Section 2. The Future of Puget Sound: Where are We Going?

The charge is clear: restore the ecological health of Puget Sound by 2020. What is less clear, however, is what future the citizens of the Puget Sound region desire. Understanding what future we want, and what futures are possible, is critical to informing management decisions about complex systems such as Puget Sound, comprised of multiple unpredictable components. The theme of any individual vision of the future may range from particular ecosystem states (e.g., healthy orca populations, clean water) to socio-economic conditions (e.g., thriving ports, efficient and integrated public transportation). However, comprehensive visions of future states require that Puget Sound be considered in the context of a coupled social-ecological system, with the socio-economic system influencing the ecological system, and vice-versa. All components of this complex system are in turn being transformed by driving forces that can be either internal or external to the system. These unpredictable and largely uncontrollable driving forces, for example, climate change, the national and global economies, human desires, behavior and attitudes, each have their own potential trajectories that will help shape the future state of the Puget Sound ecosystem. For example, whether the future climate of Puget Sound is warmer and wetter, or warmer and drier, will certainly shape management strategies aimed at protecting species that use the freshwater streams and rivers in Puget Sound, such as salmon. Describing the future state of Puget Sound, therefore, goes beyond making predictions based on past observed trends in the ecological system and identifying actions that Puget Sound resource managers can implement. Understanding the myriad potential futures of Puget Sound is critical to setting targets aimed at achieving goals for restoring the health of Puget Sound by 2020.

This section will review previous efforts to describe alternate futures for Puget Sound, highlight the trade-offs inherent in these scenarios, particularly in light of drivers generated outside of the Puget Sound ecosystem, and draw connections between future scenarios and management strategies, including the importance of setting targets and deriving quantitative measures of progress. Finally, we suggest directions for continued efforts to describe alternate futures of Puget Sound.

Describing the future state of Puget Sound has been approached in several ways, including using a formal scenario planning process, within the context of a regional planning strategy, using models and GIS (Geographical Information System) tools to map potential changes on the landscape, and setting specific targets for the desired future ecological system. Most of the work has been focused on the nearshore habitats of Puget Sound, with limited consideration of other domains of the ecosystem (e.g., rivers, forests, freshwater wetlands). Each approach described here is one component of what we see as a comprehensive future scenario process, beginning with a declaration of priorities by policy makers, followed by a thorough exploration of the driving forces behind the Puget Sound ecosystem and their potential trajectories, and finally, drawing explicit links (mediated by the driving forces) between potential policy decisions, biophysical states, and their consequences for the ecological system and ecosystem goals. As yet, there is no single “soup-to-nuts” approach to describing a future Puget Sound, though some of the efforts reviewed below are still works in progress.

The Puget Sound Regional Council’s “Vision 2040,” adopted in 2008 and amended in 2009, is essentially a declaration of priorities for the future of Puget Sound by the major policymakers and politicians in the Central Puget Sound region (Puget Sound Regional Council 2009). Vision 2040 describes the growth management, environmental, economic and transportation strategies for the region. It co-prioritizes people, the economy, and the environment, and lists a series of goals and future actions, some of which are supported by existing policy. The document charts a pathway for land development and design, referencing existing land-use development policy (Washington State Growth Management Act) and establishes goals for matching development patterns with human well-being. Regional economic prosperity is a goal to be achieved by implementing a separately-established Regional Economic Strategy (Puget Sound Regional Council 2005). Finally, a multimodal regional transportation system is a priority, “integrating freight, ferries, highways, local roads, transit, bicycling and walking” (Puget Sound Regional Council 2009).

Vision 2040 provides a framework within which regional planning on land use, economic development, and transportation can occur. The strategy explicitly takes into consideration the connectedness of regional planning and the environment. The document outlines goals, actions and implementation strategies for transportation and development, primarily from a policy and planning perspective. The drivers of the ecosystem are policies, which alter the (terrestrial) landscape according to a broad set of guidelines aimed at encouraging density within urban areas and limiting development outside of urban areas, and strengthening public transit and non-motorized transportation without compromising regional economic growth. There is a single vision of an ideal future Puget Sound region, and this document lays the groundwork for achieving that vision.

