Abstract

The effects of aluminum sulfate (alum) treatment on water quality in 4 lakes of the Minneapolis Chain of Lakes (MN, USA) were examined. Lakes Harriet and Calhoun (treated in 2001) and Cedar Lake and Lake of the Isles (treated in 1996) all showed initial water quality improvement based on surface water total phosphorus (TP), chlorophyll a (Chl-a), and Secchi disk depth. Three lakes (Harriet, Calhoun, and Cedar) were at or below historical estimates of growing season average TP after treatment and showed continued improvement in surface water quality through 2005. Lake of the Isles, which received the lowest alum dose, returned to pretreatment conditions after 6 years. Estimates of sediment phosphorus (P) release rates, however, indicated that alum treatment still limited internal P release in all 4 lakes. Although the alum application to Lake Harriet was a littoral-only treatment, water quality improved in this lake as well. The aluminum hydroxide floc drifted to the deeper part of the lake, reducing internal P release from deeper sediments by 85% in the 2 years following treatment, leading to unexpected improvements in surface water Chl-a and TP concentrations.

Keywords

alum; aluminum sulfate; phosphorus; sediment; water quality

Published in

Lake and reservoir management
2011, Volume: 27, number: 3, pages: 220-228
Publisher: TAYLOR & FRANCIS INC

SLU Authors

• Huser, Brian

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

SDG6 Ensure availability and sustainable management of water and sanitation for all


UKÄ Subject classification

Fish and Aquacultural Science


Publication identifier

DOI: https://doi.org/10.1080/07438141.2011.601400

Permanent link to this page (URI)

https://res.slu.se/id/publ/57785