C. Kushnir

Evaluation of lead dissolution in drinking water distribution systems based on chemical thermodynamic constraints

Lead in drinking water is a major public health concern. Even extremely low lead levels in drinking water can impair cognitive and bodily functions. Lead-bearing plumbing materials and subsequent high lead concentrations in drinking water is a major issue in cities globally, including many Canadian cities. Municipalities still have water distribution systems with lead-bearing plumbing materials, most often present as connections between water mains and buildings (service lines). As a distribution system ages, a corrosion layer (or corrosion scale) forms on the interior of the service line. The release of lead from these corrosion scales represents the primary source of lead in drinking water. As per the 2013 annual report on drinking water in Ontario, 20 Ontario municipalities have been required to implement corrosion control strategies to reduce lead concentrations in drinking water. To design effective corrosion control strategies, there is a need to predict a priori the effect water chemistry adjustments will have on corrosion scale stability and thus lead concentrations. While thermodynamic models have been developed to understand lead corrosion chemistry, they are limited due to uncertainty in thermodynamic constants and solid phases included in the model. To develop a reliable and valuable modeling tool for drinking water utility operators and municipalities key knowledge gaps need to be addressed. These include reducing uncertainties in model parameters (ie., equilibrium constants) and understanding the effect of temperature on corrosion scale stability.

Addressing these knowledge gaps will provide a more reliable modeling tool that can be used by drinking water utilities to evaluate the effects of proposed water chemistry changes on corrosion scale prior to implementation.

Personal Background

I completed my undergraduate degree at the University of Guelph in Environmental Engineering. Subsequently I moved into the consulting sector in Oil and Gas in Western Canada. I decided to return to school at the University of Western for my M.Eng. During my initial semester, I decided to pursue an MSc. under Dr. Clare Robinson. Since then, I’ve graduated with my Masters and have stayed on to complete my PhD.

Awards


  • Ontario Graduate Scholarship, 2016 [Ongoing]
  • William E. and Ruth Lardner Graduate Award, University of Western, 2014
  • John Booker Award, University of Western, 2013
  • Helen Grace Tucker Award, University of Guelph, 2008