BOTANICAL EVALUATION OF THE GOAT ISLAND COMPLEX, NIAGARA FALLS, NEW YORK
P. M. Eckel
Buffalo Museum of Science
1020 Humboldt Pkwy
Buffalo, NY 14211 U.S.A.
www.buffalomuseumofscience.org

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HYDROLOGY
Since the study area is defined by the water forming its boundaries, and its interest lies in the fact of its association with a series of great cataracts with their contribution to atmospheric moisture, water has much to do with past and present biological systems at Niagara. River water potentially has the effect of dissolution and leaching of the surfaces over which it passes, and of carrying within it nutrients, the residues of dissolving and leaching, as well as pollutants and other wastes which are dumped into it. It becomes enriched by aeration or oxygenation after its passage over the falls and rapids as it settles over the surrounding landscape.

The Niagara River is part of the Great Lakes Watershed system, which drains from rivers emptying into Lake Superior in the west to the Atlantic Ocean in the east. The lakes had a total water volume of 6,000 cubic miles at the end of the nineteenth century (6 Ann Rep Comm, 1890). The volume of flow in the Niagara River is related to the net natural runoff of the lake basins upstream - an area of around 260,400 square miles above the Niagara River (NREP, 1972).

The area of the river between Grand and Navy Islands to the Cascades at the east end of Goat Island is called the Chippawa-Grass Island Pool. From this section of the river most of the water for hydro-electric power is diverted.

At Goat Island's eastern end the river divides into a north and a south channel and proceeds to a drop of about 180 feet to the western end of Goat Island. The cataracts formed at the brink of this drop are three: the Horseshoe, or Canadian Falls (nearly the entire brink is located in Canadian territory - the international border a stone's throw off Terrapin Point) which is 2,200 feet, The American, 1,060 feet, and the Bridal Veil Falls, 15 feet wide. The Horseshoe Falls is eight feet lower in height than the American.

The volume of water carried by the Horseshoe Falls is eight times that of the American (NREP, 1972), with correspondingly greater erosive power, and ability to charge the atmosphere with water. In the three-year period of 1925, 1926 and 1927 it was determined that the flow of water over the American Falls was only four percent of the total flowing out from the Grass Island Pool. Since 1925 "there has been a 24 percent increase in the flow of the American Channel" (The American Falls International Board, 1971), due to control structures built in the Grass Island Pool section of the river, and cessation of diversion of the Schoellkopf and Adams Hydroelectric Plants. Krajewski and Liberty (1981) report that the Horseshoe Falls "carries 90% of the water presently available."

The waters at the cataracts are very shallow, especially after diversion. Prior to the major diversions of 1956 and 1962, water in the center of the Horseshoe falls was about 10 feet. Now it is 2 feet on average (Tiplin, 1988). Water depth at the rock ridge at the head of the American channel is around three feet (The American Falls International Board, 1971).

The flow or volume of water in the Niagara River "reflects the effects of all diversions into or out of the upper Great Lakes. The storage area of the lakes involved and the discharge capacity of their outlet channels fix the magnitude and timing of the effect ..." on river flow (The American Falls International Board, 1971). Diversions of the waters of the Great Lakes system include those of the Ogoki River between the Great Lakes and Hudson Bay drainage, Longlac, Chicago Sanitary District Canal, the Welland Canal and the New York State Barge Canals (The American Falls International Board, 1971).

Many speculations have been made in the geological literature during the past century regarding the loss of water to flow over the falls of Niagara. James Hall, New York State Geologist, in 1843, made the prediction that "the mighty Niagara is destined to be, at certain seasons, but a diminutive representative of its former grandeur" not because of water diversion for hydroelectric purposes but due to the loss of the regional primeval forests still extant in the early nineteenth century in the Lake Superior region, and that the loss of this vegetation "opening ... the surface to the influence of the sun's rays will greatly diminish the supply of water flowing into its tributaries. These causes will sensibly diminish the quantity passing down the natural outlet ..." to be witnessed at Niagara.

