Leaky Faucet by Maarten van Damme

Leaky Faucet by Maarten Van Damme CC BY 2.0 via Flickr

The Water-Energy Nexus

A lot of energy goes into treating and distributing municipal water, so if you want to conserve energy, you need to conserve water.

Acidic water and corroded pipes conspire to leak the equivalent of 2,888 Olympic-sized swimming pools worth of Cape Breton’s treated water into the ground every year before it reaches its intended customers – that’s a 40 per cent leakage rate.

Acidic water and corroded pipes conspire to leak the equivalent of 2,888 Olympic-sized swimming pools worth of Cape Breton’s treated water into the ground every year before it reaches its intended customers – that’s a 40 per cent leakage rate.

This lost water is also a massive waste of energy. Just about anything a municipality wants to do with its water – pump it, treat it or heat it – requires energy. This relationship is known as the water-energy nexus. Leaking water is, in a very real way, leaking energy, and such massive inefficiencies – right across the country – are the reason water is the new frontier of energy conservation.

In Ontario, water services represent 40 per cent of the province’s natural gas usage and 12 per cent of its electricity. Similar percentages prevail in the rest of the provinces, which means that any water conservation opportunity is also a significant energy conservation opportunity.

And there’s no lack of those opportunities. Inefficiencies abound in water delivery systems.

A recent report by Halifax’s Ecology Action Centre (EAC) takes a first look at the relationship between water consumption and energy use within Nova Scotia. It finds that the Municipality of Cape Breton uses 30.9 terajoules per year (equivalent to the energy needed to power 291 homes) in providing water services – and then 40 per cent of that energy is lost through water leakage. There’s no question the municipality could save money and energy by reducing leaks, but it’s hardly alone: the national average for water leakage among water utilities is 15 per cent.

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Part of the reason the leakage rate is so high is because water is generally just not tracked very well, so a leak in the municipal system can persist for weeks before being noticed. As of 2011, an average of only 58 per cent of Canadian households used water meters. One of the EAC report’s primary recommendations is for metering to be installed on more systems and more homes, just like an energy provider would do. Amherst, Nova Scotia, implemented water metering nearly 20 years ago, and saw a 25 per cent increase in water conservation within a year.

However, most homes, towns and municipalities don’t currently know enough about their water consumption.

“Our biggest finding was that there is very little data to work with regarding our water use,” says report author Jennifer West.

It’s impossible to understand and protect a resource that isn’t being properly monitored!
– Jennifer West

The same is true across the rest of Canada – industrial usage represents a major water blindspot. “Major sectors are using large volumes of water with no public record,” says Ben Parfitt, of the Canadian Center for Policy Alternatives. He points to BC’s water-intensive pulp and paper sector, where only one out of thirty producers is metering their water use. This leaves no possibility for real-time adjustments or public input.

Parfitt offers BC’s tree logging database as a model for resource data sharing. The system provides up-to-date information on every tree logged within the province. “If the Province can produce a database of that complexity, it’s inconceivable that it couldn’t do the same with water. We need to know what we’ve got, how we’re depleting it and how we’re replenishing it.”

“In the absence of that information, we run the risk of poor management.”

Poor management inevitably leads to wasted money and energy. Ontario’s existing water conservation programs save approximately 6,500,000 cubic metres of water each year. The POLIS Water Sustainability Project reports that, “Collectively, these municipal programs will save an estimated 15 million dollars in energy costs over the next 10 years for pumping and treatment alone.”

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If the potential for enormous financial savings is not sufficient incentive to buckle down on the water-energy nexus, climate change is presenting us with a host of problems we can’t solve without considering the possible ripple effects through the rest of the nexus. For example, water is needed to refine oil products and energy is needed to produce clean drinking water. A flood or a blackout affects both. In 2011, the World Economic Forum declared that “any strategy that focuses on one part of the water-food-energy nexus without considering its interconnections risks serious unintended consequences.”

In Amherst, residential water consumption has been sinking by one per cent per year ever since the initial 25 per cent meter-induced drop. Despite the improvement, the local distribution system still loses 207 Olympic swimming pools worth of water every year while using enough energy to power 57 homes.

There are still plenty of gains to be made.

Stu Campana is an international environmental consultant, with expertise in water, energy and waste management. He is the Water Team Leader with Ecology Ottawa, has a master’s in Environment and Resource Management and writes the A\J Renewable Energy blog. Follow him on Twitter: @StuCampana.