You’re at home cooking yourself some dinner. You fill your plate but before you sit down to eat you walk over to the garbage can and dump a quarter of your meal.

Insane? Well, that’s exactly what we’re doing with our drinking water.

In Ontario, some new numbers were released today and they’re staggering. A study by professors in the University of Toronto’s civil engineering department found that municipal water systems across Ontario have leakage rates of treated water ranging from 10 to 50 per cent, with the average conservatively estimated at 25 per cent. This, they estimate, translates into $700 million annually that taxpayers are paying for water that never reaches their taps.

“That’s some 327 million cubic meters of water lost each year — enough to fill about 131,000 Olympic-sized swimming pools,” according to the study, which was done in partnership with the Residential and Civil Construction Alliance of Ontario. Then there’s all the energy that’s used to treat and pump that lost water and the environmental consequences of having it leak into the ground, where sinkholes can form and basement can flood.

This isn’t the kind of thing consumers like to hear when they’re being asked to conserve water, install low-flush toilets, use rain barrels, and let their lawns and flowers go brown.

The study calls for large and immediate investments in rehabilitating water pipes. Problems tackled today in a significant manner will lead to more savings down the road. For example, the study calculates what Ontario could have saved had it made the necessary investments 10 years ago, rather than deferring maintenance. “The cumulative wasted energy due to deferring maintenance amounts to $161 million over the last 10 years. That is, had Ontario spent the same amount of money on maintenance of leaky pipes at one point (ten years ago) instead of distributing the same amount of money over 10 years, the savings in energy alone could have reached over $160 million.”

The pressing need to invest bodes well for companies such as Pressure Pipe Inspection Company in Mississauga, Ontario, which has developed better ways to detect underground leaks in municipal water infrastructure.