Restoring and Protecting Marine Habitat: The Role of Engineering and Technology (1994)

Project success can be defined from various perspectives, but there are no universally accepted measures for gauging project performance or guiding evolving practices (Chapter 2). Regardless, a successful project must be sound with regard to scientific and engineering principles, and these need to be reflected in projects from conceptual stages through construction, performance monitoring, and any corrective action that may be needed.

Marine habitat protection and restoration are not exact science or engineering. A definitive, quantifiable outcome may not be attainable in the near or even long term. Further, project performance needs to be determined on a case-by-case basis to allow for site-specific conditions (Fonseca, 1992; USACE, 1992). Nevertheless, a means is needed to gauge performance. Whenever possible, performance criteria need to be quantitative and measurable (Berger, 1991; Canter, 1993; Westman, 1991). Use of functional performance criteria such as dissolved oxygen profiles in aquatic systems is an option, however the methodology is less well developed than those for measuring ecosystem structure (Cairns and Niederlehner, 1993).

The considerable discussion of defining success stems in part from concern over significant gaps in basic knowledge about ecosystem functions and how to

replicate them. The fact that ill-planned or poorly implemented protection and restoration projects can cause more harm than good argues for a cautious approach to restoration. At the same time, the urgency imposed by continued marine habitat losses demands informed action even if scientific knowledge about ecosystems is incomplete. Recognizing that the state of practice is imperfect, project planning must reflect a general understanding of why projects fail so the basic causal factors can be considered in project goals, objectives, design, and implementation and monitoring.

Failed projects often exhibit one or more of the following characteristics (Landin, 1992c, 1993a):

• incomplete understanding of natural processes;

• poor sites or location;

• poor design;

• incorrect, sloppy, or poorly timed construction or implementation;

• lack of commitment by the permit applicant or contractor;

• inadequate monitoring and corrective action; and

• lack of expertise.

Any of these characteristics can cause failure in one or more of the following technical factors required for successful restoration work (Landin, 1992c):

• correct hydrology or elevation (stable water supply);

• suitable soil/substrate for biotic success;

• protection from wind, wave, current, and wake energies or designed resistance to these forces; and

• correct plant species and propagule selection and installation.

Because the ultimate outcome of each project is performance that satisfies goals and objectives, a practical decision model is needed to guide the formation of goals and objectives, project construction and maintenance, and performance assessment (Landin, in press-a). Such a model would be

• holistic in application;

• multidisciplinary in character;

• highly disciplined (for credibility with the scientific, engineering, and regulatory sectors): and

• flexible (to accommodate the dynamic nature of habitat protection and restoration work over a suitable time scale).

The major components of a decision model for marine habitat protection

FIGURE 6-1 Decision model for achieving success in marine habitat protection and restoration projects.

and restoration (Figure 6-1) reflect an interactive and iterative approach. The model can be adjusted to fit specific circumstances.

Setting achievable project goals (expected results) and objectives (major project elements for attainment of expected results) requires both a comprehensive understanding of the ecosystem of which the project site is a part and a thorough understanding of the social setting. Only then are all interests addressed in the planning and implementation. Project objectives will depend on whether the site will permit or support protection, enhancement, restoration, creation, or a combination of the above. Both near- and long-term objectives are essential because construction or implementation is only an interim step in project development and ultimate performance.

Both ecological and social factors may need to be considered at the outset. They may influence not only the form of the protection or restoration work but also who approves and funds it. For example, a site may be targeted for both natural and human uses, such as recreation. Sometimes the reasons for undertaking

a restoration project are secondary, as is typically the case in navigation projects, which are the funding or material sources for restoration. The primary project objective is then likely to be channel improvement rather than restoration. The dredged sediments cannot be used unless the first objective is met (Landin, 1992c).