The amount of water flowing in the little channel between Goat Island and the first of the Three Sisters Islands just south of it in the Canadian or southern channel of the river may be seen as some indication of lowered water levels in the Great Lakes by 1898. Some diversion for hydraulic purposes in the Niagara River had occurred by that time, but was apparently not considered to have a significant impact on local water levels. Although prior to 1850 there was a great sheet of water in this channel, by 1899 the channel had to be dynamited to produce a reasonable flow approximating earlier conditions (16 Ann Rep Comm, 1900; see section on the First Sister Island).

The first board of Commissioners, especially Andrew Haswell Green, recognized this dependence of Niagara Falls on water-use policy upstream, such that "the Commissioners deem it advisable that the National government be requested to appoint a commission to confer with a Canadian commission as to the means to be devised to prevent any excessive diversion of the waters of the Great Lakes, and to consider the whole subject of the uses and control of these waters, and to report its conclusions to Congress, with such recommendations as it may desire to submit" (15 Ann Rep Comm, 1899). The result of this action was legislation leading to the creation the International Joint Commission.

For general purposes the volume of water on average in the river is presently 202,000 cubic feet per second (Tesmer, 1981). Presumably this is the prediversion figure one might assume was the case throughout the last century, and also that it includes diversion rates of facilities taking water in the upper river other than the Robert Moses Power Authority and the Sir Adam Beck Power Generating Facility. The natural volume of water is the largest in North America for a river 33 miles long (NREP, 1972).

A hydraulic canal for diverting water for industrial purposes was built in 1857 in the city of Niagara Falls (Tiplin, 1988) which "Caleb S. Woodhull, Horace Day and others had dug and struggled unsuccessfully to make profitable" and later sold at a "sheriff's sale" (Mizer, 1981). Jacob F. Schoellkopf bought it for $71,000 in 1877. Other diversions, such as to serve the domestic water needs of the adjoining cities probably occurred at an earlier date.

A second tunnel for the diversion of water was under consideration in 1890, and eventually built by 1892 (by the Niagara Falls Power Company, Mizer, 1981): "in 1868 the volume of water passing over the falls measured by the corps of the US army was from 273,329 to 280,757 cubic feet per second - the tunnel being constructed meant to divert 10,000 cubic feet per second (Bogart, J. State Engineer and Surveyor, 1890, in the 7 Ann Rep Comm, 1891)

The Schoelkopf Power Plant on the American side was built from 1897 to 1925 and in operation till 1956; the Niagara Falls Park and River Railway Power House was built in 1892; the Canadian Niagara Power Generating Station began operating in 1905; the Ontario Power Generating Station in the early 1900's, the Toronto Power Generating Station (date unavailable); the Sir Adam Beck Generating Stations from 1922 and the Robert Moses Niagara Power Plant from 1961 (Tiplin, 1988). For the diversion-rate data of these facilities see The American Falls International Board, 1971. This power-generating capacity transformed the lives of people in western New York and Ontario.

In 1912, "existing diversions have already seriously interfered with and injured the scenic grandeur of Niagara Falls at the Horseshoe, which injury and interference will be emphasized by the effects of lower stages sure to recur on Lake Erie and the upper lakes due to natural causes" (W. L. Marshall, Chief of Engineers, U. S. Army, War Department for Maj. Charles Keller, Corps of Engineers, in 28 Ann Rep Comm, 1912). Mr. Marshall also suggested the remedy was to place a "submerged dam placed in the bed of the river immediately above Horseshoe Fall, with the object of diverting a portion of the great volume passing over the center ... so as to increase the streams feeding the depleted ends of that fall ..." Major Keller was willing to discuss "the possibility of further concessions to the power companies." Perhaps it is these recommendations that fueled the half century of river-bed modifications to "beautify" the impoverished cataracts.

At present, fifty percent of the water in the Niagara River is removed for the purposes of generating power, etc. between April first and October 31 (tourist season); seventy-five percent is removed during the winter (non tourist) months (Bastedo in Tesmer, 1981).

