Improvements Proposed to Measure Great Lakes Health

Picture of Sally Cole-Misch
Sally Cole-Misch
December 12, 2016


great lakes health indicators
Credit: wp paarz

Do the Great Lakes provide safe, high quality drinking water? Can we swim and fish without health concerns? Are fish and other aquatic species thriving or declining? To answer these questions, scientists and governments need accurate measures, or indicators, that reflect the health of the Great Lakes.

Indicators to assess the state of the Great Lakes have been part of work by Canada and the United States since the mid-1990s, when the first State of the Lakes Ecosystem Conference was held. The indicators developed out of this initiative have been refined and expanded over time.

When the Great Lakes Water Quality Agreement was amended in 2012, it placed a priority on monitoring and assessment to evaluate progress in Great Lakes restoration programs. The IJC held expert workshops to consider and evaluate the proposed indicators of this progress, which resulted in a proposed 21 indicators with 51 measures, or ways to assess these indicators. These are divided into two categories – those that monitor factors that affect human health and those that focus on the health of the Great Lakes ecosystem – and reflect the Agreement’s nine objectives


The Great Lakes Water Quality Agreement’s nine general objectives. Credit: S. Cole-Misch
The Great Lakes Water Quality Agreement’s nine general objectives. Credit: S. Cole-Misch

The IJC’s Great Lakes Science Advisory Board Research Coordination Committee released its report, Future Improvements to Great Lakes Indicators, on Dec. 12 that summarizes its work to identify which of these IJC indicators and measures have data and at what level for reporting the health of the Great Lakes. Based on this information, the Committee recommended improvements in indicators used by the governments to report progress in meeting the Agreement’s objectives.

As of result of its research, the Committee concluded that future assessments of Great Lakes health would benefit from the governments’ use of additional indicators and expanded efforts to compile, quantify and manage those indicator data. Specifically, the Committee recommends:

  • Using source water for the human health sub-indicators to measure the health of the Great Lakes as a source of drinking water
  • Adding total phosphorus, dissolved reactive phosphorus, and nitrate-nitrogen concentrations as indicator measures for Great Lakes nearshore zones
  • Adding loadings of total phosphorus and dissolved reactive phosphorus from the major Great Lakes tributaries
  • Adding nearshore predators’ abundance and recruitment to better assess the health of food webs
  • Reporting on progress in Asian carp monitoring and prevention
  • Addressing data gaps for appropriate indicators that have only partial data or no data by establishing a long-term focused sampling program
  • Standardizing assessment methods and data sources used to increase consistency in assessing long-term trends and detecting changes in lake health status
  • Overhauling data management and sharing so that data used in past assessments of progress be collated in a centralized publicly accessible location.

By improving Great Lakes indicators, the Committee believes that Canada, the US and the IJC can more fully assess the status of Great Lakes health and progress to achieve the Agreement’s objectives. 

Picture of Sally Cole-Misch
Sally Cole-Misch

Sally Cole-Misch is the public affairs officer for the IJC’s Great Lakes Regional Office.