Chapter 1

Recommendations from the Incidental Habitat and Access Workshop (Philip Moy, University of Wisconsin Sea Grant Institute)

Introduction

Many structures have been built along Great Lakes shorelines, harbors, tributaries, connecting channels, and embayments to serve primary engineering functions of shoreline protection, aid to navigation, and other economically related purposes. Such structures include breakwalls, marinas, jetties, intake and discharge channels, confined disposal facilities (CDFs), navigation cells, and dredge spoil islands. They generally have not been designed to create or enhance habitat or to provide public access, but "incidentally" serve such functions to various degrees.

There was interest within the Great Lakes natural resources management community to explore the ways and means of modifying engineered structures in the Great Lakes to provide an economical and ecological "win-win", and to purposefully improve the habitat and recreational value of the structures without adversely effecting their primary engineered purpose. Consequently, the Great Lakes Fishery Commission's Habitat Advisory Board sponsored the Incidental Habitat and Access Workshop in March of 1994. Participants, including engineers, regulators, biologists, planners, and economists, were challenged in a workshop setting to work together on design features for improving incidental habitat and access associated with physical structures. Ideas developed in the workshop are conducive to soft engineering concepts and principles. A synopsis of the workshop is provided here along with basic information about breakwater, revetment components, and information on which features can most easily be modified for enhancing incidental habitat and public access.

Workshop Synopsis

In preparation for the workshop, a questionnaire was sent to 138 Great Lakes resource managers in 1992. They were asked to characterize incidental habitat use in their region. The responses indicated that incidental habitat at Great Lakes structures is an important feature for humans, fish, and wildlife. These structures attract and provide habitat for sport fish and panfish. Incidental habitat also allows anglers access to the fisheries. These structures provide nesting and roosting sites for waterfowl, as well as supporting many human recreational activities.

The structures are constructed of rock of varying sizes, construction and demolition materials (concrete), and sheet pilings. Many structures use a combination of materials, often in different segments. Some structures have features that facilitate access, while others are unimproved. Handicapped accessibility is increasingly common with the inclusion of concrete walks, guardrails, and fishing piers as design features and additions to existing facilities. Sport fishing, from shore and small boats, is the most common human activity. These structures attract fish, intercept seasonal movements, and provide shore anglers access to deeper water. Other human activities associated with the structures include swimming, boating, walking, camping, rowing, diving, picnicking, and sunbathing. Breakwaters that have paved walkways allow anglers and strollers better access to the water than unimproved, rubble mound revetments.

At the workshop, attendees were divided into interdisciplinary teams. Each team was given a diagram of a physical structure and assigned the task of creating incidental habitat and improving public access. Results of one of the breakout sessions is included here.

This subgroup was given a sketch of a breakwater that provided protection for a harbor and that was used as a navigation aid for an entrance channel (Figure 4). They were also told that a new marina was proposed to be developed adjacent to the existing channel. The results of their deliberations are illustrated in Figure 5. The economic value of the area has been improved by designing the marina as well as improving public access for fishing (boat ramp and fishing access from the breakwall) and hiking (observation platform, footpath, and boardwalk). Concurrently, the ecology of the area has been greatly enhanced by creating a vegetated breakwater between the existing channel and a littoral refuge that creates terrestrial, wetlands, and aquatic habitat. A cross-section through the vegetated breakwater (Figures 6) illustrates how traditional steel sheet piling, widely used in hard engineering approaches, can be used in combination with cobble, geotextile materials, and top soil to create a soft engineered structure that achieves the necessary aid to navigation and shoreline protection, while improving incidental habitat and public access.

Figure 6. Cross-section view at AA on Figure 5, showing combination of hard and soft engineered features. SSP= steel sheet piling.

Workshop participants concluded that it is highly possible to modify the physical features of Great Lakes navigational structures to improve the habitat and recreational value without adversely affecting the primary navigation or shoreline protection purposes. Encouragingly, existing manuals, such as the U.S. Army Corps of Engineers Shore Protection Manual (1984), can be used to create or modify physical structures to enhance incidental habitat, usually with only minor adjustments.

