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ENVIRONMENT IN COASTAL ENGINEERING: DEFINITIONS AND EXAMPLES** Cyril Galvin, M. ASCE* ABSTRACT In current usage, environmental aspects of coastal engineering design include aspects of ecology and aesthe- tics, as well as environment. In practice, the aspect of environment is a limited one, considering man's surround- ings, with the works of man left out. The increased consid- eration of environmental aspects over the past 15 years has brought real benefits to the coastal engineering profession, as well as obvious problems. One problem is a mythology of coastal processes that has become widely accepted. Priori- ties in coastal engineering design remain a structure that will last a useful lifetime and perform its intended func- tion without creating new problems. After satisfying these fundamental requirements, the structure should minimize ecological change, and fit pleasingly in its setting. INTRODUCTION Design and THE Environment. A coastal structure must remain standing when hit by the most severe waves, currents, and winds that can reasonably be expected during its intended lifetime. Waves, currents, and winds are basic elements of the physical environment. In this structural sense, good coastal engineering is always sensitive to the environment. But the designer who creates a structure that doesn't fall down has not necessarily solved a coastal problem. The structure must also perform a function, without creating significant new problems. it must reduce beach erosion, prevent flooding, maintain a channel, provide a quiet anchorage, convey liquids across the shore, or serve other functions. There are groins standing out at sea after the beach has eroded away; jetties exist that enclose a deposit of sand rather than a navigable waterway; some seawalls are regularly overtopped by moderate seas; water intakes are silted in. •Principal Coastal Engineer, Cyril Galvin, Coastal Engineer, Box 623, Springfield, Virginia 22150, USA. ** This paper Is an overview of the papers discussed in the poster session on Environmental Aspects in Coastal Engineering Design. The papers dis- cussed are presented in Chapters 136-137. 2264 COASTAL ENGINEERING ENVIRONMENT 2265 These functional failures are no less costly than structural failures. To design a structure to function as intended requires a thorough knowledge of the coastal pro- cesses affecting the site. These coastal processes are basic elements of the environment. So in the functional sense also, good coastal engineering is always sensitive to the environment. But physical factors of the environment (waves, cur- rents, sediment transport, etc.) are not the principal fac- tors of THE environment, as that word is now used in dis- cussing environmental aspects of coastal engineering. "Pro- tect the Environment" does not mean protect the design wave height. Rather, "Protect the Environment" means protect a complex of factors including fish and wildlife, wetlands, scenic views, water quality, odors and sounds, low popula- tion density, and even the subjective imaginings of people who will never see the sight. Intent of this Paper. This paper is about the relation between coastal engineering and the environment in the above contemporary sense. The occasion of the paper was a poster session "Environmental Aspects in Coastal Engineering Design" held on 15 November 1982 in Cape Town as a part of the 18th International Conference on Coastal Engineering. A poster session provides for the individual authors to pub- lish abstracts of their papers and to display key illustra- tions from their papers at the meeting hall during the conference. The chairman of the session discusses the authors' papers and the general subject, and puts his ideas in a paper. This is the chairman's paper for the poster session on "Environmental Aspects in Coastal Engineering Design." Given the occasion of this paper, it should serve two functions: review the work of the individual authors taking part in the session, and comment on the subject matter in general. There are 4 papers eligible for review, that is, 4 papers whose abstracts were published in the conference abstract volume and whose authors displayed their results at the conference. These are the works of Perry (1982), Clark (1982), Hoffman, Mussalli, and Taft (1982), and Geldenhuys (1982) . The next section of this paper defines and distin- guishes the meanings of environment as they apply to this paper. Following these definitions, four sections review each of the poster papers. The final section presents opin- ions of the writer on environmental considerations in coas- tal engineering design. 