Plain-English guides to water & compliance.
Straight answers on drinking water safety and the rules water systems have to follow — written for the people who drink the water and the operators who protect it.
Boil water notice: what it means and what to do
What a boil water advisory means, exactly what's safe, how long to boil, how long it lasts, and why systems issue one.
Coliform bacteria in water: what a positive result means
Total coliform vs fecal coliform vs E. coli, what a positive test means, and how to fix coliform in well water.
Nitrate in drinking water: limits, risks & what to do
The 10 mg/L EPA limit, why nitrate is an acute risk to infants, where it comes from, how systems remove it, and the 24-hour notice an exceedance requires.
Arsenic in drinking water: limits, risks & removal
The 0.010 mg/L (10 ppb) EPA limit, why arsenic is a chronic cancer risk, where it comes from, how systems remove it, and the Tier 2 30-day notice an exceedance requires.
Turbidity in drinking water: NTU limits & the SWTR
The 0.3 NTU / 1 NTU Surface Water Treatment Rule limits for filtered surface-water and GWUDI systems, why turbidity shields pathogens from disinfection, and what an exceedance triggers.
The Ground Water Rule: what it requires of ground water systems
How 40 CFR 141 Subpart S protects ground water systems from fecal contamination — sanitary surveys, triggered source-water monitoring after a coliform-positive, and corrective action.
Fluoride in drinking water: limits, notices & 0.7 mg/L
The three fluoride numbers — the enforceable 4.0 mg/L MCL, the 2.0 mg/L secondary standard and its special notice, and the 0.7 mg/L fluoridation recommendation — plus where fluoride comes from.
Radionuclides in drinking water: limits, risks & removal
The four EPA limits under 40 CFR § 141.66 — radium, gross alpha, beta/photon, and uranium — the chronic cancer and kidney risks, how systems remove them, and the notice an exceedance requires.
Copper in drinking water: limits, stains & what to do
The 1.3 mg/L copper action level (not a normal MCL), why blue-green stains signal it, its health effects, and what a household and a water system should do.
Backflow prevention: how it works and why it matters
The two causes of backflow, the types of backflow preventers, testing requirements, and cross-connection control.
PFAS in drinking water: limits, deadlines, and treatment
The EPA PFAS limits, the current 2026 status of the rule and compliance deadlines, who must test, and how utilities remove PFAS.
Lead service line inventory: LCRI requirements & deadlines
What the LCRI requires, the November 1, 2027 deadline, the four material classifications, and how to build your inventory.
Water operator certification: how to get licensed
How to become a certified water operator — exam and experience requirements, certification classes, reciprocity, and renewal.
Sanitary survey: the 8 elements and how to prepare
The eight elements a sanitary survey evaluates, how often surveys happen, and how to prepare for yours.
Chlorine residual: free vs total, levels & why it matters
Free vs total vs combined chlorine, target residual levels, the 4.0 mg/L maximum, and how to measure it.