Consider the different maintenance requirements for waterless fixtures. Waterless urinals and composting toilets require a different maintenance program from conventional fixtures.

Select water-efficient flush fixtures and determine the percentage of reduction from fixtures alone. 

Option 1: Reduce Potable Water Use for Building Sewage Conveyance by 50%

Consider installing permanent water metering for ongoing monitoring of the project’s water use. A submetering system can help operations staff detect problems early and facilitate future LEED-EBOM certification. 

Consider monitoring wastewater reduction in conjunction with EAc5: Measurement and Verification.

Well and pond water are not considered non-potable water for the purposes of this credit and must count as potable water—so you won’t get credit for substituting them for conventional water sources. Water types that do count as non-potable are: graywater (lavatory, sink, and shower water), rainwater, treated wastewater, air-conditioner condensate, reverse-osmosis reject, and sump-pump water. 

Begin developing your strategy for wastewater use reduction based on the option you’ve selected. Research low-flush fixtures, water reuse, and onsite treatment. 

Reducing your shower or sink flow rate will not help with credit compliance for WEc2 but, will help with WEp1 and WEc3. However, if your project is earning this credit through treating wastewater onsite, it is best to reduce the total quantity of water being treated. Therefore, a reduction in flow fixtures will minimize the total water needing treatment. 

When using the LEED Online credit forms, you need to complete the WEp1: Water Use Reduction—20% Reduction credit form first. Doing so automatically generates your baseline-case usage in WEc2. (See WEp1 for details on determining occupancy, usage, and FTE.) 

Determine your project’s baseline case wastewater generation. This will help you develop your strategy for reduction.