Summary: Within the context of a comprehensive effort to describe potential futures of Puget Sound, Vision 2040 serves as a statement by the citizens, as represented by their elected officials. Missing from this are more specific statements from the public about their views on, for example, a healthy Puget Sound. However, to date, no comprehensive survey or collection of citizen opinions about the future of Puget Sound exists, and therefore this document is the best proxy we have for gauging broad societal goals and desires. Any description of potential Puget Sound futures should include the public’s desires as assurance that the ecosystem is headed in a direction supported by the public, and therefore this document is useful as one piece in the future scenario process.

In another approach to describing a future Puget Sound, the Puget Sound Nearshore Partnership and the Urban Ecology Research Lab (UERL) produced “Future Scenarios” (2009), which employs a formal scenario-building process to identify the driving forces of change in the Puget Sound ecosystem, and to develop multiple alternative scenarios based on the uncertainty in and interactions between those driving forces. Scenario building is a systematic method that has been applied to coupled social-ecological systems by, for example, the Millennium Ecosystem Assessment (Reid 2006), and aims to generate more flexible approaches to EBM through the incorporation of uncertainty and multiple knowledge types. The fundamental premise is that the future is unknown, and that it is a function of several key factors that interact to create multiple potential future outcomes.

Through a series of visioning exercises with stakeholders and experts on the Puget Sound social-ecological system, two “key” drivers (climate and human behavior/perceptions) and nine “supporting” drivers (demography, development patterns, economy, governance, knowledge/information, natural hazards, public health, and technology/infrastructure) were identified, as were the interactions among them. The “key” drivers represent the most important and uncertain driving forces relevant to the issue, in this case the nearshore ecosystem of Puget Sound. Based on the potential trajectories of the key drivers and their interactions with the supporting drivers, six scenarios were developed. Narratives of each scenario described the prosperity, human attitudes, climate regime, development patterns, governance structure and demographics of a future Puget Sound, primarily as a function of the key drivers, climate and human behavior/perceptions and without drawing explicit links to component of the ecological system. Each narrative was rooted in a storyline, described by society’s worldview, human-nature relationships, and future outlooks (i.e. optimistic vs. pessimistic, or positive about human-nature relationships vs. hostile towards the environment).

The six scenarios spanned a broad range of social and climatic conditions, coupled with resulting effects on the ecological system. For example, in the “Collapse” scenario, climate change manifested as drier and warmer conditions in Puget Sound, and human behavior was self-interested and focused on the near-term. High levels of resource extraction and pollution caused harm to ecosystem function. Poor economic performance and increasing government expenditures led to fewer investments in infrastructure and public services, and eventual out-migration of the population. On the other end of the spectrum, the “Forward” scenario described a future with only limited climate change in Puget Sound and a cooperative social ethic, leading to a proactive approach to environmental issues and higher quality of life. There was increased population and economic growth. There was a greater understanding of the linkages between society and nature, leading to a stronger relationship between residents and their environment.

Summary: “Future Scenarios” gives a very thorough treatment to the socio-eco-political matrix within which the nearshore ecosystem (to which this analysis was limited) exists. Links are drawn between attitudes, economics, politics and climate, and alternative trajectories are explored for each--an important acknowledgment that there is great uncertainty involved in any vision of the future. This approach to fleshing out ecosystem drivers and their trajectories is critical in a comprehensive effort to describe the future of complex social-ecological systems like Puget Sound. The next step of this project is to explicitly link the drivers and scenarios to the ecological constituents and interactions.