2266 COASTAL ENGINEERING—1982 DEFINITIONS To a large extent, words mean whatever their users think they mean. This has been especially the case in dis- cussing environmental questions. Nevertheless, it is useful to review the accepted meanings of key words that are a part of the discussion. There are three words particularly rele- vant here: Environment, Ecology, and Aesthetics. The authoritative sources of meanings are dictionaries, and the most authoritative dictionary for the English lan- guage is the Oxford English Dictionary (OED), issued in corrected form in 1933 with later supplements. A more con- temporary and concise dictionary is the Oxford American Dictionary (1980). These two dictionaries (the OED and the OAD) are the sources of the following definitions. Environment. Environment, according to the 1933 OED, comes from a French word meaning to encircle. Two defini- tions are given, the first and most general being "the object or regions surrounding anything." The second defini- tion is "the conditions under which any person or thing lives or is developed; the sum-total of influences which modify and determine the development of life or character." The 1980 OAD defines environment as "surroundings, especially those affecting people's lives." The coastal engineer developing a design wave height for a structure considers the environment in the first sense of these dictionary definitions. Once it is built, the structure itself becomes part of the coastal environment in this sense. But the environment, as used in the phrase "Protect the Environment", implies a slightly different definition; environment in this usage corresponds roughly to animals, plants, and the natural landscape, with the works of man removed. As used in this environmental sense, the meaning approaches that of 'ecology'. Ecology. The word, 'Ecology1, as such, does not appear in the 1933 OED. At that time the accepted spelling was 'oecology', which is defined as "The science of the economy of animals and plants; that branch of biology which deals with the relations of living organisms to their surround- ings, their habits and modes of life, etc." (The 1972 Supplement to the OED now accepts 'ecology' as the more usual spelling.) COASTAL ENGINEERING ENVIRONMENT 2267 The 1980 OAD shows the evolution in meaning of ecology that has accompanied recent usage. The first OAD definition of ecology is a concise restatement of the 1933 OED defini- tion: "The scientific study of living things in relation to each other and to their environment". The second definition is simply "this relationship", i.e., the study of relation- ship among organisms which was the original meaning of ecology is now coming to be replaced by the relationship itself. The OAD editors also add a postscript to their definition: "Note that ecology does not mean environment." Relationships among native species and their environ- ment, i.e., the ecology, may be affected by coastal engi- neering works, and the works themselves may be affected by the ecology. As an example, improving an inlet to make it more navigable may also increase the tidal prism, and thus change the salinity of the bay waters. Changed salinity could increase or decrease the productivity of oyster beds in the bay, an effect of a structure on the ecology. It could also change the abundance of marine borers infesting timber piles and bulkheads in the bay, an effect of the ecology on those timber structures. Depending on the cir- cumstances, the net effect of the changes may be beneficial or harmful, although the doubt is usually in favor of main- taining the status quo, since the individuals whose liveli- hood is most threatened by such changes often hold a poten- tial veto over the approval of the project. The practical effect of these considerations is the development of a new functional design requirement for a coastal structure: the structure should not cause any sig- nificant change in the existing ecology, except for changes (such as improved water quality) that are not strongly opposed by any element of the affected population. Aesthetics. 'Environment' and 'ecology' are words that have become commonplace. Their meaning may be vague, and one is often confused with the other, but these two words undoubtedly connote good things that people are in favor of. It has been the writer's experience, however, that regula- tory decisions made in the name of the environment or ecology are often based, not on ecological principles, but on the personal philosophy of the regulator about what is right, i.e., what contributes to beauty in the situation. Often, in fact, the regulator has relatively little ecolo- gical data to base a decision on. In these decisions, personal aesthetics and not the environment or ecology, determines the outcome. Aesthetics is defined (1933 OED) as "The philosophy or theory of taste, 2268 COASTAL ENGINEERING—1982 or of the perception of the beautiful in nature and art." The 1980 OAD defines aesthetics as "a branch of philosopohy dealing with the principles of beauty in art." Few people, of course, formally sit down and write out their personal theory of what is pleasing and beautiful in nature, and then make decisions consciously following this formulation. It is more intuitive than that. Some things fit and others do not. Given the choice, wilderness is more appealing than development; clear water is preferred to turbid water; dunes are more natural than seawalls; and so on.

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