Residential property value impacts of floodplain buyouts in Charlotte, North Carolina.

Floodplain buyouts are an increasingly common policy for mitigating flood risk. Recent research has explored the costs of buyouts and their impacts on municipal finance and tax base. However, little work has explored the effects of buyouts on surrounding residential land values, an aspect that could contribute to the extensive literature on the land value impacts of urban land uses, including open space and ecological restoration. This study evaluates the residential land value impacts of buyouts in Mecklenburg County, North Carolina (USA), an area with extensive, municipally- and federally-funded buyouts (n = 348). Using a quasi-experimental research design that matches treatment parcels (near buyouts) to control parcels to isolate the causal impacts of buyouts, we find that buyouts are responsible for weak increases (p<0.1) in the area-normalized sales values ($/ft2) of neighboring (within 0.15 km) single-family residential properties. We additionally find positive - but also weak - sales value relationships with (1) buyouts that have programmed post-buyout land uses, such as parks or other recreation areas (USD$25.46/ft2 [$274.05/m2] when 0.15-0.2 km from buyout; p<0.05), and (2) the average age of proximal buyouts ($0.34/ft2 [$3.66/m2] within 0.1-0.15 km; $0.30/ft2 [$3.23/m2] within 0.15-0.20 km; both p<0.01). Our results suggest that post-buyout land uses may have impacts on local tax base and should play a larger part in municipal buyout decisions.

Assessing the size and growth of the US wetland and stream compensatory mitigation industry.

Interest has focused on quantifying the size and scope of environmental markets, particularly those that offset ecosystem impacts or restore natural infrastructure to improve habitat or promote clean air and water. In this paper, we focus on the US wetland and stream compensatory mitigation market, asking: what types of firms make up the mitigation "industry"? What are the economic impacts-i.e., the "size"-of the mitigation industry? How has this industry changed over time? We present the results of a national survey of mitigation firms and construct an input-output model of the industry's economic impacts and employment. We also develop a comparative, 2014 model of the industry using data from a previous study of the broader, ecological restoration economy. Our findings suggest that the (2019, pre-COVID) mitigation industry collects annual revenues (direct economic impacts) in excess of $3.5 billion, which, along with additional indirect (supply chain) and induced (spillover) economic impacts, combine to over $9.6 billion in total output and support over 53,000 total jobs. We estimate 2014-2019 growth of ~35.2 percent in revenues, ~32.6 percent in total economic impacts, and a compound annual growth rate (CAGR) of 5.25%. This places the mitigation industry within the range of other, well-established industries within the technical services sector. We suggest establishing North American Industry Classification System (NAICS) codes specifically for ecological restoration and mitigation firms, an essential step in generating accurate and consistent employment estimates in the future, particularly at sub-national geographic scales.

Assessing the full costs of floodplain buyouts.

Given projected increases in flood damages, managed retreat strategies are likely to become more widespread. Voluntary buyouts, where governments acquire flood-damaged properties and return the sites to open space, have been the primary form of federally funded retreat in the USA to date. However, little attention has been paid to the cost structure of buyout projects. Using a transaction cost framework, we analyze the costs of activities that comprise floodplain buyouts. Federal data do not distinguish transaction costs, but they do suggest that the cost of purchasing properties often accounts for 80% or less of total project costs. Through a systematic review (n = 1103 publications) and an analysis of government budgets (across n = 859 jurisdiction-years), we find limited sources with relevant cost information, none of which reports transaction costs. The absence of activity-level cost data inhibits more targeted policy reform to support community-driven and efficient buyout programs. Better data collection and reporting can inform more impactful and equitable buyout policy.

Does removal of federal subsidies discourage urban development? An evaluation of the US Coastal Barrier Resources Act.

Urban development relies on many factors to remain viable, including infrastructure, services, and government provisions and subsidies. However, in situations involving federal or state level policy, development responds not just to one regulatory signal, but also to multiple signals from overlapping and competing jurisdictions. The 1982 U.S. Coastal Barrier Resources Act (CoBRA) offers an opportunity to study when and how development restrictions and economic disincentives protect natural resources by stopping or slowing urban development in management regimes with distributed authority and responsibility. CoBRA prohibits federal financial assistance for infrastructure, post-storm disaster relief, and flood insurance in designated sections (CoBRA units) of coastal barriers. How has CoBRA's removal of these subsidies affected rates and types of urban development? Using building footprint and real estate data (n = 1,385,552 parcels), we compare density of built structures, land use types, residential house size, and land values within and outside of CoBRA units in eight Southeast and Gulf Coast states. We show that CoBRA is associated with reduced development rates in designated coastal barriers. We also demonstrate how local responses may counteract withdrawal of federal subsidies. As attention increases towards improving urban resilience in high hazard areas, this work contributes to understanding how limitations on infrastructure and insurance subsidies can affect outcomes where overlapping jurisdictions have competing goals.

