Can I Use Rainwater for Drinking if I Live Off-Grid in Tennessee?

Harvesting and Storage

In Tennessee, it’s essential to harvest and store rainwater in a way that prevents contamination and ensures quality. A typical roof catchment area of 1,000 square feet can collect around 600 gallons of rainwater per inch of rainfall. For a 1-inch rainfall event in Tennessee, which can occur several times a year, you’ll need a 6,000-gallon storage tank to collect and store rainwater for household use.

Treatment and Filtration

To make rainwater safe for drinking, you’ll need to implement a treatment and filtration system. A multi-stage treatment process typically involves physical filtration, chemical disinfection, and ultraviolet (UV) light treatment. You can use a sediment filter with a pore size of 5-10 microns to remove particulate matter, followed by a chlorine or ozone treatment to disinfect the water. Finally, a UV light system with a wavelength of 254 nanometers can provide an additional layer of disinfection.

Local Building Codes and Regulations

In Tennessee, the Tennessee Department of Environment and Conservation (TDEC) regulates rainwater harvesting systems. According to TDEC, rainwater harvesting systems must be designed and installed to prevent contamination of the stored water and to meet local building codes. This typically involves using food-grade materials for the storage tank, ensuring proper roof catchment and gutter design, and implementing a treatment and filtration system to produce safe drinking water. Consult with local authorities and certified professionals to ensure compliance with local regulations.