of a cliff. The top layer Abouta half-mile upstreamfrom the Falls is an of thebedrock at the American Falls is composed of IS-gatecontrol structure between the Canadian shore hard,erosion-resistant Lockport dolomite, about SO andTower Island. The structure maintains the water feetthick. Beneath this caprock is approximately 60 levels of Grass Island Pool while permitting the diver- feet of softerRochester shale. This is underlain by sions of water from the Pool for the power production variousinterbedded layers of limestones,dolomites, allowed by the 1950 Niagara Treaty. The intakes to the sandstonesand shales. Theenormous force of falling diversiontunnels leading to the Ontario Hydro power water erodes the softer, less resistant shales and sand- generatingplant are a third of a mileupstream from stones beneath, thus undermining the dolomite cap rock thc controlstructure; those leading tothe Power on thecrest. Ultimately the cap rock and shale may Authority of the State of New York plant are two miles failtogether, or the caprock itself mayfail when upstream. The control structure also assures an average undermined. See Plate 4. flow of 10,000 cfs intothe smaller channel along the United States shoreline. The water in this channel drops The flow at the Horseshoe Falls has been sufficient to fifty feetover a series of rockledges andscattered scourout a basinabout 200 feetbeneath the water boulders to the crest of the American Falls. Numerous surfaceat its base.The fallen rock is abradedinto islands subdividethe American Channel into several particlesand transported downstream. This process smaller channels. Sec Plate 2. preventsany visible talusaccumulation.