They Go High, We Pump Low: Can the Diel Vertical Migration of HABs Protect Drinking Water Sources?

Session: 41a. - Great Lakes Harmful Algal Blooms Research from Watershed Influence to Ecosystem Effects

Eva Kramer, University of Toledo, [email protected]
Thomas Bridgeman, Dept. of Environmental Sciences, University of Toledo, [email protected]

Abstract

The increasing severity of Harmful Algal Blooms (HABs) in the Western Basin of Lake Erie necessitates investigation into new methods for protecting vital drinking water sources. The dominant HAB species in Western Lake Erie, Microcystis aeruginosa, has been shown to change its position in the water column according to time of day and wind mixing. The city of Toledo’s drinking water intake is located in near the lake bottom, therefore it may be possible to reduce intake exposure to Microcystis by increasing pumping rates when Microcystis is concentrated at the lake surface. This would lower the concentrations of algal toxins that enter the water plant, protecting important drinking water resources and reducing treatment costs. Five 24-hour sampling events were conducted near the city of Toledo’s drinking water intake during the bloom season in 2016 and 2017 to observe the vertical distribution and movement of HABs, associated toxins, and other algal species. We present the findings of these studies and discuss their implications for drinking water treatment.

1. Keyword
harmful algal blooms

2. Keyword
Lake Erie

3. Keyword
Microcystis

4. Additional Keyword
drinking water