It’s no secret that here at the Earth Rangers Centre (ERC) our goal is to reach an annual net-zero energy balance for the building – balancing our consumption of energy with on-site generation. However, green buildings do not focus solely on energy consumption, we look at water efficiency, integration into the local environment, indoor air quality and other factors. Thanks to a grant from the RBC Blue Water Project, we are undertaking a project that will highlight our water conservation strategies and demonstrate the value of these strategies.
The water cycle at the Earth Rangers Centre is not one seen in typical office buildings. The ERC is not supplied by a municipal water system, nor is it connected to a sewer or storm drains due to our location in the middle of the Kortright Centre for Conservation in Woodbridge, Ontario. All potable (drinking) water comes from an on-site well. Black water (raw sewage from toilets and urinals) as well as grey water (from all other drains like sinks, showers, kitchens etc.) is processed on-site by our wastewater treatment plant for re-use where possible. We can process up to 12,800 liters of black water per day.
Currently, six water meters track our consumption and re-use of water in the building. These meters have allowed us to attain LEED credits for sub-metering and monitoring of these systems. We can track hot water use, drinking water use, processed wastewater, consumed non-potable (for flushing toilets and urinals), and if any drinking water is needed in periods of drought to keep the firefighting reservoir at safe levels.
Even with this level of system detail, we still do not know – beyond an educated guess and industry rules of thumb – how much water we collect from the two flat roof surfaces. We also do not know how much water is used to maintain our various water filters, or how much non-potable water we use to irrigate our green roof. RBC’s grant will allow us to purchase, install and monitor data from four additional meters. These meters will track how much water we collect from our white roof, how much rain water drains from the green roof surface, how much we water the plants and the final meter will track the filter maintenance use.
Canadians use more fresh water, per capita, than any country in the world. This project will let us complete the entire picture of water use at the ERC, with our goal being to source as close to 100% of the site’s water supply from natural, closed loop water systems. We can then share the results and hopefully inspire others to improve their use of this precious resource.