Busting myths on water reuse
Guest Author - CAGBC’s Sites-Water TAG chair: Adam Stoker, P.Eng., LEED AP (BD+C, O+M, ND), Sustainable Infrastructure Engineer, The City of Calgary. on February 9, 2022
While water reuse was officially added to the National Plumbing Code in the 2015 edition, many water reuse systems don’t make it past concept design due to perceived regulatory barriers and a lack of clarity on applicable codes. The relevant section of the code is relatively brief and references CSA Standard CAN/CSA-B128.1 – Design and Installation of Non-Potable Water System – which not all project teams may be familiar with. So where do we start?
While some of the specifics will vary across the country, every project should start the process with a discussion with the safety codes officers in the authority having jurisdiction. In discussions with the safety
codes officers in my region (City of Calgary), I confirmed that rainwater and greywater reuse for flushing toilets, sub-surface irrigation, and other specialized applications (e.g., automated car washes) has been implemented successfully numerous times in the City. There is an established process for permitting these applications and internal experts are happy to point project teams to the appropriate codes, standards, and other guiding documents. In this region, as an example, safety codes officers will note the following information bulletins and guidelines to support project teams:
- Alberta Plumbing Safety – Information Bulletin – Reclaimed Water Systems
- Alberta – Public Health Guidelines for Water Reuse and Stormwater Use
- Alberta – Alternative Solutions Guide for Small System Water Reuse and Stormwater Use
While water reuse represents a new frontier to many in plumbing system design, it does not follow that permitting processes will be inherently complex or obfuscated. While not all water reuse systems will have straightforward permitting process (e.g., black water reuse would fall outside of what is covered above), many options are relatively accessible and your authority having jurisdiction can point you in the right direction.
Lastly, we recommend that project teams that are spending the time to engage with their local water and wastewater authorities to develop safe and effective water reuse systems check out the recently released LEED Pilot Credit: Integrated Project Water Reuse Strategy. This credit rewards those that seek to ensure building water reuse systems are regionally optimized, address local site conditions and water-related site regulations, and further community and regional water management priorities and objectives.