Conservation Training

Lake Water Level Management Under Climate Change

March 8, 2023

3:00 pm – 4:00 pm
Location: Online

Winter water level drawdown (WD) is a common lake management strategy to protect shorelines from ice damage, control nuisance macrophytes, and support recreation. Most WD lakes undergo small magnitude (<1 m) drawdowns without a special permit; thus, there is no database for where, when, and how lakes are drawn down. Moreover, there is little guidance (or adherence to any official guidelines) on drawdown depth and timing to meet management objectives while allowing refill to minimize ecological and recreational impacts. We developed novel methods that use satellite-derived lake surface area and water level to assess the prevalence and hydrologic characteristics (timing, magnitude, duration) of lakes that undergo WDs. A web interface, powered by Google Earth Engine, was developed to facilitate water level information access for stakeholders. We also developed a hydrologic modeling framework to evaluate the ability of lakes to meet different drawdown magnitudes and refill initiation timing, given different drawdown magnitudes and climate conditions. Unsurprisingly, there is high variability in potential to refill among lakes and years, and thus management strategies to optimize duration of the drawdown will be lake-specific. We will continue working with regional partners to disseminate information in order to help managers make climate-informed decisions.