Description

1) Using Nature Based Solutions to Improve Transportation System Resiliency
Hunter Freeman, PE, McAdams, freeman@mcadamsco.com
Co-presenters: Andrew McDaniel, ahmcdaniel@ncdot.gov; Lauren Kolodij, laurenk@nccoast.org

Abstract: Released in March, 2021, The North Carolina Coastal Federation with support from the Pew Charitable Trusts, released a statewide Action Plan for Nature-based Stormwater Strategies in North Carolina. The Plan was developed with input from over 60 work group members representing North Carolina state and local government agencies, businesses, universities, landscape architects, engineers, non-profits and other sectors. Nature Based Stormwater Strategies work with the landscape to aid in reducing flood related risks to the while adding ecosystem value and biodiversity. These sustainable planning, design, environmental management, and engineering practices weave natural features into the built environment resulting in more resilient communities. NCDOT played an important role in the development of the plan, particularly the transportation chapter. As the owner & operator of over 80,000 miles of roadway from the mountains to the coast, NCDOT relies on a wide array of nature based strategies to mitigate risks from rainfall, floodwaters, and other climate related events. Floodplain management for transportation systems is more than just mapping and modeling, it’s a key component in every design and in the operation of our roadway network. Nature based stormwater strategies take on many forms of implementation, each of which have a direct connection to floodplain management. This presentation will offer ideas on how nature based solutions and strategies can be incorporated into the planning, design, construction, maintenance, and operation of linear transportation systems in ways that assist in reducing the risks posed by floodwaters. The presentation will include case studies from NCDOT and others on how transportation systems reduced their impact on flood prone areas as well as how transportation systems use nature based strategies to protect themselves from natural hazards.

2) Climate Adaptation - Integrating Solutions into a Coastal Community for the Future
John Millspaugh, PE, PMP, Arcadis, john.millspaugh@arcadis.com
Co-presenters: None

Abstract: The City of Norfolk was awarded a $115 million grant from the Department of Housing and Urban Development to address flooding due to storm surge and high rainfall in the Ohio Creek watershed. The design approach included an integrated stormwater management system within a shoreline defense system. Moreover, the water-management activities were designed to improve the neighborhood by increasing neighborhood connectivity, adding new and improved natural habitat, and increasing resilience to future flooding. The constructed project, anticipated to be complete early 2023 will include 10,000 linear feet of berms and coastal protection to protect the community up to the 100-year coastal surge event with climate change considerations. Green infrastructure (bioretention and permeable pavement) and nature based solutions (living shoreline) played an important role in conveyance pump station sizing, meeting water quality requirements, and creating a resilient sustainable solution of alleviating flooding in one of Norfolk’s oldest waterfront communities. The interior drainage system improvements will include replacement of existing grey infrastructure with 17,000 linear feet of new storm lines and two new stormwater pump stations for a greater capacity to meet the 10-yr 24 hr storm with climate change considerations. This presentation will focus on the implemented stormwater management system including green infrastructure, conveyance, and pump stations. A focus on incorporating the features within the project and residential constraints will be provided offering good practices and lessons learned for communities to consider in becoming more resilient into the future.

3) Alternative Procurement Strategies to Accelerate the Implementation of Green Infrastructure
Patrick Bradley, RES, LLC, pbradley@res.us
Co-presenters: None

Abstract: This presentation will outline innovative procurement methods and provide examples of where they’re already being successfully implemented, with the aim of supporting and inspiring other communities to benefit from these opportunities. An increased frequency of high-intensity, high-volume storms has contributed to gaps in stormwater management practices relative to local rules and regulations. Given this, communities across the Midwest are re-evaluating how to adequately address changing precipitation trends in the region. If such a gap in stormwater management has been realized for your community, then what is the ‘right’ way to resolve the matter? Increased stormwater detention and conveyance capacity are standard-bearer solutions. However, space is often a limiting factor for these stormwater solutions. If this is true for you, then perhaps green infrastructure solutions may help your community advance their stormwater management needs. Moreover, is the traditional design-bid-build the only way to secure a better system, funded completely upfront by the community? Does the responsibility and challenges of implementation sit solely with the community to figure out? Alternative methods for procurement exist that can be transformative to advancing the construction and installation of stormwater solutions, many of which work particularly well with green infrastructure projects. These include open call programs (e.g. St. Louis MSD); stormwater volume trading (StormStore in Chicago through MWRD); and stormwater utility district fees & associated reimbursement grants (e.g. Philadelphia). Along with these different procurement structures, municipalities can shift upfront funding responsibilities to private developers who agree to identify, secure land agreements, develop preliminary design—all at their own risk—in exchange for the ability to recoup that cost through funding on the back end from the municipality. State revolving loan funds or federal infrastructure dollars may also offer a source of reimbursement for communities for stormwater management and flood resiliency projects.