A scoping review of simulation modeling in built environment and physical activity research: Current status, gaps, and future directions for improving translation.

Existing reviews have suggested that simulation studies of physical activity and environments are an emerging area, but none have explored findings in this area systematically. We used a scoping review framework to assess the use of simulation modeling to inform decision-making about built environment influences on physical activity. A systematic literature search was conducted in multiple databases in January 2018. Sixteen articles met the inclusion criteria. The studies evaluated interventions and features that were related to neighborhood safety (crime or traffic), active transportation, land use design, and walking and biking infrastructure. All of the studies focused on urban areas and most considered heterogeneity of outcomes based on local context. The majority of studies (70%) did not appear to have engaged or been used by practitioners or policy-makers to inform real-world decisions. There has been a growth of simulation modeling studies, but there remain gaps. The studies evaluated built environment interventions that have been recommended by expert panels, but more were of interventions related to active transportation; few considered recommended interventions to support recreational activity. Furthermore, studies have all focused on urban settings and there is a need to consider non-urban settings and how heterogeneity could reduce or exacerbate health disparities. More work to involve and evaluate practices for engaging stakeholders in model development and interpretation is also needed to overcome the translation of simulation research to practice gap, and realize its potential impact on the built environment and physical activity.

Purpose, processes, partnerships, and products: four Ps to advance participatory socio-environmental modeling.

Including stakeholders in environmental model building and analysis is an increasingly popular approach to understanding ecological change. This is because stakeholders often hold valuable knowledge about socio-environmental dynamics and collaborative forms of modeling produce important boundary objects used to collectively reason about environmental problems. Although the number of participatory modeling (PM) case studies and the number of researchers adopting these approaches has grown in recent years, the lack of standardized reporting and limited reproducibility have prevented PM's establishment and advancement as a cohesive field of study. We suggest a four-dimensional framework (4P) that includes reporting on dimensions of (1) the Purpose for selecting a PM approach (the why); (2) the Process by which the public was involved in model building or evaluation (the how); (3) the Partnerships formed (the who); and (4) the Products that resulted from these efforts (the what). We highlight four case studies that use common PM software-based approaches (fuzzy cognitive mapping, agent-based modeling, system dynamics, and participatory geospatial modeling) to understand human-environment interactions and the consequences of ecological changes, including bushmeat hunting in Tanzania and Cameroon, agricultural production and deforestation in Zambia, and groundwater management in India. We demonstrate how standardizing communication about PM case studies can lead to innovation and new insights about model-based reasoning in support of ecological policy development. We suggest that our 4P framework and reporting approach provides a way for new hypotheses to be identified and tested in the growing field of PM.

A geospatial analysis of land use and stormwater management on fecal coliform contamination in North Carolina streams.

Although non-point source (NPS) pathogen pollution is a leading cause of stream impairment in the United States, the sources of NPS pollution are often difficult to ascertain. While previous studies have employed land use regression methods to develop a greater understanding of the sources and dynamics of microbial NPS pollution, little work has explicitly considered the effects of local, state, and federal stormwater management policies on water quality across multiple watersheds or at larger spatial scales. How do land use and stormwater management efforts collectively influence fecal coliform (FC) levels at a regional or multiple-watershed scale? We construct a unique spatial regression model of stream FC pollution (n=327 monitoring stations) throughout the state of North Carolina (USA), incorporating both land cover and urban development variables. We then use a subset of our data (nbmp=80 monitoring stations) to incorporate local stormwater control measures and stormwater management policies. Results demonstrate that the inclusion of policy and management variables improves the explanatory capacity for FC levels (R2=0.4412 versus R2=0.5323). Locally, this model can be used to better target stream restoration and water quality mitigation actions and investments, as well as help to predict FC levels at unmonitored locations throughout North Carolina's stream network. More generally, the novel structure of this model can also help examine the large-scale effects of stormwater regulations on surface water pathogen levels, helping researchers and planners better predict water quality in the absence of extensive monitoring station data.

Estimating the Size and Impact of the Ecological Restoration Economy.

Domestic public debate continues over the economic impacts of environmental regulations that require environmental restoration. This debate has occurred in the absence of broad-scale empirical research on economic output and employment resulting from environmental restoration, restoration-related conservation, and mitigation actions - the activities that are part of what we term the "restoration economy." In this article, we provide a high-level accounting of the size and scope of the restoration economy in terms of employment, value added, and overall economic output on a national scale. We conducted a national survey of businesses that participate in restoration work in order to estimate the total sales and number of jobs directly associated with the restoration economy, and to provide a profile of this nascent sector in terms of type of restoration work, industrial classification, workforce needs, and growth potential. We use survey results as inputs into a national input-output model (IMPLAN 3.1) in order to estimate the indirect and induced economic impacts of restoration activities. Based on this analysis we conclude that the domestic ecological restoration sector directly employs ~ 126,000 workers and generates ~ $9.5 billion in economic output (sales) annually. This activity supports an additional 95,000 jobs and $15 billion in economic output through indirect (business-to-business) linkages and increased household spending.

