Eco-Logical: An Ecosystem Approach to
Developing Infrastructure Projects

IV. Incorporating an Ecosystem Approach with Mitigation Decisions

The integrated planning process and regional ecosystem framework (REF) can help agencies achieve tangible gains for ecosystems. By identifying the specific areas where impacts to species, habitat types, and other important ecological functions could be best offset, agencies can use their integrated plans and REF to more effectively choose from a range of mitigation options, should mitigation be necessary. When making mitigation decisions, interagency teams are encouraged to select the mitigation approach that not only complies with regulatory requirements, but that also yields the greatest benefit for the ecosystem while remaining economically fitting given the estimate of impacts from planned improvements.

A regional ecosystem approach offers a potentially enhanced system for crediting mitigation that can help ensure that regional conservation goals and objectives are accomplished. This system builds on existing banking options that were developed for multiple-project mitigation, specifically, wetlands banking and conservation banking. Using an approach that emphasizes regional ecosystem needs and priorities, and drawing on the lessons learned from previous experience, agencies and the public can explore the opportunities and incentives to maximize prospects for connectivity conservation gains while producing necessary infrastructure. To begin, however, the existing mitigation options should be understood. The following section describes these options, concluding with a discussion of the concept of ecosystem-based mitigation agreements.

Mitigation Options

Mitigation options include:

• Project-specific mitigation
• Multiple-project mitigation
  - Mitigation banking
  - In-lieu fee mitigation
  - Conservation banking
• Ecosystem-based mitigation agreements

Whichever of these options is used, the goal is to restore, create, enhance, and/or preserve natural resources for the purpose of compensating for unavoidable resource impacts. Mitigation helps ensure that ecosystems, habitats, and species populations remain sustainable and productive over time. The Council on Environmental Quality (CEQ) regulations (40 CFR 1508.20) define mitigation as:

1. Avoiding an impact altogether by not taking a certain action or parts of an action;
2. Minimizing impacts by limiting the degree or magnitude of the action and its implementation;
3. Rectifying the impact by repairing, rehabilitating, or restoring the affected environment;
4. Reducing the impact over time by preservation and maintenance operations during the life of the action;
5. Compensating for the impact by replacing or providing substitute resources or environments.

Existing regulation and guidance on mitigation for wetlands, streams, and other aquatic resources (hereafter described as aquatic resources) expresses CEQ's definition in a three-step approach. Applicant(s) proposing to impact aquatic resources must abide by a specific sequence that directs the applicant to:

• Make efforts to avoid impacts to aquatic resources, then
• Minimize remaining impacts to aquatic resources, and finally,
• Provide compensatory mitigation for unavoidable impacts to aquatic resources.

These requirements for sequencing impacts to aquatic resources are required prior to the selection of any type of compensatory mitigation described below.

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Project-Specific Mitigation

Traditionally, compensatory mitigation has been carried out on a project-by-project basis; specific measures are implemented to mitigate a project's impacts at a site that is usually on or adjacent to the impact site. Project-specific mitigation is usually selected based on the impact-site location, usually does not address landscape or watershed perspectives, and is generally small in scale. During the environmental review and permitting phase of project development, regulatory agencies will assess the expected impacts of the project and set a proposed threshold for mitigation. The applicant or project sponsor is then responsible for developing the mitigation proposal that is presented to the agencies to confirm how project impacts can be mitigated. The mitigation can be on-site or off-site and in-kind (of similar resource or ecological function as the impact) or out-of-kind, however there has traditionally been a flexible preference for on-site and in-kind compensation.

In some cases, on-site, in-kind mitigation may not yield the greatest benefit to an ecosystem. In 2001, the National Academy of Sciences National Research Council (NAS/NRC) recognized this shortcoming of traditional approaches to mitigation in their report titled "Compensating for Wetland Losses Under the Clean Water Act." This report states "The [NAS/NRC] committee endorses the watershed approach and finds the automatic preference for in-kind and on-site compensatory mitigation…to be inconsistent with that approach." The NAS/NRC report noted that often there are circumstances in which on-site or in-kind mitigation is not practicable nor is it environmentally preferable under a watershed approach.

The results of project-specific mitigation under the Section 404 regulatory program have been evaluated several times, with the finding that often the mitigation is not fully implemented, is improperly designed and constructed, and in some cases, is never done at all. However, project-specific mitigation projects are an accepted means of providing compensatory mitigation with established administrative procedures. When properly designed and implemented, and appropriately monitored, this approach offers a predictable and tested way of achieving compensatory mitigation as well as the opportunity to protect unique, on-site natural features. In addition, there is a suite of ecological functions that may be best mitigated on or near the project site. For these reasons, project-specific mitigation remains a preferable option in some cases.