When the water is high in the Great Lakes, as after heavy rains in the system, more water appears to flow around the islands, inundating low areas, such as at the western extremity of the Third Sister Island (personal observation, 1987). Also if there is a south-western wind across Lake Erie, especially during winter storms, a greater than normal mass of water may flow into the Niagara River raising its level temporarily, although the intensity of this phenomenon may be regulated by the present water diversion device in place above the Horseshoe Falls. Reduction in flow in winter, and its elevation in summer due to diversion manipulations all affect the rates of erosion and water availability at the islands.

The gorge of the Niagara River has been extending itself continuously from the moment the cascade began at what are now called the villages of Lewiston, New York and Queenston, Ontario.It has been eroding generally southward for over 9000 years. "The process of recession of the Falls has been quite rapid in geologic time, and even in terms of a human lifetime. The Falls reached Goat Island and separated into two about 600 years ago. Since that time, although the American Falls has receded very little (about 200 feet), the Horseshoe has retreated some 2,500 feet" (Otis, 1982)."

Goat and Luna Islands, then, developed the present rocky bluffs or escarpments on their western ends as recently as seven hundred years ago, whereas in the previous millenia, the level of shoreline presently bounding their other three sides also bounded the fourth. This will have implications for ease of accessibility of animals and aboriginal peoples to the island complex through time, and suggests the original forest at the western crest of Goat Island may have been a shoreline remnant, similar in origin to the crest forests all along the gorge of the river below the cataracts.

It is estimated that the Falls (presumably the Horseshoe Falls where the main channel lies) retreats one to two feet annually (Tesmer, 1981) from the force of the water presently allowed to fall over it. Recession at the Horseshoe Falls was intensified from the effects of early water diversion activities, which tended to concentrate the volume of river water in the center of the Horseshoe Falls (Tiplin, 1988). To compensate for this concentration, a submerged weir was built in 1942 to raise the level of water in the Grass Island Pool. The conspicuous, unsubmerged International Control Structure, built in 1953-54 to spread the remaining water allowed over the cataracts more or less evenly over the Horseshoe and American Falls, was accompanied by "remedial work" at the exposed edges of the Horseshoe Falls -including the Terrapin Point section on Goat Island. Remedial work included excavating deeper channels in certain areas above the falls. "Viewing areas" were areas of reclaimed land, shortening the width of the falls at Terrapin Point, on Goat Island and the Table Rock viewing area in Ontario. On Goat Island, a coffer dam was built just upriver from Terrapin Point. The coffer dam "dried off the river bed so that the area around Terrapin Point could be filled in" (Tiplin, 1988). The old area where the bridge to the Terrapin Tower was built was then graded and seeded to grass.

The jointed bedrock beneath the islands provides avenues for water seepage. The horizontal migration of ground water through joints along the bedding planes of the dolomite bedrock probably accounts for some or all of the seepage visible on Goat Island, such as the old Spring on the northeastern side and the three little seeps on the southeast side of the island facing the upper end of the First Sister. The soil along the elevations of the north side of Goat Island is moist and in places quite saturated. A series of culverts of various sizes and ages are located here, in the bank of soil, and one at the level of the river, which provide outlets for water runoff from a variety of sources, some perhaps draining storm sewers, and runoff from the grading required for the circumferential roadways, viewmobile path and pedestrian paths.

Three small, open seeps occur on Goat Island just opposite the east end of the First Sister, together with a culvert at water lever among Willow trees. A drain is located in the picnic area near the entrance to the Three Sisters, probably associated with road drainage. It is my understanding that deposition of ballast at the east end or upstream extension of Goat Island constructed in 1959-60 (The American Falls International Board, 1971), has altered the pattern of subsurface drainage or surface seepage (staff communication) by the force of current through the rock-fill, but I was unable to investigate the significance of this. How much of the soil hydrology evident today is due to human modification, such as road gradings, sewage facilities for buildings at the west end of the Island, drainage of extensive low areas, etc., could not be established at this time.

