Objective 2.4:

Integrate nature-based solutions into infrastructure planning processes and implementation.

The Need

Nature-based solutions in the built environment can be valuable tools for flood mitigation and stormwater management, in addition to preservation of larger tracts of open space. Nature-based solutions, which are defined in the Regional Vision to include green infrastructure, can be used to replace traditional “gray” infrastructure with vegetated or permeable surfaces. When used in this way, these approaches retain and filter stormwater where it falls rather than relying on built systems to convey stormwater elsewhere.^{See footnote 1} In addition to stormwater management, there are many co-benefits to including nature-based solutions into planning and development. These include environmental benefits, such as filtering water pollutants, improving air quality, sequestering carbon, and providing habitat.^{See footnote 2} They also provide important social and health benefits, such as reducing urban heat, providing recreational opportunities, and improving mental health and well-being through access to nature.^{See footnote 3} Local governments can also realize cost savings compared to conventional gray infrastructure for stormwater management.^{See footnote 4} 

^{Credit: U.S. Environmental Protection Agency.}

Hard infrastructure, like roads, can exacerbate flooding challenges by reducing the surface area providing natural water storage capacity or by acting as barriers to the surface flow of water.^{See footnote 5} Additionally, many forms of infrastructure are designed for long lifespans, sometimes many decades for larger investments like bridges. It is therefore important to ensure that these investments will be justified, cost-effective, and informed by the latest data relating both to the need for the infrastructure, and potential risks like flooding.

Planning, appropriately, plays a key role in infrastructure decisionmaking, providing an opportunity to develop a long-term vision and establish priorities for investment needs over time. Infrastructure planning processes can be a useful way to ensure that nature-based solutions are integrated into the built environment and help to minimize environmental impacts like worsened runoff that might otherwise occur from hard infrastructure alone. By recognizing and taking advantage of opportunities upfront, especially during the initial planning phase, local governments can help ensure that benefits provided by nature-based resilience and flood mitigation are realized from infrastructure investments and projects long into the future.

This objective focuses on how parishes and municipalities in Region Seven can integrate policies promoting nature-based solutions into different infrastructure planning processes. For a more holistic approach, local governments should consider conducting infrastructure planning in conjunction with the approaches for fostering resilient, affordable housing (discussed in Goal Three and Goal Four) and for incorporating nature-based approaches and open space in neighborhoods (discussed in Objective 1.2).

How to Make Progress on This Objective

Three types of processes that lend themselves well to integrating nature-based solutions include:

• Transportation planning;
• Drainage and stormwater management planning; and 
• Other broader (non-infrastructure specific) processes, such as climate adaptation, resilience and hazard mitigation planning.
  

These plans can be used individually or together. However, overall, when developing new or amending existing plans, parishes and municipalities should make an effort to integrate nature-based projects into these plans to help ensure their benefits can be realized community-wide. 

Transportation Planning

“Transportation planning” often refers specifically to the development of long-range transportation plans, a prerequisite for states and urbanized regions to receive federal surface transportation funding. However, individual parishes and municipalities may wish to develop their own transportation plans to set priorities for local investment needs. Used in this part, “transportation planning” is intended to refer to local (parish or municipal) transportation planning, but these recommendations may also be applied in the context of statewide or metropolitan long-range transportation planning. Transportation planning should also integrate well with other forms of development-related planning, including comprehensive planning and any other plans that address land-use patterns and housing considerations.

There are many opportunities to integrate nature-based solutions into transportation planning and design. In doing so, it is possible to mitigate the flooding of roads and other infrastructure, while providing other social, environmental, and aesthetic benefits. Along roadways, for example, nature-based projects have proven to be effective at reducing air pollution including particulate matter, which can be particularly important in urban areas with more vehicular traffic.^{See footnote 6} These types of solutions can include tree planting, the installation of bioswales, the introduction of other green features along the right-of-way, and replacing traditional, non-permeable roads with permeable pavements (particularly for roads with low-volume traffic). Other nature-based solutions like vegetated berms have been also studied for the potential to provide protection for coastal roads from coastal flooding and surge.^{See footnote 7}