An important but often inadequately addressed component of project decision making is involving all the diverse parties so that their interests and concerns are accommodated and they accept ownership in project goals and objectives (Kagan, 1990; NRC, 1992b). Planners and decision makers are often reluctant to expose their plans prematurely, but interagency and public coordination late in a project can severely constrain its implementation and approval (Hamons, 1988; Kagan, 1990). Thus opening the planning process soon after project needs are identified is generally preferable. An open process is a principal way to ensure that all pertinent interests and concerns are identified and accommodated by decision makers, insofar as practical.

Project design follows establishment of goals. Experience shows that design and implementation flexibility is key to project success. The design phase includes establishment of project-specific objectives and interorganizational coordination. Design is site specific, although there are general guidelines for all habitat types (Landin, 1992c). For example, criteria for design and construction of intertidal wetland restoration and sea bird nesting islands are clear and well tested. Most seagrass restoration and other aquatic and marine restoration are still being tested.

Once the need for a marine habitat protection or restoration project has been identified, conditions that existed prior to disturbance or alteration need to be identified, insofar as practical, as do the nature, extent, and impact of present onsite ecological and physical conditions. This information provides a frame of reference for determining what improvements can be made and for developing improvement-specific goals and objectives. For example, a site may be able to support partial restoration to provide a habitat attractive to specific target species, such as clapper rail (an endangered species in California) and the salt marsh harvest mouse at Muzzi Marsh in the San Francisco Bay area (Berger, 1990a). Performance criteria could include establishment of vegetation of sufficient form, quality, and quantity to support target populations. Ultimate success is recolonization (natural or transplanted) of the site at planned levels. Effective application of both scientific knowledge and engineering capabilities is required. For example, when environmental factors are not adequately addressed in design, engineering

components may satisfy design parameters but natural functioning of the site at design levels is not achieved. It will likely be necessary to collect at least some baseline data before specific design can be completed. Additional baseline data may be necessary if vital information such as current or wave data prove inadequate (Landin, 1992c).

Permissibility and success of a project also depend on selected design protocols. Conditions and parameters that define the required physical domain must be established. The degree of complexity of the design depends on the type of habitat desired. The physical characteristics of the physical domain in turn determine management options, including operation and maintenance protocols, through application of engineering principles and technology.

Specific criteria for measuring success and a monitoring and assessment program need to be established and agreed to prior to project implementation so that all interested and affected parties' expectations are clear (Berger, 1991; Canter, 1993; Westman, 1991). Whenever possible, performance criteria need to be quantitative and measurable, although functional assessments may be an alternative in some cases.

Depending on the goals, objectives, and reasons for their establishment, different sets of criteria are needed to measure performance. For example, a project offered in mitigation for development might be held to strict ecological standards for natural functions because marine habitat is disturbed or converted elsewhere. A project providing habitat for a few client species might not require restoration of all natural functions to satisfy the species' habitat requirements in a prescribed time frame. Benefits to other species would be ancillary to principal project objectives. Of course, it is desirable to achieve multiple species benefits whenever possible. Given the gaps in scientific and engineering knowledge of ecological interdependencies, the restoration of all natural functions and diversity would improve the long-term prospects for performing to design objectives.

Design would greatly benefit from incorporation of the latest technical information. This may not always be the best tested information nor information that has been published in the scientific and engineering literature. Most information on local restoration is unpublished or can be found in federal and state agency reports and documents; there are two reasons:

• Most on-the-ground managers of restoration projects have neither the time nor the job incentives to write and publish their techniques.

• Most scientific journals exclude how-to manuscripts as applied rather than basic research or as not scientific enough for their subscribers.

Nevertheless, considerable information is available that could be used to guide restoration work if it were identified and acquired (see Appendix C).

Planning, design, and implementation are improved by a multidisciplinary technical team consisting of engineers, wet soils experts, environmental specialists, hydrologists, and other specialists, depending on the project's environmental and social setting. For example, the assistance of cultural resource and real estate experts may be necessary.

