Docsity
Docsity

Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity


Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan


Guidelines and tips
Guidelines and tips

Best Practices for Soft Shoreline Engineering: Nov. 1999 Tech Transfer Session Proceedings, Schemes and Mind Maps of Engineering

The proceedings of a November 1999 technology transfer session focused on soft engineering of shorelines. The event, sponsored by various organizations, included presentations on achieving habitat enhancement objectives, comparing soil bioengineering and hard structures, and overcoming regulatory challenges. Participants included representatives from government agencies, universities, and organizations involved in environmental conservation and management.

Typology: Schemes and Mind Maps

2021/2022

Uploaded on 09/27/2022

juno
juno 🇬🇧

4.8

(10)

317 documents

1 / 86

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
University of Windsor University of Windsor
Scholarship at UWindsor Scholarship at UWindsor
State of the Strait Great Lakes Institute for Environmental
Research
2000
Best Management Practices for Soft Engineering of Shorelines Best Management Practices for Soft Engineering of Shorelines
Andrew D. Caulk
Wayne State University
John E. Gannon
United States Geological Survey
John R. Shaw
Environment Canada
John H. Hartig
Greater Detroit American Heritage River Initiative
Follow this and additional works at: https://scholar.uwindsor.ca/softs
Recommended Citation Recommended Citation
Caulk, Andrew D.; Gannon, John E.; Shaw, John R.; and Hartig, John H.. (2000). Best Management
Practices for Soft Engineering of Shorelines.
https://scholar.uwindsor.ca/softs/7
This Publication is brought to you for free and open access by the Great Lakes Institute for Environmental Research
at Scholarship at UWindsor. It has been accepted for inclusion in State of the Strait by an authorized administrator
of Scholarship at UWindsor. For more information, please contact scholarship@uwindsor.ca.
pf3
pf4
pf5
pf8
pf9
pfa
pfd
pfe
pff
pf12
pf13
pf14
pf15
pf16
pf17
pf18
pf19
pf1a
pf1b
pf1c
pf1d
pf1e
pf1f
pf20
pf21
pf22
pf23
pf24
pf25
pf26
pf27
pf28
pf29
pf2a
pf2b
pf2c
pf2d
pf2e
pf2f
pf30
pf31
pf32
pf33
pf34
pf35
pf36
pf37
pf38
pf39
pf3a
pf3b
pf3c
pf3d
pf3e
pf3f
pf40
pf41
pf42
pf43
pf44
pf45
pf46
pf47
pf48
pf49
pf4a
pf4b
pf4c
pf4d
pf4e
pf4f
pf50
pf51
pf52
pf53
pf54
pf55
pf56

Partial preview of the text

Download Best Practices for Soft Shoreline Engineering: Nov. 1999 Tech Transfer Session Proceedings and more Schemes and Mind Maps Engineering in PDF only on Docsity!

University of WindsorUniversity of Windsor

Scholarship at UWindsorScholarship at UWindsor

State of the Strait Great Lakes Institute for Environmental Research

Best Management Practices for Soft Engineering of ShorelinesBest Management Practices for Soft Engineering of Shorelines

Andrew D. Caulk

Wayne State University

John E. Gannon United States Geological Survey

John R. Shaw Environment Canada

John H. Hartig Greater Detroit American Heritage River Initiative

Follow this and additional works at: https://scholar.uwindsor.ca/softs

Recommended CitationRecommended Citation

Caulk, Andrew D.; Gannon, John E.; Shaw, John R.; and Hartig, John H.. (2000). Best Management

Practices for Soft Engineering of Shorelines. https://scholar.uwindsor.ca/softs/

This Publication is brought to you for free and open access by the Great Lakes Institute for Environmental Research at Scholarship at UWindsor. It has been accepted for inclusion in State of the Strait by an authorized administrator of Scholarship at UWindsor. For more information, please contact scholarship@uwindsor.ca.

of Shorelines

Best Management Practices for

Based on a Binational Conference Sponsored by the

Greater Detroit American Heritage River Initiative and Partners

Best Management Practices

for Soft Engineering of Shorelines

Based on a Binational Conference held November 23, 1999 Sponsored by the Greater Detroit American Heritage River Initiative and Partners

© Greater Detroit American Heritage River Initiative, 2000

Edited by: Andrew D. Caulk, Wayne State University John E. Gannon, United States Geological Survey John R. Shaw, Environment Canada John H. Hartig, Greater Detroit American Heritage River Initiative

Citation for this report: Caulk, A.D., J.E. Gannon, J.R. Shaw, and J.H. Hartig. 2000. Best Management Practices for Soft Engineering of Shorelines. Greater Detroit American Heritage River Initiative, Detroit, Michigan. Permission is granted to site portions of this report with proper citation.