Local governments that opt to develop transportation plans, such as a  transportation master plan or transportation adaptation plan, can prioritize nature-based solutions in these documents as a way to steer investments towards these infrastructure projects that will help build resilience and mitigate flooding. For example, Ascension Parish developed a Transportation Master Plan in 2020 that identifies green infrastructure as a policy consideration that will help the parish achieve its overall vision.^{See footnote 8} The parish recommends using “green infrastructure best practices when possible for transportation improvements” and adopting green street standards “to provide additional benefits for stormwater management.”^{See footnote 9}

Drainage and Stormwater Management Planning

Another way that local governments can plan for nature-based flood mitigation is through drainage master planning or stormwater management planning. Drainage master plans and stormwater management plans provide an overall vision and plan for managing surface water and storm runoff, identifying drainage and flooding challenges and proposing infrastructure investments and regulatory changes to mitigate these challenges.

East Baton Rouge Parish is in the process of finalizing a comprehensive Stormwater Master Plan, which includes gathering data and developing models to understand buildings and areas at higher risk from flooding now and in the future. The parish is working to identify criteria, guidance, ordinances, projects, and other activities to mitigate flooding, and ultimately will develop a 20-year stormwater capital improvement plan to prioritize projects based on established criteria.^{See footnote 10} During the process of developing its Stormwater Master Plan, the parish also approved an interim change to its Unified Development Code to require the prioritization of green infrastructure solutions in transportation investments.^{See footnote 11}

On a smaller scale, many local governments require drainage plans as a condition of subdivision development, which can help mitigate any exacerbated flood impacts that would otherwise occur as a result of development activities. St. John the Baptist Parish mandates that project proponents create a stormwater management plan for any development occurring on one acre or more (or resulting in the installation of one acre or more of impervious surface).^{See footnote 12} This plan must “include post-development stormwater best management practices (BMPs) that limit the post-developed peak flow rate to the pre-developed peak flow rate for the ten-year, 24-hour and the 25-year, 24-hour storm event.”^{See footnote 13} St. Tammany Parish requires a drainage and pavement plan for “construction of commercial, industrial, institutional and certain multifamily developments, with the goal of improving pre-development runoff and reducing post-development runoff based on a minimum 25-year storm event.”^{See footnote 14}

Broader Cross-Sector Planning

Although not specific to infrastructure, local governments can also integrate policies and projects featuring nature-based solutions in other types of crosscutting plans, such as local comprehensive, hazard mitigation, and climate adaptation and resilience plans.

Comprehensive Planning

As discussed previously in Objective 1.1 and Objective 2.2, comprehensive planning provides the overarching policy vision for development within a specified parish or municipality. Comprehensive plans can therefore help a local government establish policies that prioritize green infrastructure and nature-based solutions in the built environment as land is developed or redeveloped.

Hazard Mitigation Planning

Hazard mitigation planning is another valuable tool for expanding the use of nature-based solutions, particularly in that it opens up new potential sources of funding to implement these projects. Developing a hazard mitigation plan (HMP) is a prerequisite for receiving Hazard Mitigation Assistance (HMA) from the Federal Emergency Management Agency (FEMA).^{See footnote 15} Projects implemented with HMA funds must align with priorities established and mitigate vulnerabilities identified in a local government’s HMP. Hazard mitigation planning can also earn a community credit under Community Rating System (CRS) Activity 510 ⎯ Floodplain Management Planning (although the maximum credit awarded is for the development of a community-wide floodplain management plan rather than a multi-hazard plan).^{See footnote 16}

Climate Adaptation and Resilience Planning

Climate adaptation and resilience plans outline or direct how local governments will aim to address forecasted climate change impacts, including challenges related to floods increasing in magnitude and frequency. These plans vary in format, level of detail, and sectors covered, among other factors, and are often preceded by and aligned with or include a climate vulnerability assessment. Adaptation and resilience plans are a logical vehicle for identifying priorities to reduce flood impacts, including through nature-based solutions; however, they typically lack the same authority or legal status of a local comprehensive plan or hazard mitigation plan.