Planning also requires that the team meet regularly to coordinate design components and to coordinate with nonteam partners and interested parties such as cost-sharing partners and resource agency personnel. The potential for success is enhanced when the multidisciplinary team is established for the life of a project, thereby maintaining continuity. An example of the importance placed on interdisciplinary planning is the U.S. Army Corps of Engineers use of specially trained Life Cycle Project Managers in many of its districts to initiate and follow through on all phases of specific projects (or groups of related projects); the Corps also forms restoration and mitigation teams as part of the overall project (Landin, 1992c). The Soil Conservation Service, other agencies, and several large consulting firms use similar strategies for their contracted work.

Project cost is an important factor in determining overall success. With limited financial resources on almost all possible marine habitat restoration projects, low-cost, low-maintenance, stable structures and flexible designs are essential. A lack of funds is not the only reason for low-maintenance goals; the lack of long-term commitments of the agencies that would be responsible for maintenance and management is an important factor. Sites requiring perpetual maintenance may be lost in a matter of years from unintentional neglect, limited budgets, and a limited workforce (Landin, 1992c).

Habitat restoration requiring extensive construction, by definition, cost more than using natural forces, although the latter may take longer. Natural factors can sometimes be used not only to reduce initial construction costs but also to create conditions favorable to natural maintenance of a site, thereby lowering maintenance costs.

Whether the cost effectiveness of some marine habitat projects can be improved

by taking advantage of economies of scale is uncertain. Although it may be possible to lower the cost per acre for some large-scale projects, it is not clear, relative to biological productivity or use by fish and wildlife, whether large-scale restorations offer greater potential as habitat than do small projects of 0.5–2 acres. For example, some small-scale restoration projects that are well-balanced within their ecosystems have been productive. The fact that federal agencies engaged in nonregulatory restoration work seldom attempt a restoration project of less than 10 acres (most encompass hundreds and sometimes thousands of acres) does not necessarily mean that larger is better. Only federal agencies have the mission, resources, and workforce to follow through on extremely large-scale projects (Landin, 1992c).

Evaluation of cost effectiveness is a highly challenging task. Conventional formulas for benefit-cost analysis do not always account for the full value of a habitat (Chapter 5). Further, the functional life of a particular technology is not always known, especially when the technology is new and has not been tested over the long term. Yet when at least some useful information is available with respect to the technology and the habitat, some economies of scale may be possible

Many well-conceived and executed projects fail owing to a lack of appropriate operating protocols, particularly for maintenance of required hydrologic conditions. Although shortcomings generally result from undetected design flaws, numerous marine habitat restoration projects, both regulatory and nonregulatory, that had adequate designs were poorly implemented or constructed (Landin, 1992c).

Good construction techniques are known and practiced. Descriptions of successful engineering and environmental techniques are available from the Army Corps of Engineers, SCS, and EPA primarily, with site-specific information available from the USFWS and NMFS (Allen and Klimas, 1986; WES, 1978, 1986; Kusler and Kentula, 1990; Landin, 1992c; Landin and Smith, 1982; Landin et al., 1990a; SCS, 1992; Soots and Landin, 1978; USACE, 1986, 1989a,b). Good construction techniques include:

• use of correct equipment (such as: light-foot-pressure tracked vehicles for work on a soft substrate; and suitable dredged material placement equipment, for example, correct pipe sizes, dispersive pipe heads, and diffuser pipes, to achieve elevation without prominent mounding);

• use of suitable site preparation and planting gear, which may range from standard farm equipment to bulldozers and from hand planting to use of adapted mechanical planters;

• erection of appropriate temporary or permanent protective structures (such as breakwaters); and

• use of predictive tools (such as GIS, and assessment aids including physical and numeric models).

This generic list is only partial; good practice would expand and adapt it to site-specific restoration projects.

When the project location and design are acceptable, then restoration or enhancement success depends on

• use of the correct construction methodology and equipment, and

• the training, expertise, and attention given to detail and specifications by the project implementors (such as contractors, dredging inspectors, and site managers).

Good plans, designs, and specifications will not compensate for a poorly implemented or constructed project (Landin, 1992c).

