A Multi-Tiered Approach to Managing a Complex Multi-Stakeholder System

The Qu’Appelle valley and its series of lakes are a unique feature on the Saskatchewan landscape.  The valley is on average 180 m deep, 2 km across and stretches 430 km from Lake Diefenbaker in Saskatchewan to the Assiniboine River in  Manitoba.  The eutrophic waterbodies within the Qu’Appelle valley contain the greatest diversity of fishes within Saskatchewan including the endangered bigmouth buffalo (Ictiobus cyprinellus).  Historically the Qu’Appelle was a semi-ephemeral environment feed by local run-off and spring flood waters from the South Saskatchewan River.  In the late 1960’s the construction of a series of dams on the Qu’Appelle resulted in increased annual flows and a highly managed system.  The Saskatchewan Water Security Agency is currently using and developing several tools for improved management of the Qu’Appelle system.  Here we present the use of Indicators of Hydraulic Alteration to compare past and present flows, the development of an Environmental Instream Flow Tool to gauge fish habitat needs and  development of a Bayesian Network model which can be used by water managers to understand the implications of various flows.  This multi-tiered approach will ensure a scientifically defensible management strategy is used to ensure this unique environment thrives while meeting numerous demands.