Quantifying phosphorous loadings in the Thames River in Canada

Abstract

The Canada Ontario agreement requires reduction of total phosphorous (TP) loadings to prevent algae blooms in Lake Erie. This study was to consider TP loadings from the Thames River and potential methods needed to determine actual loadings. The study found TP loading in the Thames River was dominated by peak flow events and between 10 and 15% of the flow had over 60% of the loading. Identification of TP and Dissolved Reactive Phosphate (DRG) and/or Ortho phosphorous (Ortho P) have similar ratios with TP in the Thames River although are not the same in the main, north and south branches. Continuous ortho P monitoring equipment could be used to estimate TP loads based on ratios of Ortho P to TP established in the river shed. A description and cost estimate for a continuous monitoring system is included in the study. Reduction of TP loadings requires methods that can deal with the peak flows and one option could be wetlands along the river basin.