The Puget Sound Nearshore Ecosystem Restoration Project (PSNERP) has developed several future scenarios of Puget Sound by coupling the Future Risk Assessment Project (FRAP), the creation of one set of land-use scenarios, with the Puget Sound Ecosystem Portfolio Model (EPM; Labiosa et al. 2009), a suite of models that evaluate the effects of land-use scenarios on nearshore ecosystems. The Puget Sound Nearshore Science Team and scientists from Oregon State University generated land-use scenarios based on three potential directions for land-use policy: status quo, where current trends continue forward; managed growth, which incorporates aggressive policies directing growth into urban areas; and unconstrained growth, which relaxes land-use regulation. Each scenario modulates several parameters governed by growth policy: population distribution, urban and rural development patterns, nearshore development pattern/intensity, and protection of open space. These scenarios were input to a GIS model, generating terrestrial maps of land use/land cover for Puget Sound (Bolte 2009).

The EPM models link land-use patterns generated by policy scenarios to ecosystem state, and therefore analyses can be directed towards specific goals. One such set of links was developed targeting human well-being, one of the six major goals of the Puget Sound Partnership. Using a list of human well-being indicators chosen in consultation with multiple expert groups, explicit connections are drawn between land-use patterns and metrics of human well-being using existing data and models. For example, each land-use scenario developed by FRAP results in some degree of shoreline modification, which is then linked to indicators of human well-being, one example of which is recreational beach use. A statistical model predicts the effects of land-use development on recreational beach use as a function of recreational visit data, demand (based on population density) and access (based on travel cost), each of which is affected by shoreline development.

Summary: The FRAP/EPM approach emphasizes connections between patterns on the landscape, generated through simple policy-driven scenarios, and specific ecosystem states that can be linked to a broader ecosystem or policy goal, in this case human well-being. In the context of a comprehensive future scenario process, this is a critical step that highlights the consequences of individual policy decisions, like land-use development, for ecosystem goals, in this case human well-being. This technique could also be used in conjunction with scenarios that generate ranges of responses by the social-ecological system. For example, to these same land-use policy scenarios could added climate change scenarios that will alter the way the ecological system responses to, for example, shoreline modification. Under warmer, wetter conditions, erosion patterns and the absolute amount of shoreline in Puget Sound may change, both of which will affect recreational beach use. This tool linking changes made on the landscape to ecosystem goals is helpful in charting a path towards ecosystem goals and in predicting the feedbacks of policy decisions.

The Puget Sound Salmon Recovery Plan, in contrast to the above approaches, uses specific targets to describe the future, by establishing regional and watershed-specific abundance and productivity targets for threatened Pacific salmon and bull trout populations. In 1999, Puget Sound Chinook Salmon, Coastal/Puget Sound bull trout and Hood Canal summer chum were listed as threatened under the Endangered Species Act (ESA). Subsequently, a number of independent recovery plans for Puget Sound salmon populations were initiated, and the Puget Sound Salmon Recovery Plan aimed to combine the efforts and strategies of several groups, most notably the Shared Strategy for Puget Sound (Shared Strategy) and NOAA’s National Marine Fisheries Service (Shared Strategy for Puget Sound 2007). The Shared Strategy generates individual watershed targets for salmon populations based on technical models and historic information, setting target ranges for salmon abundance and productivity.

Using these watershed-specific targets, the Salmon Recovery Plan then establishes short- and long-term numerical goals, identifies limiting factors, and offers specific strategies, in some cases at the scale of individual tributaries, for reaching those goals. For example, the Lake Washington/Cedar River/Lake Sammamish Chinook salmon population’s 10-year goal is 1,600 spawners, and the long-term goal is between 2,000-12,000 spawners, allocated among the different water bodies. The major limitations to achieving increases in productivity and abundance include altered hydrology, loss of riparian vegetation, lack of woody debris, and high temperatures and pollution levels. The strategies identified to achieve the abundance and productivity goals include protecting and managing upper watersheds, restoring stream habitat, improving lake habitat and reducing the impacts of urban development. Individual actions are recommended for specific tributaries or water bodies.

