Non-Potable Water Systems
Non-potable water systems distribute water that is not designed for human consumption but are an efficient and environmentally friendly way to operate a wide range of appliances, including toilets and irrigation systems. However, it is imperative that this type of system is installed and inspected properly to avoid leaking, or worse, contamination of drinking water. As such, there are eight tests and visual inspections, specified in Sections 108, 312, and Sections 1302.12.1 through 1302.12.7 of the 2022 NYC Plumbing Code, that must be performed to ensure proper installation.
Collection pipe and vent:
Collection pipes and vents can be tested using water, air, or smoke, but must have no leaks and be tight at all points.
Storage tank:
Storage tanks must also be tested for leaks, but there are 3 specific parts of the storage tank that require close inspection. The overflow system must be verified to have no leaks and proper drainage, the tank drain must be observed for proper operation, and the makeup water system must be observed not only for proper operation but also for automatic shutoff of the system at the refill threshold.
Water supply system:
On top of all the previous leak tests, the entire system (or in some cases just the completed portion) must be pressure tested for leaks above its working pressure. This must be done using potable water.
Backflow prevention assemblies:
Errors or defects in backflow prevention assemblies pose some of the highest risk to public health, in that they can contaminate potable water systems. Because of this, all backflow prevention assemblies must be inspected and tested after installation or repairs and annually thereafter. This includes but is not limited to air gaps, spill-proof vacuum breakers, pressure vacuum breaker assemblies, and hose connection backflow preventers.
Vermin and insect protection:
As many non-potable water systems use air gaps and vents, proper measures must be taken to protect the system (and thus the buildings and people who use it) from insects and other vermin.
Water quality:
Though it is not necessary for every system, some non-potable water systems treat the water before it is used. When they do, the water quality must be tested and monitored to ensure safe use.
Cross connection control:
A lot of work goes into backflow prevention and inspection, but all of this becomes for nothing if the nonpotable water system is connected to a potable water system without the proper air gap. On top of this proper signage must be displayed to reduce the risk of future cross connections, and the pipes that carry non-potable water must be purple in color.
Roofwasher (if applicable):
Roofwashers must be tested by introducing water into the gutters to verify that enough rainwater is diverted in order to clear debris, that the amount of diverted water is field adjustable, and that diverted water is drained properly. On top of this, it must be verified that the roofwasher operates automatically and is accessible for maintenance and service.
Every system is unique and poses a unique set of challenges. No matter the type of non-potable water system, we at EPIC are always prepared to provide the diligent oversight and code-required inspections that these systems require.