Rating System

LEED BD+C: New Construction, LEED O+M: Existing Buildings, LEED BD+C: Core and Shell, LEED BD+C: Schools

Rating System Version

v3 - LEED 2009, v3 - LEED 2008, v2 - Schools 2007, v2 - LEED 2.2

Inquiry

The mechanical systems for this project are geothermal in design. Non-domestic use well water is supplied via a closed loop to an isolated heat pump heat exchanger to provide climate control of the building. The uncontaminated well water is then returned to the ground via a separate well, at a location different from where it was extracted. We would like to use a portion of this discharge well water for site irrigation. Our question is; will this water be considered a non-potable source to help achieve WE Credit 1.2? Our opinion is that this returned well water should be considered non-potable since its use in the irrigation system is secondary to the use of the geothermal system. Also, in using this water in the irrigation system, it is being applied to the landscape and provides a positive impact on the ground water table in the fact that it will replace soil moisture that would have been evaporated from the soil surface and therefore diminishing the moisture levels deeper within the soil profile. A certain portion of this water will also migrate through the soil profile back into the water table.