Achieving Water Conservation: Dilution Isn’t the Solution!

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To conserve and better manage their water use, more and more businesses are opting for closed water systems, where every drop of water taken is reused internally. Closing their water system to reduce water consumption as much as possible not only allows businesses to lower their operation costs, but more importantly, to decrease their environmental footprint. In many industries, such as pulp and paper, less heating is required, which translates into less non-renewable energy, and consequently, less greenhouse gases.

However, beneficial as this all sounds, closed water systems can pose an unintended, unanticipated challenge due to the fact that consuming less water can increase concentrations of substances in water to a point that companies fail toxicity testing.  And, as we know, toxicity regulations can carry salty penalties.

In 2004, Cascades was ordered to pay $138,000 in penalty for having failed Canada’s “rainbow trout test,” a sensitive toxicity analysis based on the survival of rainbow trout in undiluted effluents for a period of 96 hours.  Internal audits were unsuccessful at identifying the root cause of the problem, but testing results eventually came back to normal. One of our assumptions was that as long as you use a biological test with a living organism, there is a chance that you will get a false positive.  The other kicker for us was that if lots of wastewater had been discharged by our plant (which it wasn’t), we actually would have received a passing grade, simply due to the effect of dilution.

You see, toxicity methodologies were developed at a time when the majority of companies did not work on having an environmentally sound closed water system and it was a forgone conclusion that a large quantity of water was being discharged. For example, effluent flow by U.S. pulp and paper mills averaged about 150m3/ton in 1959, whereas the industry’s average annual water use has lowered to about 60m3/ton in the last few years.  By comparison, Cascades averaged 12.4m3/ton in 2010 when factoring all types of paper-based products.

Conserving more water has all kinds of benefits, such as reduced environmental impact (including greenhouse gases), biological oxygen demand (BOD) and quantity of suspended solids rejected in the effluent, but unfortunately, it also increases companies’ risks of not meeting regulated toxicity levels merely due to the greater concentration of effluents. Failing the toxicity tests has major business and reputational consequences, not the least of which is being perceived as polluting water streams. Important relationships built over years of close work with NGOs, consumers, municipalities, and governments towards environmental protection hang so much in the balance that some companies may simply restrain from working harder on water conservation. So what changes need to happen for businesses to focus even more on water conservation?

In looking for answers, the solution is not to do away with testing effluents or to use less stringent testing methods. Companies have to reduce their environmental impact by replacing chemicals with less damaging products and by getting the best available water treatment systems.

Abolishing or easing up the liabilities of toxicity isn’t the answer either.  Penalties are necessary and companies that pollute can’t get free passes.

The solution seems simple enough: have water used and discharged factor in the determination of toxicity levels. For example, if the toxicity is calculated with a normal effluent of 60m3/ton, a company that discharges half the quantity of water should be allowed to release twice the concentration of chemicals, which is equivalent in terms of loads to the river. We all know that the test itself does not represent what goes on in reality since fish don’t live in concentrated effluents. If water conservancy is the goal, then new and adapted regulations are warranted.

There are about 53,000 water agencies in the United States, so we can imagine that getting all of them and businesses to come together and develop a coherent point of view about water management isn’t going to happen all at once.  The challenge of water conservation will require that we balance out all of these needs and develop a global perspective.

With studies and facts on hand, it should be easier to focus on water conservation and better understand all the implications.  Participating in water working groups with NGOs, governments and businesses is one way of better understanding this multifaceted issue and work towards better regulations. Another way to create a partnership and better understand other stakeholders’ viewpoints is to work with other parties to conduct studies on the potential impact on ecosystems.  In my previous article on water conservation, it was established that businesses should perform water life cycle analysis to distinguish between wisdom and facts about water reduction. By precisely measuring environmental footprint and challenging each other, it will be clear that dilution isn’t the solution.

Elaine Tassoni, M.Sc., is the Communication and Sustainability Manager at Cascades Tissue Group’s head office. Cascades Tissue is the fourth largest manufacturer of tissue paper in North America. It sells the North River line of environmentally preferable towel and tissue products, which are entirely composed  of recycled paper,  mostly from post-consumer material, and are produced using Green-e certified wind energy and 80 percent less water than the North American paper industry average. Elaine can be reached at: elaine_tassoni@cascades.com or 450-444-6459.

Environment + Energy Leader