Optimal advanced credit releases in ecosystem service markets.

Ecosystem service markets are popular policy tools for ecosystem protection. Advanced credit releases are an important factor affecting the supply side of ecosystem markets. Under an advanced credit release policy, regulators give ecosystem suppliers a fraction of the total ecosystem credits generated by a restoration project before it is verified that the project actually achieves the required ecological thresholds. In spite of their prominent role in ecosystem markets, there is virtually no regulatory or research literature on the proper design of advanced credit release policies. Using U.S. aquatic ecosystem markets as an example, we develop a principal-agent model of the behavior of regulators and wetland/stream mitigation bankers to determine and explore the optimal degree of advance credit release. The model highlights the tension between regulators' desire to induce market participation, while at the same time ensuring that bankers successfully complete ecological restoration. Our findings suggest several simple guidelines for strengthening advanced credit release policy.

The land value impacts of wetland restoration.

U.S. regulations require offsets for aquatic ecosystems damaged during land development, often through restoration of alternative resources. What effect does large-scale wetland and stream restoration have on surrounding land values? Restoration effects on real estate values have substantial implications for protecting resources, increasing tax base, and improving environmental policies. Our analysis focuses on the three-county Raleigh-Durham-Chapel Hill, North Carolina region, which has experienced rapid development and extensive aquatic ecological restoration (through the state's Ecosystem Enhancement Program [EEP]). Since restoration sites are not randomly distributed across space, we used a genetic algorithm to match parcels near restoration sites with comparable control parcels. Similar to propensity score analysis, this technique facilitates statistical comparison and isolates the effects of restoration sites on surrounding real estate values. Compared to parcels not proximate to any aquatic resources, we find that, 1) natural aquatic systems steadily and significantly increase parcel values up to 0.75 mi away, and 2) parcels <0.5 mi from EEP restoration sites have significantly lower sale prices, while 3) parcels >0.5 mi from EEP sites gain substantial amenity value. When we control for intervening water bodies (e.g. un-restored streams and wetlands), we find a similar inflection point whereby parcels <0.5 mi from EEP sites exhibit lower values, and sites 0.5-0.75 mi away exhibit increased values. Our work points to the need for higher public visibility of aquatic ecosystem restoration programs and increased public information about their value.

Risk and markets for ecosystem services.

Market-based environmental regulations (e.g., cap and trade, "payments for ecosystem services") are increasingly common. However, few detailed studies of operating ecosystem markets have lent understanding to how such policies affect incentive structures for improving environmental quality. The largest U.S. market stems from the Clean Water Act provisions requiring ecosystem restoration to offset aquatic ecosystems damaged during development. We describe and test how variations in the rules governing this ecosystem market shift risk between regulators and entrepreneurs to promote ecological restoration. We analyze extensive national scale data to assess how two critical aspects of market structure - (a) the geographic scale of markets and (b) policies dictating the release of credits - affect the willingness of entrepreneurs to enter specific markets and produce credits. We find no discernible relationship between policies attempting to ease market entry and either the number of individual producers or total credits produced. Rather, market entry is primarily related to regional geography (the prevalence of aquatic ecosystems) and regional economic growth. Any improvements to policies governing ecosystem markets require explicit evaluation of the interplay between policy and risk elements affecting both regulators and entrepreneurial credit providers. Our findings extend to emerging, regulated ecosystem markets, including proposed carbon offset mechanisms, biodiversity banking, and water quality trading programs.

Land use planning and social equity in North Carolina's compensatory wetland and stream mitigation programs.

The U.S. Clean Water Act requires compensatory mitigation for wetland and stream damage through restoration of damaged aquatic ecosystems. We evaluate the North Carolina's Ecosystem Enhancement Program (EEP), a state agency responsible for compensatory mitigation. We compare communities gaining and losing aquatic resources during mitigation, finding new types of socioeconomic disparities that contradict previous studies of mitigation program behavior. We find average distances between impact and mitigation sites for streams (43.53 km) and wetlands (50.3 km) to be larger in North Carolina than in off-site mitigation programs in other regions previously studied. We also find that aquatic resources in the State are lost from urbanized areas that are more affluent, white, and highly educated, and mitigated at sites in rural areas that are less affluent, less well educated, and have a higher percentage of minorities. We also analyze the relationship between urban growth indicators and EEP accumulation of compensation sites. Growth indicators and long-term population projections are uncorrelated with both projected transportation impacts and advance mitigation acquired by the EEP, suggesting that growth considerations can be more effectively incorporated into the EEP's planning process. We explore the possibility that spatial mismatches could develop between watersheds that are rapidly growing and those that are gaining mitigation. We make recommendations for ways that regulators incorporate growth indicators into the mitigation planning process.

