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Suggested Citation:"OVERVIEW." National Research Council. 1989. Great Lakes Water Levels: Shoreline Dilemmas : Report on a Colloquium. Washington, DC: The National Academies Press. doi: 10.17226/18405.
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Suggested Citation:"OVERVIEW." National Research Council. 1989. Great Lakes Water Levels: Shoreline Dilemmas : Report on a Colloquium. Washington, DC: The National Academies Press. doi: 10.17226/18405.
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Suggested Citation:"OVERVIEW." National Research Council. 1989. Great Lakes Water Levels: Shoreline Dilemmas : Report on a Colloquium. Washington, DC: The National Academies Press. doi: 10.17226/18405.
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Suggested Citation:"OVERVIEW." National Research Council. 1989. Great Lakes Water Levels: Shoreline Dilemmas : Report on a Colloquium. Washington, DC: The National Academies Press. doi: 10.17226/18405.
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Suggested Citation:"OVERVIEW." National Research Council. 1989. Great Lakes Water Levels: Shoreline Dilemmas : Report on a Colloquium. Washington, DC: The National Academies Press. doi: 10.17226/18405.
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Suggested Citation:"OVERVIEW." National Research Council. 1989. Great Lakes Water Levels: Shoreline Dilemmas : Report on a Colloquium. Washington, DC: The National Academies Press. doi: 10.17226/18405.
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Suggested Citation:"OVERVIEW." National Research Council. 1989. Great Lakes Water Levels: Shoreline Dilemmas : Report on a Colloquium. Washington, DC: The National Academies Press. doi: 10.17226/18405.
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Suggested Citation:"OVERVIEW." National Research Council. 1989. Great Lakes Water Levels: Shoreline Dilemmas : Report on a Colloquium. Washington, DC: The National Academies Press. doi: 10.17226/18405.
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Suggested Citation:"OVERVIEW." National Research Council. 1989. Great Lakes Water Levels: Shoreline Dilemmas : Report on a Colloquium. Washington, DC: The National Academies Press. doi: 10.17226/18405.
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Suggested Citation:"OVERVIEW." National Research Council. 1989. Great Lakes Water Levels: Shoreline Dilemmas : Report on a Colloquium. Washington, DC: The National Academies Press. doi: 10.17226/18405.
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Suggested Citation:"OVERVIEW." National Research Council. 1989. Great Lakes Water Levels: Shoreline Dilemmas : Report on a Colloquium. Washington, DC: The National Academies Press. doi: 10.17226/18405.
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Suggested Citation:"OVERVIEW." National Research Council. 1989. Great Lakes Water Levels: Shoreline Dilemmas : Report on a Colloquium. Washington, DC: The National Academies Press. doi: 10.17226/18405.
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Overview The Great Lakes—Superior, Michigan, Huron, Erie, and On- tario, together with Lake St. Glair and connecting waterways— constitute a resource of uncommon beauty and value. Having existed scarcely 3,000 years in their present form, these artifacts of the last Ice Age now hold 20 percent of the world's fresh water. While the drainage area is modest compared to the vast expanses of water sur- face, some 40 million people occupy the catchment, including about one-third of the entire population of Canada. Major industrial and commercial centers dot the shores: Milwaukee, Chicago, Detroit, Cleveland, Buffalo, and Toronto, among others. It would be diffi- cult to exaggerate the importance of these lakes to the human and physical environment of the United States or Canada. The Great Lakes have many uses. Millions of people fish, boat, and swim in their waters. They provide a water transportation route from the Atlantic Ocean to the heart of the continent. Hydroelectric power is generated by exploiting the 180-m elevation difference from Lake Superior to the Gulf of St. Lawrence, and nuclear and fossil- fueled power plants draw cooling water from the lakes. Industrial ac- tivities of every description and cities of all sizes rim the shores of all five lakes, withdrawing water and discharging wastes. Recreational facilities, hospitals and universities, estates, farms, housing develop- ments, and simple vacation cottages compete with beach grass and marsh for a place at the water's edge. Still, the lakes retain much of