Abstract

Historically, many river shorelines were stabilized and hardened with concrete and steel to protect developments from flooding and erosion, or to accommodate commercial navigation or industry. Typically shorelines were developed for a single purpose. Today, there is growing interest in developing shorelines for multiple purposes so that additional benefits can be accrued. Soft engineering is the use of ecological principles and practices to reduce erosion and achieve the stabilization and safety of shorelines, while enhancing habitat, improving aesthetics, and saving money. The purpose of this best management practices manual is to provide insights and technical advice to local governments, developers, planners, consultants, and industries on when, where, why, and how to incorporate soft engineering of shorelines into shoreline redevelopment projects and reap subsequent benefits. More specific technical advice and contact information can be found in the soft engineering case studies presented in this manual.

Our tie to history. Our tie to prosperity. Our tie to each other.

ii Best Management Practices for Soft Engineering of Shorelines

Conference Sponsor:

The Greater Detroit American Heritage River Initiative

Conference Partners:

Canadian Cleanup Committee for the Detroit River RAP Canadian Consulate General Citizen Environment Alliance of Southwestern Ontario City of Detroit City of Windsor Downriver Community Conference Downriver Waterfront Revitalization Task Force DTE Energy Environment Canada, Restoration Programs Division Essex Region Conservation Authority Friends of Detroit River Government of Canada, Great Lakes Sustainability Fund (Formerly Great Lakes 2000 Cleanup Fund) Habitat Advisory Board of the Great Lakes Fisheries Commission Habitat and Headwaters Subcommittee of Rouge RAP Advisory Council Metropolitan Affairs Coalition Michigan Department of Natural Resources Michigan Office of the Great Lakes Michigan Sea Grant Michigan State University Extension Smith Group JJR United States Army Corps of Engineers-Detroit District United States Coast Guard-Marine Safety Office Detroit United States Department of Agriculture-Natural Resources Conservation Service United States Environmental Protection Agency United States Fish and Wildlife Service United States Geological Survey-Great Lakes Science Center University of Michigan University of Windsor-Great Lakes Institute of Environmental Research Wayne County Wayne State University

Cover Photos Top: Goose Bay along the Detroit River (Chapter 6) Bottom: LaSalle Park along Hamilton Harbour, Lake Ontario (Chapter 8)

This report is also available electronically at www.tellusnews.com/ahr/report_cover.html.

iv Best Management Practices for Soft Engineering of Shorelines

Acknowledgements

The November 23, 1999 technology transfer session for soft engineering of shorelines and this report were made possible by financial and in-kind support from a number of organizations and agencies. We gratefully acknowledge such support from:

  • Metropolitan Affairs Coalition;
  • City of Detroit;
  • Habitat Advisory Board of the Great Lakes Fishery Commission;
  • DTE Energy;
  • Smith Group JJR;
  • Michigan Sea Grant;
  • Michigan State University;
  • U.S. Geological Survey-Great Lakes Science Center;
  • Government of Canada, Great Lakes Sustainability Fund (Formerly Great Lakes 2000 Cleanup Fund); and
  • U.S. Environmental Protection Agency.

