Our LEED v2.1 project is a 20,000 square foot nanotorium built as an addition to an existing community center. We wish to pursue WEc2 - Innovative Wastewater Technologies on this project and would like to know if our strategy for compliance is acceptable. On this project, use of a standard pool filtration system would produce 11,000 gallons of backwash water per week. Backwash water is run in reverse through pool filters for cleaning. Although backwash water is not used for sewage conveyance, local code requires that is discharged through the sanitary sewer line. On this project, we are installing an advanced filtration system which will reduce the volume of backwash water to 800 gallons per week. This will result in a weekly savings of 10,200 gallons of potable water (over 500,000 gallons of water per year). Along with additional water saving strategies that will be included on this project (waterless urinals, low-flow fixtures), the total volume of potable water being discharged to the sanitary sewer line will be reduced from a baseline of 20,000 gallons per week to 7,400 gallons - a reduction of 63%. We would like to know if we can include the pool backwash water savings in our calculations for WEc2 - Innovative Wastewater Technologies. We believe we are meeting the intent of the credit by significantly reducing the generation of wastewater and the potable water demand.
As noted under CIR ruling dated 3/9/2004, process water use is not eligible for consideration under WEc2 or WEc3. However, the optimization of process water use is eligible for LEED credit under the Innovation in Design category. Please see IDc1.1 CIR rulings dated 8/31/2004 and 5/13/2005 for guidance on attempting this as an innovation credit. Applicable Internationally.