The Shared Salmon Recovery Plan defines the future in terms of specific targets for the ecological system (salmon abundance and productivity), identifies threats to achieving those targets, and lays out strategies and actions for addressing the threats. While it does not offer alternate future scenarios, it outlines an adaptive management approach to investigate and incorporate sources of uncertainty such as climate change, interactions between wild and hatchery fish, effects of poor freshwater and marine water quality, and nearshore habitat processes.

Summary: This approach is one of few that specifically identifies targets for Puget Sound ecosystem goals. In the context of a complete results chain approach to achieving a healthy Puget Sound, setting targets is critical for understanding the trade-offs between different goals (see below). In the context of a comprehensive future scenario process for Puget Sound, targets represent concrete objectives against which results from statistical models (e.g., EPM) and potential future states of driving forces can be compared. For example, under a warmer, wetter climate, with a population focused on near-term objectives, a flat local economy and status-quo land use policies, can the stated salmon productivity targets be reached for each watershed? Under which scenarios are the targets achievable? Asking these complex questions highlights the need for a comprehensive effort to describe the future Puget Sound.

The above review of four very distinct efforts to describe a future Puget Sound highlights what is needed, and what is missing, in a comprehensive future scenario process. Comprehensive visions of a future Puget Sound will chronicle the political motivation and citizens’ desired state; explore the uncertainty in the driving forces of the social-ecological system, including climate change; draw explicit links between the drivers and the ecological state; and develop targets for future state characteristics based on existing data and models. “Vision 2040” provides the best measure we have of the public’s vision for the future of Puget Sound; however, this description is missing specific references to the ecological system which could help management predict the public’s response to or support for certain decisions or trade-offs. Characterizing the major uncertainties in the system and offering potential future scenarios based on these is a crucial step in adequately matching ecosystem goals with strategies and actions, and “Future Scenarios” is a very thorough treatment of the driving forces behind this uncertainty. Any thorough approach to describing potential futures must incorporate climate scenarios, as well as the key socio-economic drivers in the system. If these driving forces can be incorporated into the model-based scenarios and on-the-ground biophysical depictions of policy decisions (effectively exemplified by FRAP and EPM), then more accurate assessments of alternate management strategies will be possible. This is a formidable task, and the work reviewed above contributes towards that end. A thorough effort to describe a future Puget Sound (i.e., Where are we going?) is a partner to larger effort in this document, developing indicators for the system (Are we there yet?).

Among other marine ecosystem management programs in North America, the most common approach to defining the future is akin to the FRAP/EPM method described above: develop predictions for future ecological states based on existing information, and specifically, generate a few land-use scenarios based on policy decisions governing development, growth management, pollution controls, transportation and/or conservation, and connect the resulting landscape patterns to ecological function, such as nutrient or sediment inputs (Boesch and Greer 2003, Roberts et al. 2009). Less common is a thorough examination of the socioeconomic and climate drivers of ecosystem dynamics, as in the UERL/PSNERP “Future Scenarios.” However, even in cases where the drivers of the ecosystem are well described and incorporated into future scenarios, their utility is limited by the extent to which linkages are drawn between drivers, ecological state, and goals or targets.

Most future scenario-building efforts (including several reviewed above), lack an explicit treatment of the trade-offs required to successfully arrive at a desired future state. Moving from citizen desires to ecosystem reality requires confronting trade-offs among multiple goals. For example, the U.S. Government’s roadmap for restoring the Louisiana-Mississippi Coast Ecosystem acknowledges that stakeholders must “jointly evaluate trade-offs that will likely be necessary” to meet the multiple goals of ecosystem function, resilience, economics and climate adaptation (“Roadmap” 2010). Such trade-offs are cast in sharp relief when considering the tension between local economic prosperity, the global economy and water quality in Puget Sound. The Ports of Seattle and Tacoma together comprise the third busiest container port in the U.S. (American Association of Port Authorities, 2008), and a large proportion of the Puget Sound regional economy relies on the import and export of goods through the ports. A growing demand for imports and exports through Puget Sound ports, generated by a flourishing global economy, could increase shipping traffic. The Ports of Seattle and Tacoma are already challenged to meet port productivity goals as well as water quality requirements, and a rise in traffic through the Ports would exacerbate that particular challenge, if not necessitate additional construction along Puget Sound shorelines. Both increased shipping traffic and increased hardening of shorelines negatively impact Puget Sound marine species, food webs, habitat, water quality – each a PSP goal. Other trade-offs likely to emerge include those between population increase, development pressures and habitat protection; population increase, agricultural demands and minimum stream flows; and economic prosperity, shipping traffic and invasive species control. As these examples highlight, achieving human well-being and ecological function without sacrificing economic prosperity in Puget Sound will require some compromises.