Determination of how well a project is performing once implemented requires a scientifically and technically sound, well-planned and well-executed monitoring program. Further, a monitoring regime is only useful if the data that are collected are sufficiently analyzed and applied in a timely manner in determining corrective action regimes for projects that are not performing to design and performance criteria and in the planning and implementation of future projects.

Establishing the period during which performance will be monitored is important (Risser, 1988; Westman, 1991). For seagrass bed restoration or creation, cursory postproject monitoring (simply to see whether the grasses are growing) does not indicate growth patterns or the overall present or possible future health of the ecosystem. Frequent monitoring may be required if the time for vegetation to become established at the site is uncertain (Fonseca, 1992). In general, 0–5 years is considered short-term monitoring for coastal wetlands. Monitoring beyond 5 years is considered long-term (Landin, 1992c).

Marine habitat protection and restoration projects are successful in the absence of monitoring, but the failure to monitor is not sound engineering, scientific, or management practice. Environmental and engineering monitoring is essential for the following reasons (Canter, 1993; Landin, 1992a):

• Provision of baseline data and other essential technical information.

• Documentation of techniques, on-site changes, and chronological events, such as colonization for both the project and subsequent applications.

• Documentation of performance and evaluation of the viability of restoration work.

• Warnings of impacts or impact trends that are approaching critical levels that would necessitate corrective action.

• Assessment of predictive methodologies.

Monitoring needs vary according to habitat type, site-specific conditions, and ultimately, available resources. With regard to environmental and engineering concerns, general monitoring guidelines can be applied. The NRC (1990b) identified a conceptual approach to designing monitoring programs and defined and examined the specific elements of designing and implementing a monitoring program. The approach that follows may be useful to habitat managers in forming a monitoring program for coastal marshes, wildlife islands, mud flats, and other submerged aquatic habitats.

Goals and Performance Criteria Initially, it is important to establish both goals for project performance and specific criteria for determining success (NRC, 1990c). These criteria determine which environmental and engineering sampling methodologies are appropriate (Berger, 1991; Cairns and Niederlehner, 1993; Landin, 1992c; Westman, 1991). It is also important to validate all monitoring methods and equipment used in order to determine variations among sampling stations. Only then can any changes recorded be correctly evaluated.

Preproject Monitoring Determination of goals and performance criteria are aided by preproject monitoring. Preproject baseline data, at the minimum, need seasonal data for no less than 1 full year. They are necessary for addressing year-round, migratory, and temporary habitat use as well as essential functional dynamics of the ecosystem. Some data may be available for some sites, but preproject monitoring will likely be necessary. Data for nearby natural habitats are also useful in determining how well and how long it may take a restoration project to achieve a reasonable level of equality. During project implementation, regular monitoring is needed to document water quality, sedimentation, and immediate and visible effects as to whether or not organisms are inhabiting the area.

The Time Frame for Postproject Monitoring Postproject monitoring begins immediately on completion of construction to establish continuity with preproject monitoring and to document conditions at the site. For the first year, it is generally appropriate to visit the site and collect data (including data from on-site monitoring systems) not less often than monthly. Weekly or biweekly monitoring may be necessary if rapid changes at or in use of the site are indicated. After

the first year, monitoring can generally be relaxed to monthly, perhaps seasonally. After 2 years, seasonal monitoring (at least four times per year) generally suffices. From 3 to 5 years, which is still considered short term, monitoring ranges from seasonal to annual, depending on the stability of the habitat and other site-specific factors. From 5 to 10 years, annual or biennial lower-level (and lower-cost) monitoring usually suffices. Lower-level, lower-cost monitoring can then be conducted at 5-year intervals through the project's twentieth anniversary. Annual or biannual visual inspections or limited sampling at some sites might be prudent to detect any obvious signs of developing problems. For sites with slower-growing wooded vegetation (such as is found in intertidal swamps and maritime forests), periodic site visits are desirable for several decades (Landin, 1992c).