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Multiple-Project Mitigation

Multiple-project mitigation involves using a single, and typically large, off-site mitigation project to serve as compensation for impacts resulting from multiple projects. Both the 1995 Federal Guidance for the Establishment, Use and Operation of Mitigation Banks (1995 Federal Banking Guidance) (60 Fed. Reg. 58695, November 28, 1995) and the Federal Guidance on the Use of In-Lieu-Fee Arrangements for Compensatory Mitigation under Section 404 of the CWA and Section 10 of the Rivers and Harbors Act (2000 Federal In-Lieu-Fee Guidance) (65 CFR 66913, November 7, 2000) recognize that for small projects, off-site mitigation, such as that provided by a bank or in-lieu-fee, is often preferable. With off-site mitigation, a number of small projects that would usually result in scattered mitigation can be consolidated into a larger mitigation project, increasing the chances of ecological success.

Multiple-project mitigation can be divided into the following categories: mitigation banking, in-lieu-fee arrangements, conservation banking and ecosystem-based mitigation. Each is described below.

Mitigation Banking

To help mitigate historic wetland loss, a statewide, ecoregion-based mitigation banking system was initiated by the Arkansas Highway and Transportation Department in 1996, when a mitigation bank came online in the Mississippi Alluvial Plain ecoregion of eastern Arkansas. Since 1996, AHTD has established one bank in each of the State's five ecoregions, creating eleven mitigation areas—a total of nearly 3,020 acres. The banks, which are used by egrets and other bird species, were created through collaboration among AHTD, FHWA, USACE, USFWS, the Natural Resources Conservation Service, EPA, the Arkansas Game and Fish Commission, the Arkansas Natural Heritage Commission, and the Arkansas Soil and Water Commission.

Mitigation banks are specifically targeted toward aquatic resource mitigation needs in the CWA Section 404 Regulatory Program and wetland conservation provisions of the Food Security Act. They involve the restoration, creation, enhancement, and—in exceptional circumstances—preservation of aquatic resources expressly for the purpose of compensating for unavoidable aquatic resource losses. This method is used when compensation at the development site cannot be wholly achieved or would not be as environmentally beneficial. Generally, mitigation banking involves the establishment of wetland and aquatic habitat by the bank sponsor in advance of development actions. Infrastructure developers can purchase "credits" from the bank sponsor to provide compensatory mitigation for unavoidable impacts at the proposed project site. Mitigation banks are established through a permitting process that includes development of banking agreements signed by the USACE, responsible resource agencies, and the bank sponsor.

The 1995 Federal Banking Guidance further clarifies the policy on mitigation banks for the purpose of providing compensatory mitigation for authorized adverse impacts to aquatic resources. According to the Federal Guidance, "In general, use of a mitigation bank to compensate for minor aquatic resource impacts (e.g., numerous small impacts associated with linear projects; impacts authorized under nationwide permits) is preferable to on-site mitigation." The overall goal of a mitigation bank is to provide economically efficient and flexible mitigation opportunities, while fully compensating for wetland and other aquatic resource losses in a manner that contributes to the long-term ecological functioning of the watershed within which the bank is to be located. The goal will include the need to replace essential aquatic functions that are anticipated to be lost through authorized activities within the bank's service area. Consistent with this guidance, permittees may use mitigation credits from a bank, approved through the established Mitigation Banking Review Team, as compensation, in whole or in part, for unavoidable losses to the aquatic environment. Mitigation banks will generally reduce uncertainty over the ecological success of the mitigation.

In-Lieu-Fee Mitigations

Another form of multiple-project mitigation is in-lieu-fee mitigation. An in-lieu-fee arrangement provides required compensatory mitigation off site for impacts to wetlands. In-lieu-fee mitigation is cost-based and occurs in circumstances where either an agency seeking a permit, or another party, provides payment for mitigation to a sponsor for future mitigation projects instead of completing project-specific mitigation or purchasing credits from an approved mitigation bank.

Unlike mitigation banks, in-lieu fees do not typically provide compensatory mitigation in advance of project impacts; rather, they are either paid concurrently with a project or after the impacts have occurred. In-lieu-fee programs usually have not acquired or constructed an existing mitigation site when the fee is paid.