The deep and loose sediments overlying the bedrock on Goat Island, in addition to the dense vegetation of the primeval situation which existed at the Reservation's establishment in 1885, would have served as sinks for water entering the ecosystem through horizontal migration of river water through bedrock. This seepage may have contributed to the effect of quicksands said to exist in the lower sedimentary layers, and springs and seeps on the island, the relatively continual addition of spray from the Horseshoe Falls, and rain, snow and ice accumulations in winter.

The general wetness of the environment, especially the upper sediments made it very difficult to maintain the surface of the early road system on the island. Ceramic drain tiles were put in place during the early years of the Reservation to dry out the first gravel roads, but for years the island's caretakers lamented the high moisture beneath the forest canopy and took steps to eliminate it. Drainage modifications persisted throughout the early decades of the twentieth century whenever new structures were put in place. At times prior to 1885, attempts to modify drainage, for example, at the publicly used spring of potable water on the north shore of Goat Island, may account for the absence of likely wet habitats for hygrophytic species of plants, such as those reported by David Douglas in 1823 - Skunk Cabbage (Symplocarpus foetidus) for example which grows in springy situations on the Ontario side of the falls (see section on collectors), but observed by no one subsequently. Tile drains were still being built in 1912 when the paths at the entrance to Goat Island were felt to be in poor condition due to high soil moisture. Rains continued to cause washouts and landslides, disturbing the roads and paths (29 Ann Rep Comm, 1913).

In the Evershed map of Goat Island of 1883, a swamp is indicated on the north east side of the island around where The Spring was located. The swamp was in the river margin, and is reminiscent of that drawn for the western extremity of the Second Sister Island. This swamp on the north side of Goat Island may have vanished by modification, as suggested above, or by lowering of the river volume as water levels in the Great Lakes lowered through diversion and stripping of the native forests in the upstream Great Lakes Watershed region throughout the nineteenth century and intensified local diversion for hydroelectric production in the present century.

The "drying up" of The Spring itself may be due to decreased water pressure in joints presumed to feed it in the Goat Island bedrock as water volume in the river decreased.

Low areas of poor drainage supporting wet vegetation, such as the two swampy areas just mentioned are the product of lowering of the volume in the Niagara River, mentioned by Kindle and Taylor on their geological map of the area (1913), before European settlement of North America. These areas of poor drainage on former river bed were much more extensive on the Canadian rim of the Niagara Gorge and area of the upper river at the cataracts, and supported one of the most interesting plant communities in the area.

It seems probable in prediversion times that a higher degree of water pressure in the joints of the bedrock beneath the Goat Island sediments prevailed, and river levels were higher with the result that there was to some degree more water coming up as mist due to shattering of more water on the rocks at the base of the Horseshoe and American Falls. It is reasonable to expect that there was a higher degree of soil moisture available to plant populations on Goat Island than exhibited today. The original, denser vegetation would also hold more atmospheric water, of which there was locally an excess due to mist from the falls, especially on the west end. A constant regular provision for moisture in the environment would approach a more optimal environment for plant growth that is one factor in the historic testimonials accounting for an unusual abundance of individual species in the Goat Island complex.

A higher degree of topographic irregularity, or topographic diversity, prior to establishment of the present extensive graded lawns and particularly asphalted pedestrian and vehicular surfaces, would have provided significantly more microhabitats with complex and elevated moisture regimes, more ecological niches for occupation by various species and hence be a factor in the development of the unusually high species diversity reported for the island a century ago, before New York State ownership began in 1885.

Conversely, removal of normal, natural water regimes in the Goat Island ecosystem has been a factor in depletion of both the historic botanical abundance and species diversity through desiccation. Thinning of trees and shrubs, as is the present policy, for example, weakens the forest's ability to remove moisture from the atmosphere, be a less effective block to sunlight and prevailing winds which evaporate moisture in natural habitats.