Evaluation of stream gauge density and implementing the concept of virtual gauges in northern Ontario for watershed modeling

Abstract

A balanced stream gauge network design is required to establish scientifically defensible baseline hydrological conditions in order to simulate their future responses to changes in climate and land use practices. The objectives of this study were twofold. The first objective was to evaluate Water Survey of Canada's HYDAT stream gauge density in Northern Ontario watersheds against World Meteorological Organisation (2008) guidelines. The second objective was to implement the concept of virtual gauges into the stream network. The virtual gauges represented are the discontinued gauges. Monthly mean streamflow was re-constructed for nine virtual gauges up to 2015, reducing the extent of data needs. The re-constructed data were tested using the coefficient of determination. Mean annual flow, annual and summer runoff coefficients, and derivatives of annual flow duration curves were used to describe the suitability of the data for watershed modeling. Our network design is cost efficient, suitable for the landscape and optimizes available hydrologic information to support the Government of Ontario's Far North Land Use Planning Initiative.