We would also like to extend our gratitude to:

  • Ms. Marilyn Murphy of U.S. Geological Survey-Great Lakes Science Center and Ms. Linda Hamilton of Metropolitan Affairs Coalition for administrative support in organizing the technology transfer session and handling registrations;
  • Ms. Sue Stetler and Ms. Susan Phillips of Metropolitan Affairs Coalition for help in issuing news releases and to Glenda Marks for graphic design assistance;
  • Drs. Thomas Heidtke and Mumtaz Usmen for assistance in awarding the first American Heritage River Fellowship to a Wayne State University student (Andrew Caulk) to help prepare this report;
  • Ms. Joanne Wotherspoon of Environment Canada for designing the cover of this report; and
  • Mr. Joseph Kubinski of the U.S. Army Corps of Engineers, Detroit District, for providing the technical information included in Figures 7 through 9.

Finally, we gratefully acknowledge the efforts of the authors of the soft engineering case studies presented in this report for sharing their practical knowledge and thoughtful advice. Without their contributions, this report would not have been possible.

Best Management Practices for Soft Engineering of Shorelines 1

Summary and Overview

The Problem of Single Purpose

Shoreline Development

Historically, many river shorelines were stabilized and hardened with concrete and steel to protect develop- ments from flooding and erosion, or to accommodate commercial navigation or industry. Typically shorelines were developed for a single purpose. Today, there is growing support for develop- ment of shorelines for multiple purposes so that additional benefits can be accrued. Up and down our Detroit River, efforts are underway to reshape the riverfront from being concealed in our backyard to becoming the focal point of our attention. General Motors is switching the front door of the Renais- sance Center from Jefferson Avenue to the Detroit River with the building of a five-story Wintergarden (Figure 1).

The Promenade stretching east from the Renaissance Center will further showcase our river for businesses and residents. In Windsor, another three miles of continuous riverfront greenway were opened in 1999 to promote our river and help create an exciting venue for people to work, play, and socialize downtown. In Wyandotte, a new golf course, rowing club, and greenways have directed attention to our river and have resulted in considerable spin-off benefits. People want to increase access to our river, incorporate trails and walkways to it, improve the aesthetic appearance of the shoreline, and reap recreational, ecological, and economic benefits from it. Our Detroit River has been rediscovered as an incredible asset and a key ingredient in achieving quality of life.

Figure 1 General Motors Corporation’s Wintergarden at the Renaissance Center facing the Detroit River.

Rendering courtesy of Hines Development and Skidmore Owings & Merrill, LLP Master Architects.

Our Detroit River has been rediscovered as an incredible asset and a key ingredient in achieving quality of life.

Best Management Practices for Soft Engineering of Shorelines 3

best management practices manual are listed in Table 1. Participants in the November 23 rd soft engineering conference learned that it is important to redevelop and redesign our shorelines for multiple objectives. Shorelines can be stabilized and achieve safety, while increasing public access, enhancing habitat, improving aesthetics, and saving money. Hard engineering of shore- lines, in the form of steel sheet piling, can cost as much as $1,000 per linear foot. We cannot afford to use hard engineering along the entire length of the Detroit River shoreline, nor do we want fully hard engineered shorelines because they have no habitat value and will not support the diversity of fish and wildlife found in our river. Partici- pants also learned that hard and soft engineering are not mutually exclusive, there are places where attributes of hard and soft engineering can be used together. This makes sense in a high- flow river like the Detroit River through which the entire upper Great Lakes pass. It is critically important that the right people get involved up-front in redevelopment projects to be able to incorporate principles of soft engineer-

ing into future waterfront designs. The design process must identify opportuni- ties and establish partnerships early in the process which achieve integrated ecological, economic, and societal objectives.

Integrated Approach

to Design, Implementation,

and Evaluation of

Effectiveness

Figure 2 presents one potential design and implementation framework which encourages incorporating soft engineering practices into shoreline developments. As noted above, it is critically important that the right people get involved up-front in shore- line redevelopment projects to be able to incorporate principles of soft engi- neering into future waterfront designs. However, project leaders must first perform a preliminary assessment which:

  • defines the geographic extent of the project or study area;
  • inventories existing shoreline uses (habitat, public access, etc.); and
  • evaluates existing uses against historical conditions and desired future uses.

A multi-disciplinary team should be formed to reach agreement on goals and multiple objectives for the waterfront and its shoreline.

Table 1 A list of soft engineering case studies presented.