2 GREAT LAKES WATER LEVELS their natural beauty. Biological communities, although often under stress, largely have survived the intense human activity, and in some instances have recovered after decades of degradation. But lakes must have shores and shores are, by their nature, in a constant state of change. Dunes migrate across flat areas, beaches wax and wane, bluffs are steadily undercut and eroded. A recent study estimated the mean rate of shoreline erosion for the Great Lakes as a whole at 0.7 m/yr, nearly identical to that for the Atlantic Coast (0.8 m/yr) or the Chesapeake Bay (0.7 m/yr) (May et al., 1983). Lacking the lunar tides or the frequent powerful storms of the ocean coasts, however, lake shores respond to a different set of hydrologic phenomena. Of particular interest is the effect of deviations in net basin sup- ply (NBS), defined as direct rainfall plus runoff and net groundwater inflow, less lake evaporation. The Great Lakes are connected by a series of narrow channels that operate at relatively uniform flow. Transient changes in NBS, therefore, lead to more persistent changes in lake levels. Since the Algama period, when the lakes assumed their present configuration, mean annual lake levels may have fluctuated through a range of as much as 4 m (Larsen, 1985). During the past 125 years, the maximum range of variation has been only 1.7 m (for the Michigan-Huron system). A total of five major diversions to and from the lakes have been implemented in that period, but they have had a small effect on lake levels (generally less than 0.1 m). Added to the long-term changes in mean annual lake level are the short-term consequences of seasonal and episodic weather variation. Seasonal changes in precipitation and evaporation cause water levels to vary by as much as 0.5 m in a given year, while prolonged winds have been known to drive the water surface to as much as 2.4 m above mean level (e.g., in Lake Erie on December 2, 1985; Quinn, this volume). Storms occur in the Great Lakes, of course, and they are sometimes accompanied by water level surges and high-energy erosive wave action. Since the indigenous biota as well as human activities generally have adjusted to long-term average water levels, episodes of high or low water have been associated with periods of damage and dis- ruption. Low water levels dry out wetlands, expose large areas of mudflats, and disrupt fish spawning. Recreational access and water transportation are hampered, and hydroelectric output is reduced.

OVERVIEW 3 Conversely, high water inundates beaches, floods low areas, and ac- celerates shoreline erosion. Damages associated with storms are most extensive when they coincide with periods of high lake water. In 1986, the Great Lakes approached record high levels for the modern period; Lakes Superior, St. Clair, and Erie exceeded prior observed highs (Quinn, this volume). Shoreline recession rates grew noticeably in many places; storm damage increased dramatically. A February 1987 storm left Chicago's well-known, armored shoreline in disarray, flooding streets and buildings along the North Shore. As in prior cases of high or low water level, political pressure for a solution became quickly apparent in both the United States and Canada. One result of widespread public concern was the decision of the two countries to request the International Joint Commission (UC) (a binational tribunal created in 1909 to negotiate solutions to problems between the United States and Canada) to initiate a study of methods to alleviate the adverse consequences of fluctuating water levels in the Great Lakes-St. Lawrence River Basin. Such studies had been conducted before, generally yielding proposals for engineering works designed to permit increased regulation of connecting channel flow and, therefore, lake levels. Controls implemented to date include the compensating works at Sault Ste. Marie, some channel modification in the Detroit, St. Clair, and Niagara rivers, and structures in the St. Lawrence River. The planned UC study, however, is not confined to hydrologic regulation or to crisis response. It will examine land use and manage- ment practices along the shorelines and review socioeconomic costs and benefits of alternative land use and shoreline management prac- tices. As directed by the governments, and as elaborated by the UC, the study plan describes, for the first time, a comprehensive examina- tion of the interaction between the lakes and human activities (UC, 1987). Although engineering solutions will be addressed, they are to be considered in the broader social framework of a multielement solution designed with explicit attention to cost-benefit tradeoffs. Against this background, the Water Science and Technology Board (WSTB) selected the subject of Great Lakes levels for its fourth colloquium. The WSTB was intrigued by the complex and interdependent scientific issues underlying the UC study, involving climatology, hydrology, hydraulics, shoreline processes, lake ecology, land use planning, economics, and sociology. In particular, it seemed useful to take the opportunity to engage some 65 persons with ex- pertise and personal involvement in Great Lakes issues in a detailed