In some cases, thorough consideration of trade-offs is not possible owing to the absence of targets--the desired future numeric value for an ecosystem indicator. In large part, quantifiable targets related to the state of the Puget Sound ecosystem are missing from future scenario efforts (one major exception to this is the Shared Salmon Recovery Plan). In the absence of targets, the assessment of progress and a complete understanding of trade-offs are elusive. Establishing targets forces confrontation with trade-offs; without targets, the definition of “success” – and the route to get there – is flexible. Furthermore, in the context of a future scenario process, evaluation of scenarios is hampered without targets. Full evaluation of trade-offs, in turn, involves describing the human drivers of ecosystem change, such as behavior and perception, which highlights the importance of including these driving forces in future scenario processes.

One means of addressing trade-offs and targets is management strategy evaluation (MSE), a conceptual framework that facilitates testing and comparison of different management strategies designed to achieve specified management goals (Sainsbury et al. 2000). The MSE process is analogous in many ways to the approach employed by the FRAP/EPM effort described previously. Born from the concepts of adaptive management of resources (Walters 1986) and management procedure evaluation (Magnusson and Stefansson 1989), MSE is an analytical process that follows six basic steps:

• Policy objectives, target values, and performance measures (measures of success) for important resources are defined and quantified.
• A management strategy is designed to achieve the objectives.
• The strategy is implemented in an operating model that simulates ecosystem processes relevant to the resources of interest. The model may be simple or complex, depending on the underlying questions.
• A simulated monitoring program draws imperfect data from the operating model.
• An assessment model is run to determine the effect of management on indicator variables measured by the simulated monitoring program. The levels of the indicators are compared to the pre-determined target values; the difference is a measure of performance.
• Depending on the outcome of the assessment, decision rules will be activated that either continue or adjust the management strategy, until the objective is met.

This process is repeated for multiple management strategy alternatives, which allows comparison of different strategies—in terms of both successes (positive performance measures; rapid progress) and weaknesses (negative performance measures, slow progress)—in attaining desirable future states. In this way, the potential effectiveness and the potential trade-offs of the strategies are understood.

Several operating models that are available or in development could support MSE of alternate Puget Sound futures. Some available models focus on aquatic and marine issues such as municipal water supply (Wiley and Palmer 2008) and the relationship between terrestrial activities and marine biogeochemistry (e.g., Roberts et al. 2005). Others focus on terrestrial issues such as land use and urbanization impacts on species diversity (Hepinstall et al. 2008). Several models in development simulate the structure of the marine food web (e.g., the Ecopath with Ecosim model of Central Puget Sound (Harvey et al. 2010)), and are well-suited to forecast trade-offs between different resources or stakeholders as a result of simulated management actions. Continued development of such models is a high priority.