A 2001 Government Accountability Office Report, "Wetlands Protection: Assessments Needed to Determine Effectiveness of In-Lieu-Fee Mitigation" states that USACE has established 63 in-lieu-fee arrangements since the first one was used in the late 1980s. When the report was published, arrangements had been made in 17 of 38 USACE regulatory districts, and at least 8 other districts had planned to establish such arrangements in the future. The report also raised a number of concerns regarding the administration and ecological effectiveness of in-lieu-fee arrangements and provided recommendations for addressing these concerns. Anticipating these concerns, the 2000 Federal In-Lieu-Fee Guidance clarified the need for in-lieu-fee arrangements to be held to standards similar to those used in mitigation banking. This has increased the challenges of establishing viable in-lieu-fee arrangements.

Conservation Banking

Conservation banks are parcels of land containing natural resource values that are conserved and managed in perpetuity for specified listed species and used to offset impacts occurring elsewhere to the same resource values on nonbank lands. These banks, which must be approved by the USFWS and the State agency responsible for protecting State-listed species, are established for the long-term protection of a specific species that is impacted on a project's site.

Like mitigation banks, conservation banks must remain under active management in perpetuity and can be either privately or publicly owned. In each case, the bank operator is allowed to sell credits to infrastructure agencies needing to satisfy legal requirements for the compensation of their projects' environmental impacts. When an agency buys conservation bank credits, it is guaranteeing the restoration and/or permanent protection of that bank for its stated purpose.

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Characteristics of Mitigation and Conservation Banks

Characteristics of the most successful mitigation and conservation banking scenarios are described below.

• Net Benefits of Banks - Mitigation is initiated earlier, frequently ahead of project impacts, as compared to on-site, project-specific mitigation, which often occurs after the project is underway or complete, resulting in temporal loss of functions and benefits. Banking provides substantially increased assurance of success in the long run; uncertainty of mitigation results is reduced. Habitats are conserved sooner, in better locations, and/or with more consideration for landscape integrity.
• Credit Valuation in Existing Mitigation Banks - The determination of credits at mitigation banks should reflect the estimated increase in ecological functions resulting from successful implementation of the bank site's restoration plan. The approach can be basic, relying on the measurement of acres impacted and replaced, or on some assessment of function or value. In order to facilitate transactions at a bank, the same assessment technique used to determine the number of credits at the bank is often used to quantify the aquatic resource losses at impact sites. Different agencies, stakeholders, and partners often view the value of a credit differently. Any particular group may use more than one way of valuing the credit that environmental goods and services have:
  • Qualitative Ecological Value, which may be based on perceived effect on the species of interest, an ecosystem value such as wetland function, or recreation, water quality, etc.;
  • Quantitative Ecological Value, for example, the number of units protected or enhanced, or changes in functional characteristics; and
  • Economic Value - market value, price, and replacement value are ways of measuring economic value.
• Ratios - Under Section 404 of the CWA, most compensatory mitigation is required at some ratio greater than 1:1, relative to impacts. The "no net loss of aquatic resources and wetlands" is a principal goal of USACE and ratios are applied to ensure that this goal is met. In some cases, compensatory mitigation requirements under Section 404 of the CWA include a larger compensation ratio, e.g., a 2:1 ratio that requires 2 acres of mitigation for every 1 acre of impact. Ratios are sometimes used to account for the difference between a fully functional impact site versus a partially functional mitigation site, or to offset the time lag before a mitigation site becomes functional. Compensation ratios should not be used to account for uncertainty, offset a decreased predictability of success, or serve to reflect the lack of clear liability if something goes wrong. Instead, performance bonds, enforceable permit conditions, or other legal mechanisms should be used to assure the success of mitigation sites.
• Timing - The Federal Banking Guidance states that mitigation credits should be released at a rate commensurate with the level of function at that bank, that is, credits should only be sold after they have accrued. However, the Banking Guidance also recognizes that mitigation bankers need to generate income to undertake restoration or enhancement activities. Thus banks are allowed to sell a limited amount of credits in advance, provided that the bank site has been secured and the bank plan has been approved; in addition, the initial work on the site must begin within one year of selling the credits.
• Credit Recognition - Banks usually operate under a multi-agency agreement that includes standards and procedures for determining how to certify that mitigation credits are available.