Soft Engineering Case Study Chapter Page

Recommendations from the Incidental Habitat and Access Workshop 1 10 Multiple Objective Soil Bioengineering for Riverbank Restoration 2 16 Comparison of Soil Bioengineering and Hard Structures for Shore Erosion Control: Costs and Effectiveness 3 21 MacDonald Park Wetland and Prairie Restoration Project, St. Clair River 4 25 Constructing Islands for Habitat Rehabilitation in the Upper Mississippi River 5 28 Goose Bay Shoreline Stabilization and Habitat Enhancement 6 35 Fish and Wildlife Habitat and Shoreline Treatments Along the Toronto Waterfront 7 38 Restoring Habitat Ssing Soft Engineering Techniques at LaSalle Park, Hamilton Harbour 8 43 Enhancing Habitat Using Soft Engineering Techniques at the Northeastern Shoreline of Hamilton Harbour 9 46 Bioengineering for Erosion Control and Environmental Improvements, Carson River 10 49 Ford Field Park Streambank Stabilization Project, Rouge River 11 55 Soil Bioengineering for Streambank Protection and Fish Habitat Enhancement, Black Ash Creek 12 62 Achieving Integrated Habitat Enhancement Objectives, Lake Superior 13 66 Battle Creek River, Bringing Back the Banks 14 71

4 Best Management Practices for Soft Engineering of Shorelines

Project leaders must then make a determination of whether or not soft engineering is appropriate. If it is not, resource managers continue with ongoing preservation and conservation efforts. There may also be an opportu- nity to incorporate habitat in the form of rock rubble at the tow of the hard structure. If soft engineering is appropri- ate, an inclusive multidisciplinary process will be required to reap the desired benefits. A multidisciplinary team should be formed to reach agree- ment on goals and multiple objectives for the waterfront and its shoreline. For the design process to be successful, it must identify opportunities and estab-

lish partnerships early in the process which achieve integrated ecological, economic, and societal objectives. Once agreement on goals and multiple objectives has been reached, the multidisciplinary team must set quanti- tative targets to measure progress. The team next evaluates management alternatives and sets priorities. The preferred management practices are then implemented. Following the implemen- tation of these actions, monitoring is performed to evaluate effectiveness. If objectives are met, project success and its benefits are communicated and management agencies continue with preservation and conservation efforts.

Once agreement on goals and multiple objectives has been reached, the multi-disciplinary team must set quantitative targets

to measure progress.

Figure 2 A framework to help incorporate soft engineering practices into shoreline developments.

Continue preservation and conservation efforts

Communicate project success and benefits

N

N Y

Y

Start

Define geographic extent of study area

Inventory existing uses (habitat, public access, etc.)

Evaluate existing uses against historical conditions and desired future uses

Soft engineering appropriate?

Indentify stakeholders and establish partnerships

Reach agreement on goals and mulitple objectives

Set quantitative targets

Evaluate management alternatives and set priorities

Take action

Monitor and evaluate effectiveness

Objectives and targets met?

v v v v v v v v v v v v

v

v

v

v^

v

6 Best Management Practices for Soft Engineering of Shorelines

Concluding Remarks

Urban infrastructure is generally understood to mean the substructure (i.e., roads, sewers) and underlying foundation that provides essential community services. For example, communities need basic services provided by roads and sewers. Re- cently, the concept of “green infrastructure” has been used to communicate importance of the natural resource foundation that provides essential ecological services and related social and economic benefits. Parks, conservation areas, ecological corridors, linked greenways, and open spaces under best management practices all provide essential ecological services and related social and economic benefits. There are numerous examples around North America that demon- strate that putting money into “green infrastructure” and watershed rehabili- tation, enhancement, and protection is not merely a matter of paying for past mistakes, but a sound investment that pays immediate and long-term returns. For example, through the work of the Toronto Waterfront Remedial Action Plan (RAP) and the Toronto Waterfront Regeneration Trust, full costs and benefits of restoration projects in the Lower Don River Valley have been estimated. Capital expenditure on watershed restoration is estimated to be about $964 million (Canadian), along with $1.4 million (Canadian) in annual operating costs. This will lead to capital savings of approximately $ million (Canadian), annual user benefits of approximately $55 million (Canadian), and annual savings of approximately $11 million (Canadian). In addition, the direct economic development benefits include province- wide increases in income of about $3. billion (Canadian) associated with capital investment and $5 billion (Canadian) per year associated with expanded economic activity. Such estimates of full costs and benefits help to provide compelling rationale for watershed management actions. Further, there is growing recognition of the importance of “green infrastruc-

ture” in sustaining our communities, environments, and economies. Healthy communities and economies require healthy environments and “green infrastructure.” “Green infrastructure” is a key element for:

  • achieving community renewal;
  • increasing community awareness, participation, and pride; and
  • sustaining communities and econo- mies. It is the intent of the Greater Detroit American Heritage River Initiative that the advantages of soft engineering practices be recognized and incorpo- rated into many shoreline projects along the Detroit River as a standard for future development. Clearly, greater emphasis must be placed on project evaluation and communication of lessons learned in order to expand the use of soft engineering practices. Participants at the November 23 rd conference identified many places where soft engineering practices might be used, including:
  • Belle Isle;
  • Windsor’s Goose Bay on its east waterfront;
  • Henderson Park and the promenade in Detroit;
  • Hennepin Marsh on Grosse Ile;
  • Wayne County’s Elizabeth Park and Black Lagoon in Trenton;
  • the Gateway Project along the Rouge River within the Automobile National Heritage Area (Figure 3);
  • land owned by National Steel Corporation; and
  • other projects. The time is right to incorporate soft engineering practices into our efforts to redevelop and improve our shorelines. In addition, soft engineering practices should be incorporated in municipal operating manuals and day-to-day operations that affect shoreline use and management. Soft engineering projects also lend themselves to volunteer participation. Let’s work together to showcase the use of multiple-objective soft engineering practices along the Detroit River shoreline and proudly display our region’s new front door.

The time is right to incorporate soft engineering practices into our efforts to redevelop and improve our shorelines. In addition, soft engineering practices should be incorporated in municipal operating manuals and day- to-day operations.

Healthy communities

and economies require healthy environments and “green infrastructure.”

Best Management Practices for Soft Engineering of Shorelines 7

Figure 3 The concrete channel of the lower Rouge River as it exists today (right) and a graphic depiction of what this portion of the lower Rouge River might look like in the future (below). The vision for this area includes greenways, parks, soft engineering of the shoreline, and mixed use redevelopment.

Design credit: Hamilton Anderson Associates.

Photo credit: Wayne County Department of Environment

Best Management Practices for Soft Engineering of Shorelines 9

Leonard, L. 2000. The Watershed Report Card. Peterborough, Ontario, Canada. <http:// www.watershedreportcard.org/>

North Shore of Lake Superior Remedial Action Plans and Scollen and Company, Inc. 1998. Achieving Integrated Habitat Enhancement Objectives – A Technical Manual. Thunder Bay, Ontario, Canada.

Ontario Streams. 1999. Ontario’s Stream Rehabilitation Manual. Belfountain, Ontario, Canada. http://www.ontariostreams.on.ca/toc.htm

Reid, R., K. Rodriguez, and A. Mysz. 1999. State of the Lakes Ecosystem Conference 1998: Biodiversity Investment Areas – Nearshore Terrestrial Ecosystems. <www.on.ec.gc.ca/solec/pdf/ntbia.pdf>

Schacht, B. 1995. Urban stream stabilization efforts which increase instream habitat while controlling bank erosion, p. 149-153. In J.R.M. Kelso and J.H. Hartig [editors]. Methods of modifying habitat to benefit the Great Lakes ecosystem. CISTI (Can. Inst. Sci. Tech. Inf.) Occasional Paper. No. 1, Ottawa, Ontario, Canada.

Schueler, T.R. 1992. Design of stormwater wetland systems: guidelines for creating diverse and effective stormwater wetlands in the mid-Atlantic Region. Metropolitan Washington Council of Governments, Washington, District of Columbia.

Smokorowski, K.E., M.G. Stoneman, V.W. Cairns, C.K. Minns, R.G. Randall, and B. Valere. 1998. Trends in the Nearshore Fish Community of Hamilton Harbour, 1988 to 1997, as Measured Using and Index of Biotic Integrity. Can. Tech. Rept. Fish. Aquat. Sci. No. 2230, Burlington, Ontario, Canada.

