Grey Water Systems
When do you need a permit?
You need a permit in any state if you alter your buildings plumbing. The simplest system to build without a permit is from the laundry and have similar guidelines in all states. In California, this is the only system that can be built without a permit.
If you live in Texas or Arizona, no permit is required if the flow from your grey water system is less than 400 gallons per day. If you live in New Mexico no permit is required if the flow is less than 250 gallons per day.