Climate Change Threats to Stormwater Programs and Future Planning 

   Reported by Steve Peene, Geosyntec Consultants


What are the critical threats that you are facing relative to climate change? When asked this question, stormwater programs across the Southeast provided answers in two forms. The first related to what aspect of climate change (flooding, rainfall, heat) was most important and the second focused on local government’s ability to respond.

SWGridIn relation to the first, flooding was by far the most significant threat identified. Coastal communities were identified for specific concern because “they have the dual impact of sea level rise and likely significant increases in the magnitude of rare rain events and storm surge. To further complicate matters, coastal communities are often among the most densely populated and were often the first developed (i.e., they have the oldest infrastructure).” Issues that are linked to flooding were also identified including changing rainfall patterns, rising groundwater (reduced storage), and the need to update “design standards based on updated rainfall statistics. We are constructing stormwater infrastructure that will soon not have enough capacity for service levels expected”.

In relation to the second type of answer, aging infrastructure, funding, and the will to act were the top responses. The concern is how to plan for the future when we can’t even deal with the aging and undersized infrastructure we have now. One response summed up these issues - “In terms of climate change, funding is not yet at a level that can support the needs of local governments – we don’t even know what we need yet in terms of funding because we haven’t even really stared climate change in the eyes and assessed it meaningfully in most communities. Public discourse, misinformation, and distrust of science is also a serious hurdle since addressing climate threats is so time sensitive and some local governments cannot even discuss the issue yet.”

What is a reasonable time frame for future planning? Stormwater managers across the Southeast answer this question with some consistency with the most prevalent range on the order of 20 to 25 years as it relates to Capital Improvement Plan (CIP) plannings. Some responses identified that the time frame may vary between communities, and they will need to have differing time frames depending upon the types of infrastructure. This could lead to a “tiered” approach that looks at immediate problems (5-year), mid-level (20-year CIP), and more long term (50 years). Grant requirements and how they can dictate how far into the future programs need to plan was raised as a driver. Finally, some communities have not yet embraced the need for future planning and therefore they have not identified any future time frames, they’re “too busy dealing with the present issues and limited funding.”