Crosscutting Considerations and Practice Tips

When considering the most effective ways to integrate nature-based solutions in infrastructure-related planning processes, decisionmakers may find the following crosscutting considerations and practice tips useful:

• Engage communities throughout planning and implementation
• Lead with data 
• Educate the public and elected officials about the benefits of nature-based solutions
• Coordinate with other authorities within the parish
• Identify and allocate long-term funding for maintenance

These tips are based on priority implementation best practices and considerations most relevant to this specific objective and do not present an exhaustive list for regional and local planners and policymakers. In addition to this objective, decisionmakers should, at a minimum, also refer to Goal Five for crosscutting practice tips and considerations including structuring equitable and inclusive community engagement processes and using quantitative and qualitative data to inform decisions.

It is important to acknowledge that every jurisdiction will be starting from a different place and have a unique local context and needs, among other factors. Therefore, these practice tips could be adopted individually, collectively, or not at all. It will be up to policymakers to work directly with their communities and other key stakeholders and partners to assess and determine potential tools and approaches to implement this goal and objective.

• Engage communities throughout planning and implementation: Nature-based solutions can provide substantial benefits to communities in the form of flood mitigation, improved air quality, heat mitigation, aesthetic improvements, recreational opportunities, and general health and well-being. However, there are challenges with implementing these projects, particularly relating to upfront and maintenance costs, especially when considered outside of the context of long-term cost benefits or when not considering the advantages of co-benefits. Additionally, in areas at risk of gentrification, nature-based solutions have the potential to actually harm communities and exacerbate displacement pressures. Policymakers should practice meaningful engagement early and throughout infrastructure planning processes to ensure that policies and priorities included in these plans reflect the needs of communities. Effective community and stakeholder engagement practices that decisionmakers can adopt in this context are discussed further in Objective 5.1.
• Lead with data: As with other decisions regarding flood risk mitigation, planners and policymakers should ensure that planning efforts are informed by the latest data and science. This should include, as part of the planning process, a standardized method to integrate any updates to the science and analysis related to flood risk and the economic and environmental benefits of nature-based solutions. Accurate data and models with a good understanding of uncertainties can help local governments justify policy changes and projects prioritized in infrastructure planning efforts, as well as investment decisions. For more information on prioritizing data needs related to flood mitigation and green space, see Objective 5.2 and Objective 5.3.
• Educate the public and elected officials about the benefits of nature-based solutions: In order to build capacity and generate buy in from community members and organizations, academic and private experts, and elected officials to prioritize nature-based solutions, these audiences should have access to spaces where they can develop a common understanding of the many benefits of these approaches, including social, environmental, and economic co-benefits. Local governments should consider a variety of approaches to interact with relevant audiences, such as through fact sheets, social media, displays and signs in preservation areas, and through meetings and other forms of in-person and virtual engagement.
• Coordinate with other agencies and authorities within the parish: As with Objective 2.2 and Objective 2.3, intraparish coordination should also be prioritized in infrastructure planning processes. This is particularly important across agencies and departments like planning, transportation, and the environment because they may not often interact with one another and will need to coordinate to plan for and implement nature-based solutions as part of infrastructure investments. A clear understanding of the key agencies’ authorities is critical. Any relevant agencies that may need to be involved in the implementation of these projects should communicate regularly and have collaboration structures in place to ease project implementation.
• Identify and allocate long-term funding for maintenance: One of the main challenges of implementing nature-based solutions is in long-term financing and structures in place for maintenance, which is critical for these projects to function properly (i.e., for flood mitigation and other purposes). There are many options for funding and financing nature-based solutions, but local governments should understand the potential limitations (e.g., whether certain sources can be used for ongoing maintenance or only as capital investments). For more information on funding and financing nature-based solutions, see the Georgetown Climate Center’s Green Infrastructure Toolkit, Funding and Financing.

The summaries below highlight resources and case studies available in Georgetown Climate Center’s Adaptation Clearinghouse that are relevant to this objective. They illustrate how many of the above benefits, practice tips, and planning, legal, and policy tools were or are being evaluated and used in practice in different jurisdictions. To learn more and navigate to the Adaptation Clearinghouse, click on the “View Resource” buttons.