ALGAL BLOOMS IN THE GREAT LAKES OF NORTH AMERICA

 

POTENTIAL ADAPTATION MEASURES

Lessons learnt

With the current climate conditions, “there is no silver bullet” solution in reducing the magnitude and intensity of harmful algal blooms. Past and current multi-modeling projects at the watershed scale reduce the uncertainty of impact models and point to the right practices of reducing nutrients and sediments that feed the algal blooms. We have experienced that a multi-sectoral and interdisciplinary collaboration will lead to a science-based viable solutions and consensus in reducing the algal blooms. Lastly, we learned that stakeholder consultations and inputs are necessary in impact modeling projects.

Importance and relevance of adaptation

Current management practices and load reduction efforts do not account for the effects of climate change and the export reduction effectiveness of these practices in future climate is unknown. Adaptation includes identifying and implementing practices that would reduce nutrient and sediment loading (hence, algal blooms) despite the changing climate. Thus, climate adaptation would direct current resources and efforts to reduce efficiently future algal bloom occurrence.

Pros and cons or cost-benefit analysis of climate adaptation

There have been tremendous economic losses due to algal blooms in Lake Erie. The defining moment was when regulators banned Toledo’s tap for drinking and cooking for two days in early August 2014 when the water was found contaminated with toxins from Microcystis cyanobacteria bloom.  It cannot be emphasized enough that the risks of such drastic conditions to occur increases without climate adaption.  Researchers have started to analyze the benefits and cost of implementing management practices but without considering the effects of climate change and mostly at the agricultural farm level.  We advocate an integrated cost-benefit analyses that would encompass the costs, profit margins, and environmental outputs from all sectors (e.g. farmers, fishermen, boaters, resorts, etc.) in the western basin of Lake Erie and its watershed.

Policy aspects 

There is a consensus among academics, stakeholders, federal, state, and local agencies that the recurrence of algal blooms is mainly attributed to the increase in dissolved reactive phosphorus (DRP) loads to Lake Erie.  The annex 4 of the Great Lakes Water Quality Agreement (GLWQA) between the USA and Canada calls for a 40% reduction of phosphorus loads from the 2008 level. Domestic action plans are currently being developed at the federal and state levels to reduce phosphorus exports to Lake Erie. The information derived from this contract would certainly help in the adaptive management approach in phosphorus reduction and of the algal bloom problem in general.