A case study of form-based solutions for watershed protection.

Despite an array of policies at the federal and state level aimed at regulating stormwater discharges, engineered solutions enforced by local governments often fall short of meeting water quality standards. Although the implications of land use planning and development regulations are important for stormwater management, they are often overlooked as critical initial steps to improving water quality. This study explores the role of 'form-based' regulations as tools for achieving urban planning and water quality objectives. Form-based codes are a new generation of development codes aimed at regulating urban development based on urban form and density, rather than land use. We present an exploratory case study of the feasibility of form-based codes in the Jordan Lake Watershed in North Carolina, a rapidly growing region where fragmented local governments face stringent nutrient reduction standards under new state regulations. Through program analysis and interviews, we explore the viability of form-based codes for reducing development impacts on Jordan Lake's water quality. We consider the legal feasibility of code enforcement, regional and local barriers and opportunities, and implementation given existing regulatory frameworks. Our findings suggest that high quality information and data modeling are foundational to gaining support for a consensus agreement on the sources and degree of water quality impairment. Furthermore, implementing form-based solutions for water quality is greatly aided by (1) experienced regional planning bodies that have regulatory authority, and (2) local governments whose staff are experienced in implementing complex development ordinances, reviewing architectural renderings, and communicating development requirements with the public and developers.

Landscape characteristics of a stream and wetland mitigation banking program.

In the United States, stream restoration is an increasing part of environmental and land management programs, particularly under the auspices of compensatory mitigation regulations. Markets and regulations surrounding stream mitigation are beginning to mirror those of the well-established wetland mitigation industry. Recent studies have shown that wetland mitigation programs commonly shift wetlands across space from urban to rural areas, thereby changing the functional characteristics and benefits of wetlands in the landscape. However, it is not yet known if stream mitigation mirrors this behavior, and if so, what effects this may have on landscape-scale ecological and hydrological processes. This project addresses three primary research questions. (1) What are the spatial relationships between stream and wetland impact and compensation sites as a result of regulations requiring stream and wetland mitigation in the State of North Carolina? (2) How do stream impacts come about due to the actions of different types of developers, and how do the characteristics of impacts sites compare with compensation sites? (3) To what extent does stream compensation relocate high-quality streams within the river network, and how does this affect localized (intrawatershed) loss or gain of aquatic resources? Using geospatial data collected from the North Carolina Division of Water Quality and the Army Corps of Engineers' Wilmington District, we analyzed the behavior of the North Carolina Ecosystem Enhancement Program in providing stream and wetland mitigation for the State of North Carolina. Our results suggest that this program provides mitigation (1) in different ways for different types of permittees; (2) at great distances (both Euclidean and within the stream network) from original impacts; (3) in significantly different places than impacts within watersheds; and (4) in many cases, in different watersheds from original impacts. Our analysis also reveals problems with regulator data collection, storage, and quality control. These results have significant implications given new federal requirements for ecological consistency within mitigation programs. Our results also indicate some of the landscape-scale implications of using market-based approaches to ecological restoration in general.

Determinants of spatial and temporal patterns in compensatory wetland mitigation.

Development projects that impact wetlands commonly require compensatory mitigation, usually through creation or restoration of wetlands on or off the project site. Over the last decade, federal support has increased for third-party off-site mitigation methods. At the same time, regulators have lowered the minimum impact size that triggers the requirement for compensatory mitigation. Few studies have examined the aggregate impact of individual wetland mitigation projects. No previous study has compared the choice of mitigation method by regulatory agency or development size. We analyze 1058 locally and federally permitted wetland mitigation transactions in the Chicago region between 1993 and 2004. We show that decreasing mitigation thresholds have had striking effects on the methods and spatial distribution of wetland mitigation. In particular, the observed increase in mitigation bank use is driven largely by the needs of the smallest impacts. Conversely, throughout the time period studied, large developments have rarely used mitigation banking, and have been relatively unaffected by changing regulatory focus and banking industry growth. We surmise that small developments lack the scale economies necessary for feasible permittee responsible mitigation. Finally, we compare the rates at which compensation required by both county and federal regulators is performed across major watershed boundaries. We show that local regulations prohibiting cross-county mitigation lead to higher levels of cross- watershed mitigation than federal regulations without cross-county prohibitions. Our data suggest that local control over wetland mitigation may prioritize administrative boundaries over hydrologic function in the matter of selecting compensation sites.