Design and installation of aeration systems for hydropower, water supply reservoirs and other applications
Vadnais Lake, Minnesota
Vadnais Lake is located in Ramsey County, Minnesota
Consisting of an East Side and a West Side, with Sucker Lake Road dividing the lake
Vadnais Lake Hypolimnetic Oxygenation System
Saint Paul Regional Water Service
First Year Operation Results Mobley Engineering, Inc. Data Review Mark Mobley 02/15/2013
Operation of the hypolimnetic oxygen system (HOS) in Vadnais Lake during 2012 has resulted in dramatically increased dissolved oxygen (DO) levels in the reservoir and over the sediments. August DO levels in 2010 and 2011 were less than 2 mg/L in the hyolimnion, and 0 to 1 mg/L at the sediments. With operation of the HOS in 2012, the hypolimnion was maintained with DO levels over 7 mg/L and 1 to 3 mg/L at the sediments.
Iron (Fe) and manganese (Mn) concentrations were reduced or eliminated with operation of the oxygenation system. Summertime Fe concentrations spiked over 0.7 mg/L in 2010 and 0.4 mg/L in 2011. During 2012 the Fe concentrations were maintained at less than 0.1 mg/L until reservoir turnover. Manganese was reduced from spikes of 1.0 to 2.5 mg/L to less than 0.3 mg/L in 2012.
Aligning the diffuser to the area where the manifold will be installed
Hanging weights, Lake Vadnais, MN
Early morning, Lake Vadnais, MN
The LOX site
Mounds of algae were cleaned off of the lines prior to sinking
Mobley Engineering, Inc. • PO Box 600 Norris, Tennessee 37828 phone (865) 494-0600 • fax (865) 494-0611