My companion and I are beginning to homestead on forty acres in rural western North Carolina. We have decided to use water from natural springs on our property for our household needs, including drinking water. My question concerns the plastic holding tank that the water would be stored in before it enters our home. I’ve read that plastic leaches chemicals into the water and was wondering if you could advise us of a good filtering system that would protect us (as much as anyone can be totally protected from chemicals in this day and age!).
—DEBORAH SONG, VIA E-MAIL
Pliny Fisk and Gail Vittori reply:
Spring water can be an excellent water source, and the system you install will help ensure that you have safe, healthy water for all your household uses. First, verify the water’s quality, as contamination of water that appears to be “clean” can go undetected without thorough testing. A local health department or a do-it-yourself kit can provide this information. And, because spring water can be affected by remote sources that are in the springs’ recharge area but may be out of your sight, periodic testing is advised.
Your system’s design of piping, storage, and filtration should reflect your water quality concerns, as each of these components are potential points of contamination. For piping, we recommend polyethylene, a stable polymer that is unlikely to leach chemicals as can occur with polyvinyl chloride. For the storage tank, the water must be kept cool and free from direct sunlight, or the growth of algae and certain bacteria can become problematic. Polyethylene tanks (black) and galvanized metal tanks with an FDA-approved liner are preferred. For filtration, we advise a 0.5 micron filter to remove particulates and, for potable water, ultraviolet (UV) light sterilization.
Design your plumbing so the UV filter treats only the water used for potable purposes; there’s no need to purify the water in the toilet unless it’s a source of drinking water for your pets. This will lengthen the life of the UV system. For long-term water security, you may want to consider installing a rainwater harvesting system to supplement the spring water, with both water sources feeding into the same storage tank.
Periodic maintenance and testing of the system is essential. Eliminating sources of potential contamination throughout the system and from the life cycle of the materials used is the best way to ensure high-quality water.
Pliny Fisk and Gail Vittori are the co-directors of the Center for Maximum Potential Building Systems, a green building think tank in Austin, Texas. They are working with the Department of Energy’s Building America program and with the Environmental Protection Agency to develop software that helps builders and homeowners determine the impacts of the building materials they choose. Pliny and Gail are at the cutting edge of adaptable design and understanding our human footprint. “Ideally, a lot of what we’re trying to do is make the invisible visible,” Pliny says. “Because it’s not that we’re bad people; we just don’t understand the full impact of our choices.” Adds Gail, “You as a purchaser, builder, or designer have opportunities to make a big difference.”