Instructions for Chlorination of private water supplies

Spring Reservoir

1. Drain reservoir, if using a spring. (If reservoir has a pump inside, do NOT drain it completely.) Wash walls and bottom of reservoir. Use pure bleach and a stiff brush.
2. Refill reservoir.
3. Pour one pint of bleach per 100 gallons of water into the reservoir. Mix the bleach into the water. Turn on each faucet in the house one at a time until you can smell the bleach, then turn off the faucets. Let bleach stay in the pipes for a minimum of 12 hours.
4. After 12 hours have passed, drain and refill reservoir. Turn on an outside faucet to clear the water lines of bleach. Do not run water into the sink or tub, because the bleach can damage the septic system. A small amount from the water lines inside the house will go into the septic system, but this cannot be avoided.
5. Before using the water, let each inside faucet run until no strong bleach odor is detected. A slight chlorine smell and taste may be present in the water after chlorination; however, this will leave after a short period of time. Another coliform bacteria test is recommended after about 30 days, or sooner, if no chlorine odor is detected.
6. See diagram for proper spring construction.

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• North Carolina Environmental Health Website
• North Carolina Environmental Health Administrative Rules
• North Carolina Division of Water Quality
• What's in your Water
• Water Quality & Health Council