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Ecosystem-Based Mitigation Agreements

Existing options for compensatory mitigation are helpful and practical approaches. In some cases, they have significantly contributed to ecosystem health. However, they might not always offer the most effective methods for deriving the greatest environmental benefit and achieving goals of connectivity, conservation, predictability, and transparency. Ecosystem-based mitigation can merge attributes of existing mitigation options to enable agencies to move closer to these goals. Characteristics of ecosystem-based mitigation include the following:

Concerns with potential habitat fragmentation by proposed highway improvements resulted in studies by the Wyoming DOT (WYDOT) to collect primary data about wildlife crossing zones and wildlife-vehicle collisions. The information collected will be used to identify mitigation opportunities and accommodate wildlife crossings into design plans, based on landscape-level habitat needs. To oversee the study, a steering committee was formed with representatives from USDA FS, the Wyoming Game and Fish Department, the Jackson Hole Alliance, FHWA, and WYDOT. (Photo courtesy of WYDOT)

• Builds on Existing Banking Systems - Ecosystem-based mitigation builds upon the experience of mitigation banks and conservation banks. Wetland mitigation banks were initially developed to improve mitigation practices. Conservation banks expanded this idea to allow limited impacts to the habitat of threatened and endangered species. Ecosystem-based mitigation could combine these concepts - instead of looking at wetland mitigation and species mitigation as separate activities, ecosystem-based mitigation agreements could look at these and other resource functions of the ecosystem holistically and look for synergistic opportunities - adding a cumulative value to these systems. By encompassing wetland and upland habitat into a complete mosaic, strategically located within a landscape and/or watershed, ecosystem-based mitigation will enable the protection of ecological functions, values, and processes that are believed to be most important for the regional ecosystem.
• Is an Outgrowth of Integrated Planning - In an ecosystem-based mitigation system, the process of integrated planning will have produced a regional ecosystem framework, or REF, identifying a hierarchy of important resources in a region and their locations. Logically, decisions to provide mitigation in the most ecologically important locations should lead to an environmentally preferable result - if the mitigation occurs and is successful. Accordingly, the service areas for ecosystem banks may differ from those of mitigation banks and conservation banks. Depending upon the nature of the ecosystem mitigation proposal, the range of impacts for which it provides mitigation may be larger or smaller than the service areas of mitigation and conservation banks in the same region, and the impacts may be defined with reference to ecological areas and resources identified during integrated planning. Ultimately, CWA and ESA regulators must approve the service area of an ecosystem bank if it used to offset impacts authorized under these statutes.

  In addition, potentially impacted resources will have been prioritized during integrated planning. A multi-agency steering group can then guide the development of a regional mitigation plan, based on the REF, that establishes a system of accountability and how it will be measured.

• Is Consistent with Federal Legislation - Ecosystem-based mitigation is an approach to long-term conservation similar to those already encouraged in laws and regulations. In existing Federal guidance on mitigation, mitigation banks are considered an appropriate way to satisfy compensatory mitigation requirements off site when 1) on-site compensation is not practicable, or 2) use of the mitigation bank is environmentally preferable to on-site compensation. Similarly, Federal guidance on in-lieu-fee mitigation (see https://www.epa.gov/cwa-404/policy-and-guidance-documents-under-cwa-section-404) states that in-lieu-fee mitigation is appropriate in circumstances when on-site compensation is not available, practicable, or is less environmentally desirable. Concerning in-kind versus out-of-kind mitigation, a 1990 MOA between EPA and the Department of the Army states that acceptable out-of-kind compensatory mitigation may occur in the use of a mitigation bank where it is environmentally preferable. [1990 MOA - US Environmental Protection Agency and US Department of the Army. Memorandum of Agreement Between the Environmental Protection Agency and the Department of the Army Concerning the Determination of Mitigation Under the Clean Water Act Section 404(b)(1) Guidelines. 1990.]

  The last two Federal transportation acts have included provisions that explicitly encourage the use of mitigation banks to compensate for impacts to aquatic resources associated with Federal-aid highway projects. The 2003 Federal Guidance on the Use of the TEA-21 Preference for Mitigation Banking to fulfill Mitigation Requirements under Section 404 of the Clean Water Act clarifies the application of this preference consistent with CWA requirements.

  Ecosystem-based mitigation agreements can also be used to promote interagency cooperation as prescribed under Section 7 of the ESA, as amended. The development of a REF and its requisite plans can offer a way to quantify restoration efforts that promote minimization of impacts and avoidance of jeopardy. Quantification of resource values could facilitate equitable or improved comparison between proposed ecological restoration activities and the impacts to those values by a proposed project.

• Takes Advantage of Vanishing Opportunities - Many involved in the development of infrastructure projects have been faced with a "vanishing opportunity" - where there was a need to act in a timely way on a situation that could yield outstanding ecological benefits. Delay could lead to a loss of the opportunity, perhaps never to see another one like it. These circumstances are becoming increasingly common as pristine or critical ecological resources are developed, many permanently. This is the crux of ecosystem-based mitigation—to take advantage of these vanishing opportunities before they are lost. It is difficult, if not impossible, to "turn back the clock" and restore ecological functions and benefits of natural landscapes, communities, and habitats that have been severely altered or have experienced land-use change. Taking an ecosystem approach to mitigation can help maintain large-scale functionality, with the realization that total preservation is not an option and that tradeoffs are necessary.