For example, Figure 7 illustrates a cross-section of a rubble mound breakwater; revetments are essentially a half breakwater laying against the shore. The main components are the armor stone, core stone, and underlying bedding or mattress stone. The portion of the bottom-most layer that extends from the foot of the structure is toe stone. The armor stone is the largest and most visible stone of the structure, it is what breaks the waves to protect the harbor. The size or weight of the armor stone is determined by the wave or ice forces expected at the location of the structure. The armor stone weight determines the dimensions of the structure and the other material used in the structure. The core stone supports the armor stone, is relatively unexposed for use as either habitat or access, and has little or no flexibility for habitat modification. The bottom layer of the structure, the bedding stone, covers the lake or river bottom to help support the other components. Bedding stone is the smallest stone used in the construction and has more flexibility in the dimension used than the other components. Bedding stone extends out from the foot of the structure and so is exposed for use as habitat. Based on information from river and lake ecology, a wide range of rock sizes in the bedding stone will provide a mosaic of micro-habitats for fish food organisms, thereby attracting fish for food and shelter (Gannon et al. 1985).

Workshop participants also concluded that the primary hurdle to overcome when enhancing incidental habitat and public access is improving communication between the agency that constructs or maintains the structure and the entity that desires to improve the habitat. Regulators at the workshop strongly emphasized the importance of including incidental habitat and public access features early in the application and design process. Experience has shown that early and effective communication about public access features and incidental habitat is essential to realize such benefits in waterfront designs.

Including Incidental Habitat and Public Access in the Design Process

Technical information used in the design of US and Canadian Great Lakes coastal structures is based largely on the Shore Protection Manual published by the US Army Corps of Engineers (1984). When presented with a project requiring breakwater or revetment construction/repair, the design team will often use a standard approach. On a lake shore, the design condition may be the expected wave or ice climate; in a riverine environment, the design condition may be the water velocity depth associated with a 100-year flood. Since the standard breakwater or revetment design does not include incidental habitat as a component or consideration, ongoing coordination with the design team throughout the design process is required to ensure incorporation of incidental habitat features.

Interdisciplinary Teams:

An interdisciplinary design team of engineers, biologists, planners, and, when appropriate, regulators must be developed. The team should identify potential areas of the structure for incidental habitat improvement, possible means to incorporate them, and engineering constraints. Modification of the incidental habitat proposal may be necessary for the project to remain feasible within the engineering constraints. The team should continue coordination through the development of plans and specifications to assure that the incidental habitat improvements are carried through design to construction.

Regulatory Considerations:

In the United States, engineering projects have five basic phases: reconnaissance, feasibility, design, construction, and operation and maintenance. Coordination for a new project begins at the reconnaissance phase, usually through interagency correspondence requesting information on potential impacts to natural resources. Additional coordination may follow during the feasibility phase, as the National Environmental Policy Act (NEPA) document is prepared. This document is either an Environmental Assessment or an Environmental Impact Statement. Once the NEPA documentation is complete, the project can operate for up to 10 years without preparation of new NEPA documents. New documentation during that period is required if there is a significant change in the operation or dimensions of the structure.

Harbor and shoreline protection structures may be operated by a federal, state, municipal, or private entity. The primary federal agency in the United States is the US Army Corps of Engineers; in Canada it is the Department of Fisheries and Oceans. One should contact the appropriate agency as soon as possible regarding incidental habitat possibilities; the earlier coordination begins prior to a maintenance activity, the greater the likelihood that incidental habitat can be incorporated. In addition, it is more cost effective to modify the structure for incidental habitat during regular maintenance activities than to mobilize equipment specifically for incidental habitat modification.

It is easiest to incorporate incidental habitat at the reconnaissance or feasibility phase. It quickly becomes difficult to insert incidental habitat modifications once the project enters the design phase, and is extremely unlikely that incidental habitat modifications presented during construction will be incorporated. It is advised to maintain close coordination with the project manager or design team to ensure that recommended incidental habitat features are included throughout the design process and are included in the plans and specifications for construction.

Maintenance Opportunities:

New construction on the Great Lakes is increasingly rare, so maintenance activities offer more opportunities to modify an existing structure for incidental habitat. Stone must periodically be replaced at rubble mound breakwaters and revetments. As the timbers begin to decay and the stone weathers, timber crib breakwaters may be encapsulated with either rubble mound or steel sheet pile (Figures 8 and 9). In this process, the old timber crib is surrounded by a new rubble mound or sheet pile structure. Generally the new structure cannot be higher than the original timber crib structure. Rubble mound encapsulation may not be possible if the larger "footprint" infringes upon the navigation channel or other harbor feature.

