CUERE Seminar Series - Dr. Bernice Rosenzweig

Dense, sewer-dependent cities are particularly vulnerable to cloudburst (short-duration, intense) rain events. These events overwhelm conventionally designed gray and green stormwater infrastructure and can result in life-threatening flash flooding and disruption of transportation and other critical systems. The short time scales associated with cloudbursts present unique challenges for forecasting, warning and monitoring, and their impacts remain poorly studied and are underrepresented in conventional flood risk assessment. These challenges were exemplified during 3 flood-generating cloudburst events that occurred in New York City this summer (2021), including the September 1, 2021 event associated with the remnants of Hurricane Ida that resulted in widespread, 1-hour rainfall accumulations in excess of those associated with a 100-year return interval. The risk associated with cloudburst events is projected to increase globally with climate change, but adaptation will be challenged by limitations in space and reliance on sub-grade infrastructure in cities like New York. In light of these constraints, it will be necessary to develop novel management strategies designed for the unique hydrography of dense urban watersheds.