Society for Ecological Restoration. 2000. Internet Resources Site. Tucson, Arizona. http://www.ser.org/

Society for Ecological Restoration-Ontario Chapter. 2000. Environmental and Resource Studies Program, Trent University, Peterborough, Ontario, Canada. <www.trentu.ca/ser>

Tulen, L.A., J.H. Hartig, D.M. Dolan, and J.J.H. Ciborowski (eds.). 1998. Rehabilitating and Conserving Detroit River Habitats. Great Lakes Institute for Environmental Research Occasional Publication No. 1. Windsor, Ontario, Canada.

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

U.S. Army Corps of Engineers. 1997. Bioengineering for Streambank Erosion Control. Technical Report EL-97-8, Waterways Experiment Station, Vicksburg, Mississippi. <www.wes.army.mil/el/wetlands/pdfs/el97-8.pdf>

U.S. Army Corps of Engineers. 1999. Engineer Research and Development Center. Vicksburg, Mississippi. <http:// www.erdc.usace.army.mil/>

U.S. Army Corps of Engineers. 2000 (in review). Coastal Engineering Manual, Part VI. Department of the Army, Washington, District of Columbia.

Waldron, G.E. 1997. The Tree Book: Tree Species and Restoration Guide for the Windsor-Essex Region. Project Green, Inc., Windsor, Ontario, Canada.

10 Best Management Practices for Soft Engineering of Shorelines

Chapter 1

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 support- ing 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 associ- ated with the structures include swimming, boating, walking, camping, rowing, diving, picnicing, and sunbath- ing. Breakwaters that have paved walkways allow anglers and strollers better access to the water than unim- proved, rubble mound revetments. At the workshop, attendees were divided into inter-disciplinary 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.

Introduction

Many structures have been built along Great Lakes shorelines, harbors, tributaries, connecting channels, and embayments to serve primary engineer- ing functions of shoreline protection, aid to navigation, and other economi- cally related purposes. Such structures include breakwalls, marinas, jetties, intake and discharge channels, con- fined 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 “inci- dentally” 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 affecting 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 inciden- tal 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 compo- nents, and information on which features can most easily be modified for enhancing incidental habitat and public access.

Recommendations

from the Incidental Habitat and Access Workshop

Philip Moy, University of Wisconsin Sea Grant Institute

12 Best Management Practices for Soft Engineering of Shorelines

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 construc- tion and has more flexibility in the dimension used than the other compo- nents. Bedding stone extends out from the foot of the structure and is exposed for use as habitat. Based on informa- tion 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 con- cluded 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.

Workshop participants concluded that it is highly possible to modify the physical features of Great Lakes naviga- tional structures to improve the habitat and recreational value without adversely affecting the primary navigation or shoreline protection purposes. Encour- agingly, 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.

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

Figure 7 Typical cross-section of a rubble mound breakwater.

DRAWING NOT TO SCALE

DRAWING NOT TO SCALE

Best Management Practices for Soft Engineering of Shorelines 13

Including Incidental

Habitat and Public Access

in the Design Process

Technical information used in the design of U.S. and Canadian Great Lakes coastal structures is based largely on the Shore Protection Manual published by the U.S. 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 interdisci- plinary design team of engineers, biologists, planners, and, when appro- priate, 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 con- straints. The team should continue coordination through the development of plans and specifications to assure that the incidental habitat improve- ments 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. Coordina- tion for a new project begins at the reconnaissance phase, usually through interagency correspondence requesting information on potential impacts to natural resources. Additional coordina-

tion 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 docu- mentation 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 U.S. Army Corps of Engineers; in Canada it is the Depart- ment of Fisheries and Oceans. One should contact the appropriate agency as soon as possible regarding incidental habitat possibilities; the earlier coordi- nation 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 feasibil- ity 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 con- struction. Maintenance Opportunities: New construction on the Great Lakes is increasingly rare, so maintenance activities offer more opportunities to modify an existing structure for inci- dental habitat. Stone must periodically be replaced at rubble mound breakwa-