Sheet pile encapsulation can provide a smaller cross-section at the base. Part of sheet pile encapsulation involves clearing a driving line in the toe or scour stone for the sheet piles at the base of the crib. Instead of removing this old stone from the site, consider placing it nearby to form a small reef (Figure 9), or consider creating a central "disposal" location for the old rock. With material from other maintenance projects this location can become an artificial reef (Gannon 1990). Determine whether there is any flexibility in the size of new scour stone to be used at the project. In addition, sheet pile encapsulation can allow the addition of a concrete cap to provide a smooth walkway.

Figure 8. Typical cross-section of a rubble mound encapsulation.

Figure 9. Typical cross-section of a sheet pile encapsulation.

Aesthetics and Biodiversity:

It is advised to use a variety of textures and vegetation to make accessible areas aesthetically pleasing; use curves rather than straight lines. Nontraditional materials can be incorporated into the structure to diversify the habitat. Vegetation, stone, or wood can be combined to diversify habitat complexity and gradients to help maximize biodiversity. Woody material such as root-wads, brush piles, or timbers, native, endangered, or threatened plants should be used if possible. Water velocity or depth should be varied. Other questions to consider include:

• Is it possible to include wetlands or shallows?
• Are there educational or research opportunities?

One should consider optimal patch use and island biogeography in development of habitat at man-made structures.

Assess Ecosystem Impacts:

All projects produce many impacts on the ecosystem. Asking a few questions before the project starts can help to determine what type of projects should be used. One should assess existing conditions and needs in a watershed, ecosystem, or regional context. What are the indirect and cumulative impacts of the project? Will the project have local or regional impacts? Will there have to be a tradeoff of resource impacts? How will the proposed project impact existing resources? By answering these and other questions, the project can produce maximum benefits.

Public Access Considerations:

What types of access are desired? What kinds of opportunities will be created by improved access? How much access is desirable or acceptable? Should access be restricted in some areas to create refuges for fish or waterfowl? How will people be managed to avoid conflicts between uses, privacy, and operation and maintenance activities? One should develop project management plans that include human and wildlife users. Structures that attract fish also attract anglers. Fixed or floating fishing platforms and boat ramps improve angler access. Consider non-angling activities too; add parking, sanitary facilities, and picnic areas. Providing access to the water and creating attractive habitat can enhance urban recreation opportunities. Access should be barrier-free or barrier-reduced to make the experience available to as many users as possible.

Project Evaluation

Monitoring Plan:

In order to improve future projects, one should develop a monitoring plan to determine whether the incidental habitat modification was beneficial or successful. The plan should monitor fish, wildlife, and human use of the area before and after the project. Recognize that it may take years for algae, macroinvertebrates, and other forage organisms to colonize the structure. Monitoring and research will help determine how to improve incidental habitat and what habitat and access features should be included at new and existing facilities.

Reporting:

Once the success (or failure) of the incidental habitat has been determined, the results should be reported so that others may benefit from the experience. A report should be distributed to all agencies involved and make the results available on the Internet through the Great Lakes Information Network (GLIN; http://www.great-lakes.net). If the incidental habitat modification was not successful, consider how to modify the design and what operational changes to make. Operational changes may be implemented relatively quickly; design changes may have to wait for funding or until routine maintenance is required. An incidental habitat guidance manual describing successful projects and suggested approaches should be developed for planners, developers, and regulators.

References

Gannon, J.E. (ed.). 1990. International position statement and evaluation guidelines for artificial reefs in the Great Lakes. Great Lakes Fishery Commission, Spec. Publ. No. 90-2, page 22, Ann Arbor, Michigan.

Gannon, J.E., R.J. Danehy, J.W. Anderson, G. Merritt, and A.P. Bader. 1985. The ecology of natural shoals in Lake Ontario and their importance to artificial reef development. p. 113-134, In: D'Itri, F. (ed.), Artificial Reefs - Marine and Freshwater Applications, Lewis Publ., Chelsea, Michigan.

US Army Corps of Engineers 1984. Shore Protection Manual, USCOE Waterways Exp. Sta., Vicksburg, Mississippi.

Contact Person

Philip B. Moy
University of Wisconsin Sea Grant Institute
705 Viebahn Street
Manitowoc, WI 54220
pmoy@uwc.edu