Monitoring Parameters Effective, responsible monitoring and inspection are multidisciplinary. Engineers need data on elevations, consolidation of materials, sedimentation, and topographical changes from preproject through postproject phases. Scientists require baseline data on fish and shellfish, micro- and macroinvertebrates, wildlife, vegetation, soils, water (physical, chemical, and biological parameters), habitat structure, functional dynamics, and other environmental factors during all project phases.

On marshes of all types, seagrasses, mangrove forests, scrub and shrub, and other vegetated sites, all plantings need to be evaluated to determine survival rates, percentage of coverage, reproduction, and other growth indicators (Fonseca, 1992; Landin et al., 1989c). Where plants are allowed to colonize naturally, chronology data documenting colonization of plantings, macro- and microinvertebrate colonization and utilization, and associated functional dynamics are needed. Where plantings are not appropriate owing to the nature and type of habitat, data are needed on the invasion of undesired vegetation and its removal. Experience shows that on restored and created habitat sites, below-ground biomass does not reach natural site levels for more than two decades. Thus root formation and chemical changes in the new soils need to be carefully documented to reflect the natural processes taking place (Landin et al., 1989a,c, 1990a). A useful approach is to compare progress with conditions at a similar habitat site in the area. Although similar habitat would probably be at a mature or climax condition, it can nevertheless serve as a frame of reference for setting objectives.

Monitoring is also feasible for underwater berms, artificial reefs, other deeper water habitats, and seagrass beds. Meriting monitoring are current and wave movements and resulting sediment transport, colonization and habitat utilization by motile and nonmotile organisms, including their abundance and diversity, consolidation, topographic changes, and water quality. For seagrass beds, survival rates, coverage, and other indicators of growth should be included (Landin et al., 1989c; LaSalle et al., 1991).

Establishing permanent observation points (for example, camera stations)

prior to project construction and at least three (or more) permanent transects across an out-of-water site (such as marshes or islands) can greatly facilitate data collection and aid in establishing statistical validity of the data that are collected. Random quadrants (up to 10 per transect) can be used regularly for either destructive or nondestructive sampling, depending on the experimental design. Soil borings, collection of data on micro- and macroinvertebrates in the soils and on above- and below-ground biomass, and all vegetation parameters can be taken from the quadrants. The same transects can be used as belts through the establishment of a 10 meter line on either side to record all wildlife. Enclosure cages may also be installed if nutria or waterfowl grazing is expected to cause problems with data collection.

The establishment of sampling points for in-water sites and mud flats can include fish nets, Breder traps, and other fish-sampling apparatuses. However, they may have to be set up after a project is built owing to changes that take place on-site during construction. Apparatuses used for preproject fish and other in-water data may have to be removed if permanently installed because of changes in site condition, such as elevation. Where shorebird feeding pressures are expected, installing enclosure cages on mud flats and sites adjacent to the shore may be feasible (Landin, 1992a; Landin et al., 1989c).

Because fully developing and attaining marine habitat protection and restoration project goals typically requires years, a long-term management strategy is needed. Yet, effective maintenance and management are often overlooked. For example, a permit applicant for a mitigation project is usually required to provide baseline data (monitoring and inspection) for a maximum of only 3, sometimes 5 years. This short time period does not provide for determining long-term performance or entail the need for midcourse corrections. Similarly, federal agencies do not always allow for long-term maintenance and management.

Establishment of a long-term management strategy is desirable as part of the project approval process. An effective management strategy incorporates a commitment and the resources to execute it, monitoring regimes, and responsibility for corrective action that may become necessary during a project's design life.

Success can be defined from ecological or practical perspectives. Defining success as achieving project goals and objectives is sufficiently flexible to accommodate both ecological and social (including economic) objectives and to provide a means for judging project performance in the absence of complete science and engineering knowledge. Success as determined by predefined measures can be achieved through careful coordination and planning, effective design,

implementation, construction protocols and techniques, extensive monitoring and inspection, and maintenance and management. Technology transfer, adequate communication, and networking among restoration practitioners are vital, as is the need for good science and engineering. A multidisciplinary project design and implementation team can generally overcome or accommodate gaps in scientific or technical knowledge affecting design and performance.