Figure 1. Typology of Stormwater Design Adaptations to Climate Change
Stormwater management systems have historically been designed based on the assumption that climate is stable. The unprecedented rate of change in global climate patterns therefore has important implications for stormwater managers; yet, incorporating climate information into stormwater management has been a challenge for many communities. This study’s objective was to review the existing state post-construction stormwater standards to provide a clearer understanding of the current stormwater management approaches to climate resiliency.
To achieve this objective, CWP first reviewed the technical literature to identify: 1) vulnerabilities posed by climate change to effective stormwater management and 2) best stormwater design practices to manage these vulnerabilities (Figure 1). Next, CWP evaluated state-published stormwater standards with respect to each state’s specific vulnerabilities and the degree to which stormwater-related climate adaptations have been incorporated into standards. The questionnaire also evaluated the extent to which the standards are up–to–date and based on the best available science and practices.
Next, CWP categorized each state based on its overall vulnerability to stormwater-related climate impacts, accounting for the extent to which major climate impacts are expected in each U.S. region and the projected increase in developed land over the next 25 years. CWP used the scores from the state stormwater standards review to characterize the overall readiness of each state to adapt their standards to the expected climate impacts. Finally, CWP compared state vulnerabilities to readiness (Figure 2) and identified recommendations for states to close the gaps.
This study focused on improving resilience to stormwater-related climate impacts through changes to post-construction stormwater standards at the state level. Future work on this topic by the National Watershed Research Network will drill down to the local level to identify innovative approaches being used by municipalities to increase the resilience of existing developed areas to stormwater-related climate impacts.
The white paper and associated products are available for download below.
Figure 2. State Vulnerability and Readiness Categorization
Download Individual White Paper Sections:
- Executive Summary
- White Paper Main Body
- Appendix A: Study Methods
- Appendix B: State Post-Construction Stormwater Standards Review Questionnaire and Scoring System
- Appendix C: State Profile Sheets
- Appendix D: State-Specific Recommendations
Download the Climate Assessment Tool for Stormwater Standards. Local or regional agencies can use this tool to evaluate their own stormwater standards.
Get the Data. State agencies can use the State Data Tool to look up their projected levels of climate vulnerability and readiness and access state-specific recommendations.
To learn more, contact Karen Cappiella (kc@cwp.org) or Deb Caraco (dsc@cwp.org).