4 GREAT LAKES WATER LEVELS discussion of policy options, especially when that discussion could be contemporaneous with the early stages of the IJC study. The WSTB Colloquium on Great Lakes Water Levels: Shoreline Dilemmas was held in Chicago on March 17-18, 1988. The first day was devoted to an inspection tour of the Chicago shoreline and a slide presentation on its history, both led by Lee Botts, deputy commissioner for environmental protection of the city of Chicago, and a keynote address by Michael Ben-Eli, an expert on effective decision making in resource management planning. The colloquium resumed the following day, in the Founder's Room of the Field Museum of Natural History, for the presentation and discussion of the technical papers included in this volume. The first presentations dealt with the nature of water level fluc- tuations (Quinn), the impacts of these fluctuations (Horvath), and the range of strategies for protecting shoreline development (Wood). After this comparatively straightforward progression of ideas, inter- dependencies and complexities were introduced in a discussion of policy conflicts (Pilkey) and legal and institutional issues (Tarlock). As an antidote to the usual tendency to invest public agencies with all the decision-making power, Philipsborn spoke of the response and decision-making role of the individual stakeholders. Two distinct but clearly related topics were addressed in panel discussions. The first dealt with global climate change and its impli- cations for future Great Lakes water levels and management options. The second panel provided an overview of coastal erosion control programs as they are practiced in selected Great Lakes, Atlantic Coast, and Pacific Coast states. Spirited discussion followed each presentation, precipitated by the remarks of an invited provocateur and continued from the floor. Predictably, most controversy arose related to discussions of options for future management policy. Virtually every shade of opinion was represented, from those advocating gradual abandonment of nearly all shoreline to one participant who argued forcefully for "completing the regulation" of the lakes through engineering measures. INVITED PAPERS The people invited to present papers at this colloquium discussed a wide range of topics and brought diverse expertise. To begin, Frank Quinn was charged with the task of summarizing current knowledge of Great Lakes water level fluctuations. After contrasting the period

OVERVIEW 5 of record (beginning in 1860) to available inferences about earlier periods, he continued with a detailed discussion of recent climatic influences and of anthropogenic lake level changes, principally di- versions and limited regulation. He concluded that the period most often used in the past as the basis of design and policy (1900-1969) may not be representative of long-term normal behavior. Rather, the generally higher lake levels of recent years are more consistent with past data and may be a better predictor of the future. On the other hand, global climate warming may eventually lead to lower levels. It seems clear that future policy will have to consider a wider range of variation than has been thought necessary in the past. Curtis Larsen, the assigned provocateur, presented additional data that served to emphasize several of Quinn's points. In partic- ular, Larsen challenged the use of the term "normal" to describe any period of lake levels. Placing the recorded levels of the past 100 years into the context of a 2,000-year geologic record, he argued that historic fluctuations have been much larger, and recent mean levels much lower, than is generally believed. These warnings of increased lake level fluctuation were followed by a discussion of the physical consequences of such fluctuations. This paper, prepared by Horvath, Jannereth, and Shafer and presented by Frank Horvath, reviewed impacts on shoreline morphology, fish and wildlife, water quality, recreation, commercial navigation, and hydro- electric generation. In considering these impacts, the authors noted that both adverse and beneficial effects result from extreme water levels. High water damages property but favors shipping and hydro- electric generation. Low water reverses some impacts but introduces new problems. Horvath also noted a potential for high water-related release of hazardous substances from former waste storage and in- dustrial properties located near the shore. The authors concluded that lake level changes affect virtually every aspect of life in the region, but that society seems to forget quickly the consequences of not planning for extreme levels. Provocateur Sarah Taylor, drawing on references to conflicting interests of various lake users, asked, "For whom will the lakes be managed?" Electric generation and shipping interests may have the most concentrated economic power, but property owners are more numerous and can claim riparian rights. She mentioned additional "silent" parties, including fish and wildlife interests. Lake level man- agement would require setting priorities among these competing uses. William Wood provided an introduction to the principles of

