Projects

Mediating the impacts of local flooding in the Mississippi-Alabama coastal region through green infrastructure plan evaluation

End Date: 01/31/2020

Abstract

Urban ecosystems are increasingly at risk of being devastated by an ever-expanding city. The rapid expansion of urban areas in these coastal communities will likely lead to the conversion of undeveloped land into impervious surfaces, which degrades ecosystems, exacerbates flooding, and increases the amount and velocity of stormwater runoff. In order to minimize these negative impacts, some local governments have adopted “green infrastructure” plans and strategies in order to conserve and protect their natural resources, such as greenways, wetlands, and open spaces. This proposed research aims to:

  1. Identify communities that have engaged in green infrastructure planning in the Mississippi-Alabama coastal region;
  2. Identify best practices among those communities; and
  3. Identify landscape patterns that should be protected with the goal of transferring this knowledge to other Mississippi-Alabama coastal communities.

This research will help communities become more resilient to the impact of climate change by mediating heat island effects and flood damages, while promoting physical activities of residents through well-connected open spaces and landscapes. Both quantitative and qualitative evidence-based evaluation methods will be used to provide an indepth understanding of current green infrastructure planning practices and their outcomes. The proposed research will improve the quality of coastal communities’ plans, and the communities’ quality of life, by incorporating key concepts of green infrastructure planning in to their planning process and reducing flooding events. It will also promote awareness of and provisions for green infrastructure plans in rapidly growing jurisdictions as to avoid excessive stormwater damage. This research will additionally provide practical tools for governmental leaders and planners to assess their current green infrastructure, determine future needs, and develop strategies for closing this gap. 

Objectives

Objectives to identify municipalities in the Mississippi-Alabama coastal region that have incorporated green infrastructure strategies:

To collaborate with our regional partners, the Gulf Coast Regional Planning Commission (Mississippi) and the South Alabama Regional Planning Commission (Alabama), to identify which local coastal municipalities within their Metropolitan Planning Organization (MPO) have engaged in green infrastructure planning. 

  1. To develop a scorecard of key indicators of green infrastructure planning. 
  2. To evaluate, per the scorecard, the comprehensive plans of the selected cities in order to identity the degree to which they have incorporated green infrastructure strategies into their plans. 
  3. To identify the specific green infrastructure strategies stated in these city’s plans, with an emphasis on examining regional-scale green infrastructure strategies. 

Objectives to test whether the plans’ green infrastructure implementation strategies effect flood and stormwater runoff mitigation:

  1. To evaluate the impacts of plan implementation on the actual stormwater runoff attenuation.
  2. To test the various strategies’ effect on flood and stormwater runoff mitigation by comparing plan quality scorecard scores with actual stormwater runoff. 

Objectives to collaborate with local and regional partners in order to identify best practices and share knowledge among the partners and with other coastal cities:

  1. To establish an advisory board comprised of local and regional planning partners, including the Gulf Coast Regional Planning Commission (Mississippi) and the South Alabama Regional Planning Commission (Alabama).
  2. To identify best practices in green infrastructure implementation, their incorporation in comprehensive plans, and their implementation.
  3. To conduct a survey of city and county planners in order to collect data on planning capacity (e.g., budget, leadership, and responsibility) and availability of resources.
  4. To share the knowledge obtained from this research among the regional and local partners through partner meetings and to disseminate it to larger audiences through publications.

Methodology

Both quantitative and qualitative evidence-based evaluation methods will be used to provide an in-depth understanding of current green infrastructure planning practices and their outcomes. The proposed research has three main phases that will allow hypotheses testing: 

  1. The researchers will examine how well the comprehensive plans of the selected cities have incorporated green infrastructure planning strategies. The researchers will develop, based on the existing research, a scorecard of key indicators of green infrastructure planning, in which they will use to analyze the comprehensive plans and information on capital investment programs. Per this scorecard, the plans will be evaluated according to a “breadth score” (i.e. the range of green infrastructure indicators), and a “depth score” (i.e. the level of detail included in the various strategies).
  2. An explanatory model will be developed and tested based on past research in order to identify which specific factors encourage municipalities to integrate green infrastructure concepts in their comprehensive plans. Planning organization’s capacities will be observed along with other factors, including socio-economic characteristics and the risk of stormwater hazards. These factors are assumed to influence the overall plan quality score obtained at the first phase. In-depth surveys of city planners will also be used in order to collect detailed information on their planning capacity (e.g., budget, leadership, and responsibility) and resources in coastal areas. 
  3. The researchers will examine the impacts of plan implementation on the actual stormwater runoff attenuation. The outcomes of plan implementation will be measured by the spatial configuration (e.g., size, shape, isolation, and connectivity) of open and green spaces (i.e. landscape) and of development. 

Rationale

Urban ecosystems are increasingly at risk of being devastated by an ever-expanding city. The rapid expansion of urban areas in these coastal communities will likely lead to the conversion of undeveloped land into impervious surfaces, which can increase the risk of ecosystem degradation and flooding damage. To minimize these negative impacts, local governments have adopted “green infrastructure” plans and strategies, which conserve natural resources such as greenways and wetlands. This research aims to:

  1. Identify which communities have engaged in green infrastructure planning in the Mississippi-Alabama coastal region;
  2. Identify best practices among those communities; and
  3. Identify landscape patterns that should be protected with the goal of transferring this knowledge.

It will test the following hypotheses:

  1. Municipalities in the Mississippi-Alabama coastal region have not integrated, or have integrated on a limited basis, green infrastructure planning strategies into their comprehensive plans. 
  2. High levels of planning capacity will be positively associated with high levels of green infrastructure incorporation. 
  3. Municipalities that ranked high on the green infrastructure plan quality scorecard will have more green spaces and landscape patterns that connected, clustered, and diverse.  
  4. Municipalities that protect the integrity of green infrastructure between developed areas have a greater capacity to mitigate local flooding and provide quality of life recreational resources to local inhabitants.

This research will help communities become more resilient to the impact of climate change by mediating heat island effects and flood damages, while promoting physical activities of residents through well-connected open spaces and landscapes. This research offers a new approach to framing the role of open spaces/landscape patterns within a multifunctional green infrastructure in an urban setting. This research can be used to develop urban planning models flexible enough to accommodate new development at different spatial settings while protecting urban ecosystems for recreation and the environment.