Best Practices

Be sure you’ve included startup of a wastewater treatment system in contract documents and scope of services. You may want the commissioning agent to look at the wastewater treatment system too.

Consider including signage for water reduction strategies that may require special instructions for use. These may include: occupant signage for operating dual-flush toilets, waterless urinals and composting toilets, and for indicating non-potable water—and operational signage for distinguishing the pipes that carry reused water. Purple piping is commonly used for reclaimed water and, more recently, for recycled graywater.

If you will be using graywater, rainwater, or treated wastewater, you’ll need dual plumbing for interior water fixtures. Communicate this need to your civil and plumbing engineers. You should also discuss any location and structural issues if your project is going to have a rainwater cistern—sometimes they take up more space than anticipated.

Untreated rainwater and graywater may corrode plumbing systems or lead to biological growth. You should plan for water treatment and filtration, or use corrosion-resistant materials. All graywater plumbing and storage must be separate from regular sewage plumbing.

Review your water balance study and determine what water reuse would be most appropriate for your project.

Review your water balance study and determine what water reuse would be most appropriate for your project.

Remember that this credit is based on EPAct 1992 and subsequent rulings of EPAct 2005, the 2006 Uniform Plumbing Code, and the International Plumbing Code. The baseline case for this credit includes these standards:

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.

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.