6 GREAT LAKES WATER LEVELS shoreline protection. Reviewing coastal erosion processes, he noted that shoreline recession occurs under both high and low water condi- tions, and that landforms inundated by high water are not likely to reappear. He advocated the notion of a "natural" dynamic boundary for shoreland property, as opposed to the fixed property boundaries assumed by current law and practice. This policy envisions human activities that migrate ahead of receding shorelines, instead of the continual effort to anchor the shoreline. Lengths of unconstructed shore could be "punctuated with limited urban/industrial areas of heavily engineered shores." The application of these strategies could be determined by a system of coastal hazard classifications. Provo- cateur Bruce Mitchell supported many of Wood's points, while ex- pressing reservations about the efficacy of the implied comprehensive planning approach. The discussion of shoreline protection continued with the paper delivered by Orrin Pilkey (prepared by Pilkey, Clayton, and Neal). Pilkey defines the shoreline protection problem as the result of hu- mans placing something permanent in the way of a moving shoreline. He notes that the shoreline processes and protection issues are much alike on the Great Lakes and on the ocean coasts, pointing particu- larly to New Jersey as a lesson for future shoreline management. The characteristics and policy issues associated with various methods of hard stabilization (e.g., seawalls, groins, and breakwaters, including their many variants), soft stabilization (e.g., beach replenishment), and relocation were reviewed. Pilkey discussed policy conflicts inher- ent in several federal programs, and mirrored in many state programs, in which one agency promotes and subsidizes shoreline development while other agencies try to discourage it. Atlantic Coast states have chosen different emphases for their programs, ranging from structural shoreline protection (New Jersey and Florida) to efforts to preserve natural beaches (North Carolina and Maine). Pilkey, like Wood, recommended a mixed strategy combining limited use of hard sta- bilization methods with beach protection and construction setback requirements, as well as relocation incentives. The implied distinction between man-made and natural shore- lines was challenged by Lee Botts, provocateur for the discussion of Pilkey's paper. Botts noted that the beaches and parklands along the Chicago shoreline are entirely man-made. She described a need for better understanding of the role of beaches in shoreline protection, based on increased attention to techniques for beach restoration,

OVERVIEW 1 beach establishment, and beach nourishment. Botts noted that ex- isting federal policies discourage most soft stabilization strategies. The intensive use of the Great Lakes for all types of activ- ity, including the residential development of fully 20 percent of the shorelands, gives rise to a bewildering array of legal and institutional issues, doctrines, and jurisdictions. Dan Tarlock reviewed these prob- lems, noting examples of what he calls "our general confusion about the proper responses to natural hazards." Institutional problems begin at the highest level, with policy and coordination disputes be- tween the United States and Canada. Additional levels of complexity are added by the responses of various agencies of each national gov- ernment, and at the state or province level. Attention was focused on land use controls at the local government level, where incentives to develop shoreland often are created and protected. Any attempt to reverse these policies would, in fact, face substantial potential legal constraints. Tarlock concluded that much of public policy reflects the view that engineering works can eliminate the hazard; adapta- tion to the hazard (e.g., land use controls, relocation) has not yet been considered seriously within these institutions. A note of caution was introduced by provocateur Orie Loucks, who reminded the audience that the most valuable infrastructure is concentrated in densely settled cities, where the adaptive solu- tions described by Tarlock generally are not feasible. Loucks also expressed concern over the "normal range of fluctuation" focus of much of the discussion. Water levels outside of the "normal" range, as contemplated by Quinn and Larsen, may still require water level regulation, irrespective of the effectiveness of other strategies. Clancy Philipsborn directed attention away from public entities, stressing the role of private sector decision makers in the evolution of shoreland policy. He spoke of four types of private stakeholders whose responses contribute to that policy. Those directly affected by water level fluctuations (property owners, for example) are the first-level stakeholders; those indirectly affected (banks, insurance companies) occupy the second level. Third-level stakeholders include engineers and consultants who benefit from otherwise damaging events, and the fourth level consists of volunteers and others who participate in hazard management activities even though they are not directly affected. He stressed the need to anticipate the reactions of the pri- vate sector when formulating public policy. The kind of self-serving, risk-averting behavior that can be expected of most stakeholders can be used to promote public goals, rather than to frustrate them.

