Modeling the Efficacy of Phosphorus Treatment Options for the Control of Cladophora in Lake Ontario

Session: 31. - Evaluation of the Current State of Ecological Modeling and Future Perspectives

Martin Auer, Dept. of Civil Engineering, Michigan Techn. University, mtauer@mtu.edu
Cory McDonald, Michigan Tech. Univ., Dept. of Civil & Env. Eng., cpmcdona@mtu.edu
Mark Rowe, Cooperative Institute for Great Lakes Research, mdrowe@umich.edu
Anika Kuczynski, National Institute of Water and Atmospheric Research, anika.kuczynski@niwa.co.nz
Pengfei Xue, Michigan Tech, pexue@mtu.edu
Ankita Bakshi, Michigan Technological University, abakshi@mtu.edu
Chenfu Huang, Michigan Technological University, chenfuh@mtu.edu

Abstract

Increases in water clarity in Lake Ontario, mediated by dreissenid filtration, have resulted in an insurgence in the growth of the attached, filamentous green alga Cladophora.  Nuisance levels of Cladophora growth are now experienced in urban areas on Lake Ontario receiving point source inputs of phosphorus.  Annex 4 of the Great Lakes Water Quality Protocol of 2012 calls for the development of phosphorus load reduction targets for watersheds with significant localized impacts.  Here, a secondary and tertiary phosphorus removal technologies considered for implementation of the Duffin Creek WPCP (Ajax-Pickering, ON) are examined for their efficacy in reducing levels of Cladophora growth.  The Great Lakes Cladophora model is applied in establishing a substance objective for phosphorus relative to Cladophora and FVCOM-GEM is used to simulate phosphorus levels in the Lake Ontario nearshore.  Of particular interest here is the interplay of hydrodynamic and biokinetic processes in establish the dimensions of the WPCP wastefield and thus the level of treatment required to achieve relief from nuisance conditions.

1. Keyword
Cladophora

2. Keyword
phosphorus

3. Keyword
modeling

4. Additional Keyword
Lake Ontario