Stormwater Drainage – Minnesota
Municipal Stormwater Vulnerability: Minneapolis & Victoria, MN
Abstract:
This study was the fourth in an ongoing program to investigate unresolved issues pertaining to stormwater adaptation. The overarching purpose of this program was to promote stakeholder-driven adaptation of vulnerable stormwater management systems and related water resources, by demonstrating, implementing, and disseminating a quantified, local-scale, and actionable protocol for maintaining historical risk levels in communities facing significant impacts from climate change. The project utilized an interdisciplinary team of investigators and stakeholders, to transfer coupled-climate model projections to the sub-watershed scale, in a form understandable to planners, resource managers and decision-makers. On a planning scale, the study sought to: Model capacities required for the existing infrastructure to convey peak flows from projected mid-21st century climate-changed precipitation and population growth; Model water quality impacts from projected mid-21st century climate-changed precipitation and population growth; Manage uncertainty in coupled-climate model output and associated downscaling; Provide a risk-based, prioritized schedule for adaptation of subcatchments and the stormwater management system; Estimate the cost of adapting the infrastructure to required capacities; Assess the potential for BMPs and Low Impact Development methods to provide more economical management of peak flows than drainage system upsizing. Through stakeholder participation, and community education and outreach efforts, the project provide a forum and participative decision-making process to empower communities to implement the adaptation plan.
Project activities included:
As necessary, limited fieldwork to validate existing hydrological and hydraulic models; Statistical downscaling of coupled-climate model output for a robust range of models and emissions scenarios; Development build-out to current zoning regulations, under standard and Low-Impact-Development methods; Model of required stormwater system capacity to accommodate climate change and population growth; Costs to upgrade the existing stormwater system, under replacement-cost, cost-avoidance, and substitution cost assumptions; Production of video, graphics, photographs, and a webcast to support communication of results; Implementation of a targeted program of community and stakeholder outreach, education, and participative decision-making; Dissemination of results through conference presentations and peer-reviewed publications.
These analyses and associated outreach program provided both new and synthesized science-based knowledge; identified impacts and societal vulnerability; and provided a practical template to support stakeholder-driven implementation of adaptation programs. This study made a significant contribution toward the generation of reliable and specific local-scale estimates of impacts from climate change, in support of programs to adapt civil infrastructures.
