Urban flooding is a major challenge that is expected to get worse due to urbanization and climate change. Many cities recognize the potential of nature-based solutions (NbS) to manage and mitigate flooding, yet most lack systematic strategies for transitioning away from their existing conventional drainage systems. This paper is intended to provide natural resource managers, planners, and engineers with a step-wise approach to aid the strategic planning process for NbS. The strategic approach includes: map and restore/protect open spaces and natural pathways for water, evaluate NbS scenarios, select preferred combination of NbS, and determine transition pathways from existing conventional drainage systems to NbS. First, a GIS-based mapping is used to setup hydrology, map green infrastructure and identify potential areas for protection and restoration, fit a development/ redevelopment project to the site, and identify potential areas for NbS, factoring in site conditions and existing drainage systems. Second, NbS scenario analysis is applied to quantifying volume and pollutant load reduction while exploring the use of different NbS. A final step is applied to select the preferred combination of existing stormwater systems and NbS options, given site constraints, water quality/quantity reduction objectives, and key secondary social and ecological benefits (e.g. aesthetics, air quality, heat-island etc.). When used in combination, the strategic approach identifies a prioritized, optimal transition pathway from existing conventional drainage systems to NbS. The strategic approach is applied to urban watershed in Tampa, Florida.
