What? Water samples are collected in Cape Breton Highlands National Park in various freshwater lakes and streams. When? Water samples are taken in select park lakes biannually (ie. spring and fall) and in select park streams annually (during fall season). How? Water samples are collected by hand in identified park waters and sent into Environment Canada for analysis of identified parameters. Why? Water quality is a globally accepted and widely used measure for assessing the condition of freshwater ecosystems and has a pivotal effect on the integrity of aquatic ecosystems. The physical and chemical characteristics of water have a strong influence on aquatic biota and freshwater system processes. Additionally, many of the primary stressors to freshwater processes (ie. acidification, eutrophication, deforestation) are reflected in changes to water quality. Changes in water quality may provide an early warning of environmental stress to aquatic ecosystems.