  Ecosystem-based mitigation takes a broad, "landscape-integrity," view of compensating for impacts of infrastructure projects, while still meeting the regulatory mandates of the applicable laws and regulations. The watershed or regional scope of such mitigation would encompass large ecosystems with critical functions in need of protection or augmentation. Examples of such a scale are the Northern Continental Divide Ecosystem in Montana as defined by the International Grizzly Bear Committee, the Salmon River Ecosystem, and the Greater Yellowstone/Grand Teton Ecosystem in Montana and Wyoming. These large ecosystems, although covering vast expanses of land, can be tightly tied into functional wholes by the need for large-scale landscapes to support the diverse requirements of their respective plants and animals.

Accountability in Ecosystem-Based Mitigation

One aspect of accountability in mitigation and conservation banking is the establishment of a scientifically sound debiting and crediting system in ecosystem-based mitigation. One reason is that the impacts of infrastructure projects often affect more than just the ground they occupy. Effects such as habitat fragmentation/isolation, noise, visual disturbance, increased animal mortality, and pollutant emissions are often more difficult to evaluate and quantify than the acres of wetlands filled or habitat disturbed. The concept of ecosystem-based mitigation attempts to take these and other effects into account, and balances gains and losses of ecological functions, benefits, and values.

Building on the REF, ecosystem-based mitigation focuses on the ecosystem-level ecological priorities determined as a "desired future condition." Among others, this may include the protection of specific species, community types, or landscape functions such as habitat connectivity, productivity, or yield. The Wildlife Society's Performance Measures for Ecosystem Management and Ecological Sustainability (Haufler, J.B., et al. 2002) provides a starting point for evaluating specific structures, functions, and processes that can be used to assess ecosystem health and overall condition.

To determine the specific actions needed to achieve goals for an ecosystem, the following questions should be asked:

• Are resources where they need to be for sustainable functions to occur?
• Are ecosystems adequately linked to allow movement of animals and genetic information and to maintain productivity, structure, and diversity?
• Are some communities and habitat types under-represented in a region?

Some regions are beginning to answer these and other questions in efforts to develop ecosystem-based credits and debits. One example is discussed below.

An Interagency Team Develops Ecosystem-Based Credits and Debits

The Carolina Bays Parkway (Parkway) is located in Horry County, South Carolina, home to several rare and endangered species and pristine natural areas. Specifically, the Waccamaw River and Lewis Ocean Bay Natural Heritage Preserves (NHPs), which total more than 20,000 acres and are owned and managed by the South Carolina Department of Natural Resources (SCDNR), are two of the county's last remaining undisturbed natural areas.

The Parkway needed additional interchanges to meet current and anticipated traffic demands. This created the difficult challenge of determining how to accommodate additional demands on the transportation system in ways that sustain the county's natural features. Recognizing that traditional highway mitigation has often been a piecemeal effort that does not effectively support ecosystem objectives, key leaders from several South Carolina agencies collaborated to address the challenge from a landscape level. The interagency team first looked at maps describing where development was planned. They then studied natural resource maps illustrating habitat patterns of species of interest and maps of undisturbed wetlands. The team eventually agreed on a prioritization approach that focused on the protection and enhancement of the wildlife linkage corridors connecting the Preserves while allowing needed transportation projects to move forward.

In 2003, the interagency team, which had searched for opportunities to preserve, enhance, and expand the Lewis Ocean Bay NHP and the wildlife linkage corridor, signed an agreement outlining steps to accomplish these goals. South Carolina DOT (SCDOT) and the FHWA put $2.5 million into an escrow account to be spent on the preservation and expansion of Lewis Ocean Bay and the wildlife linkage zone. This Federal-aid money was agreed upon as partial mitigation for two new interchanges to be added to the Parkway. A management system was also put in place for the funds, with members of the USFWS, SCDNR, USACE, and NOAA Fisheries Service forming an Ecosystem Committee to oversee the expenditure of those funds on projects that will enhance, preserve, or expand the Lewis Ocean Bay NHP and protect the Waccamaw River wildlife linkage corridor. Additionally, SCDOT purchased access control of a public road, which limited growth opportunities in that area and protected some of the land adjacent to the Preserves. SCDOT also invited private landowners to become part of the solution. In exchange for one of the new interchanges on the Parkway, the private landowners are donating to SCDNR a 320-acre tract of land. This tract was a privately owned in-holding within Lewis Ocean Bay NHP that could have been developed.

In the end, all partners agreed to preserve and expand the area's most important ecosystem values while allowing responsible infrastructure growth to occur.

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