Future scenarios are a critical tool for informing and refining conservation strategies. The PSP has adopted the Open Standards for Practice of Conservation framework for performance management. A key component of the Open Standards is “results chains,” which map management strategies to their expected outcome (e.g., reduction of a threat) and their impact on key components of the ecosystem (Figure 1). An individual results chain is comprised of multiple components: a goal is linked to a strategy, such as a policy decision, for achieving that goal; associated with each strategy are one or more outcomes of that strategy; a second outcome or set of outcomes describes an expected change in the ecosystem threat; the threat outcome is linked to an ecological impact, which relates to the goal (Figure 1). In the context of the Open Standards, alternate future scenarios, whether describing possible trajectories of external drivers (e.g., climate change, human attitudes), policy outcomes (e.g., Shoreline Management Act amendments), or the state of the economy, can be incorporated into results chains by generating ranges for outcomes or impacts, rather than single values. In this way, alternate futures help set realistic targets for desired ecological states.

Figure 1. An example of a modified results chain, incorporating the influence of future scenarios of drivers (orange diamonds) on links in the chain, adding an example of an indicator (triangle) and showing where a target would be included. The effect of future scenarios on a results chain is shown here by overlaying a distribution of possible conditions (grey curves) for outcomes or impacts where they are potentially influences by future conditions of external drivers. Original chain from Puget Sound Partnership 2009a.

To illustrate the utility of future scenarios in the results chain framework, we use an example where a set of land protection actions from the Puget Sound Partnership’s Action Agenda is aggregated into a results chain describing regulatory strategies for protecting and enhancing ecosystem components. One sub-chain focuses on a strategy to amend the Shoreline Management Act (SMA) by requiring conditional use permits for land development (Figure 1), with the ultimate objective of converting less habitat, which would positively impact many components of the ecosystem, including salmon (Puget Sound Partnership 2009a). The first “if...then” step in this sub-chain is that if the SMA is amended, then the revised version will be enacted. This initial step requires approval by voters, through their elected legislative representatives, and is therefore subject to the influence of human attitudes and perceptions. Surveys of Puget Sound citizens and stakeholders have indicated that, in general, people do not think Puget Sound is alarmingly unhealthy, and they are disinclined to make major sacrifices to protect and restore the ecosystem (Fennessy 2006). Therefore, there is some uncertainty, a function of human attitudes, about whether this legislation would be approved, and that uncertainty is described by a range of potential policy outcomes, rather than a single deterministic outcome. In addition, assuming all the outcomes in the results chain are achieved, and less habitat is converted by development, climate change can still influence the abundance and productivity of salmon populations through other mechanisms, and the impact of regulation changes on salmon will be mediated by the potential influence of climate change. Therefore, the goal “Salmon” is represented as a range of possible salmon populations, rather than a single value. This example illustrates the role of future scenarios in developing performance measures and outcomes for conservation plans.

We have also modified the results chain by adding in indicators, which are connected to the Impact (Goal) – in this case, the indicator of “Salmon” is “Chinook returns.” Associated with each indicator, also, would be a target, in this case, likely watershed-specific targets for Chinook salmon returns, such as those generated by the Shared Salmon Strategy.

Our review of the few efforts to envision a future Puget Sound suggests considerable room for future work. While there is clear agreement that the future state of Puget Sound should be different than it is now, the region lacks a lucid vision of the desired state of the coupled human-ecological system. The strong links between human activities and nearshore ecosystem components have resulted in most of the effort being direct towards this domain; however, there is no doubt that future scenarios for the whole of Puget Sound - from “sea to summit”- are required. Externalities of human and natural origin are important driving forces in this coupled system and should be included in analyses of scenarios. And, ultimately, these scenarios are most useful if they identify trade-offs and develop means for operating along the axes between trade-offs. The lack of management targets for most components of the Puget Sound ecosystem allows managers and policy makers to avoid confronting many trade-offs and thus encourages somewhat narrow (e.g., single ecosystem domains) or vague and ill-defined visions of the future. However, our review reveals that the foundation to generate scenarios of a future Puget Sound is in place. As the efforts described here continue and expand and new endeavors begin, we expect more comprehensive visions of Puget Sound’s possible future to emerge.

Table 1. Summary of final scenarios generated by “Future Scenarios”; adapted from Table 6.1 in UERL 2009.

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