Hurricane Response Guide for Environmental Public Health Professionals
General Sampling Procedures 1. Prepare a Sampling and Analysis Plan (SAP) detailing sampling locations, types, numbers, and quality control requirements. 2. Coordinate with the lab on acceptable equipment, preservatives, and procedures. Use lab-provided supplies if possible. 3. Handle dangerous acid and base preservatives with care. Wear gloves and eye protection. Have neutralization supplies ready. 4. Collect samples in a clean area free of contamination. 5. Select a clean, cold water faucet free of contaminating devices. Ensure the faucet is in good condition. 6. Use a faucet tall enough to fill sample bottles without physically contacting them. 7. Flush the faucet for 2-3 minutes until the temperature stabilizes. Adjust flow to avoid splashing. 8. Follow the provided collection instructions for each analyte. Wear gloves and eye protection. 9. For Lead and Copper Rule compliance: a. Select a faucet without water-altering devices. Do not remove screens or aerators. b. For the first flush, let water sit ≥ 6 hrs. Collect the first water for 1L sample. c. For the lead service line, collect 8–10 sequential samples. See EPA guidance for details. 10. Fill out a chain of custody form with all pertinent collection information. 11. Deliver/ship samples to meet holding time requirements. 12. Return empty preservative containers to the lab for disposal. Water Treatment Steps Public water systems use a series of treatment steps to provide safe drinking water: 1. Coagulation: Chemicals with a positive charge are added to neutralize negative charges on dissolved particles, causing them to bind together. 2. Flocculation: Gentle mixing helps form larger, heavier particles called flocs. 3. Sedimentation: The heavy flocs settle to the bottom, separating from the clear water. 4. Filtration: The clear water passes through filters of varying pore sizes and materials to remove dissolved particles, chemicals, parasites, bacteria, and viruses. Advanced methods like ultrafiltration and reverse osmosis may also be used. 5. Disinfection: Chemical disinfectants (i.e., chlorine, chloramine, chlorine dioxide) are added to kill the remaining microbes. Ultraviolet (UV) light or ozone can also be used. Low levels of disinfectant remain to continue killing germs as water travels through pipes. The pH is often adjusted, and fluoride is added after disinfection to improve taste, reduce pipe corrosion, and keep teeth strong. Treatment varies by community, depending on the source of water. Surface water usually requires more treatment than groundwater because it contains more contaminants. Special methods may be needed if the water contains radionuclides, nitrates, or cyanobacterial toxins. Individuals should store 1 gallon of water per person per day (2-week supply) in their homes. Pregnant women, the elderly, service animals or pets, and those living in hot climates may need more than this recommended amount. Bottled Water Unopened, commercially bottled water is a safe, reliable water source in an emergency. Make sure you check the expiration date for store-bought water. Home Preparedness How Much Water to Store
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