If you have a heavy leak in your toilet, it's easy to diagnose—the faint sound of the toilet tank constantly replenishing is a dead give away. What about a slow leak? Diagnose it with food coloring.

Fredericton has declared war on leaky toilets — which can waste up to a few hundred litres of water per day. Kathy Edwards is with the city's Water and Sewer department, and she's running the campaign ...