8 GREAT LAKES WATER LEVELS Provocateur John Stolzenberg moved from Philipsborn's discus- sion of public-private interactions to the notion of "acceptable risk." He noted that public risk management policy must reflect private per- ception of what is acceptable, even while that perception is formed by information and educational efforts originated by government. Stolzenberg also returned to Taylor's concerns about how priorities are to be set and which interest groups are to be served first. A panel composed of Waltraud Brinkmann, Stanley Changnon, Richard Kosobud, Marie Sanderson, and Joel Smith addressed the controversial and sometimes elusive subject of global climate change. In particular, they were asked to consider the possible consequences of global climate change on Great Lakes water levels. The theories underlying the global warming hypothesis were discussed, along with the models and extrapolations used to predict effects. Much empha- sis was placed on the high levels of uncertainty associated with all such predictions. Most panelists felt that the most likely outcome would be lower water levels in the Great Lakes (coupled with higher ocean levels). Generally, however, the conclusions of the panelists echoed those of Frank Quinn: future Great Lakes managers should be prepared to contend with wider variations in water level than have been seen in the past 125 years. A second panel, composed of Martin Jannereth, Jeanette Leete, Richard McCarthy, and David Owens, was convened to discuss and contrast state coastal erosion management programs. The panelists represented the states of Michigan, Minnesota, California, and North Carolina, respectively. The discussion produced a useful comparison of management strategies, while underlining the essential similarity of coastal erosion problems. The major physical variables appear to be topography and geology, rather than the difference between lake and ocean. Taken as a whole, the panelists' descriptions of program elements made clear and specific what had been presented earlier in the day at a more general and abstract level. From a regulatory perspective, the states use similar approaches and work toward similar goals such as minimizing loss of life and property, preventing encroachment of permanent structures on beaches, and preventing shoreline erosion.

OVERVIEW SUMMARY As the papers in this volume attest, much is known about the causes, characteristics, and consequences of Great Lakes water level fluctuation. Nevertheless, human activities around the lakes have evolved in a way that exposes many people and structures to a hazard of substantial proportions. Every indication is that the magnitude of this hazard will increase in the future. Engineering solutions to minimize this hazard have been proposed but never have been imple- mented. After repeated studies, the effectiveness of these measures remains controversial, and their cost-effectiveness is in doubt. Public policy toward the development and protection of shore lands appears to be at odds with the physical realities of the lakes. In fact, many of the experts involved in this colloquium argued that existing policy seems to assume the possibility, even the probability, of an engineered solution. Yet alternative policies, more reflective of the limits of technology and of sensible cost-benefit tradeoffs, face significant legal, institutional, political, and social constraints. Many of these problems could be resolved, provided the need to do so is widely perceived for a sufficiently long period. In this case, however, the lakes are not cooperating. After reaching record high levels in 1986, water levels began to fall, and the public sense of urgency waned soon thereafter. Many colloquium participants referred to this relationship between water levels and levels of public interests. Perhaps the greatest challenge facing the IJC and the Canadian and U. S. governments, then, is to find a way to formulate and win acceptance for a sensible Great Lakes management policy in the absence of a water level crisis. John J. Boland, Chairman REFERENCES International Joint Commission (IJC). 1987. Directive Concerning the Reference on Fluctuating Water Levels in the Great Lakes-St. Lawrence River Basin. Typescript. April 10. Larsen, C. E. 1985. Geoarchaeological interpretation of Great Lakes coastal environments. In: J. K. Stein and W. R. Farrand, eds., Archaeological Sediments in Context, Peopling of the Americas. Edited Volume Series: Vol. I. Center for the Study of Early Man, Institute for Quaternary Studies, University of Maine at Orono, pp. 91-110. May, S. K., R. Dolan, B. P. Hayden. 1983. Erosion of U.S. shorelines. EOS, Vol. 64, No. 35 (August 30), pp. 521-523.

Issue Papers and Provocateurs' Comments

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Much is known about the causes, characteristics, and consequences of Great Lakes water level fluctuation. Nevertheless, human activities around the lakes have evolved in a way that exposes many people and structures to a hazard of substantial proportions. Every indication is that the magnitude of this hazard will increase in the future. Engineering solutions to minimize this hazard have been proposed but never have been implemented. After repeated studies, the effectiveness of these measures remains controversial, and their cost-effectiveness is in doubt.

Public policy toward the development and protection of shore lands appears to be at odds with the physical realities of the lakes. In fact, many of the experts involved in this colloquium argued that existing policy seems to assume the possibility, even the probability, of an engineered solution. Yet alternative policies, more reflective of the limits of technology and of sensible cost-benefit tradeoffs, face significant legal, institutional, political, and social constraints.

Great Lakes Water Levels: Shoreline Dilemmas explains the recommendations and events of the colloquium. This report explains that many of the Great Lakes' problems could be resolved, provided the need to do so is widely perceived for a sufficiently long period. In this case, however, the lakes are not cooperating. After reaching record high levels in 1986, water levels began to fall, and the public sense of urgency waned soon thereafter. Many colloquium participants referred to this relationship between water levels and levels of public interests. Perhaps the greatest challenge is to find a way to formulate and win acceptance for a sensible Great Lakes management policy in the absence of a water level crisis.

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