40 CFR § 141.560 National Primary Drinking Water Regulations

§ 141.560 Is my system subject to individual filter turbidity requirements?

Current through Aug 22, 2025 · Read all of Part 141

If your system is a subpart H system serving fewer than 10,000 people and utilizing conventional filtration or direct filtration, you must conduct continuous monitoring of turbidity for each individual filter at your system. The following requirements apply to continuous turbidity monitoring:

(a) Monitoring must be conducted using an approved method in § 141.74(a);

(b) Calibration of turbidimeters must be conducted using procedures specified by the manufacturer;

(c) Results of turbidity monitoring must be recorded at least every 15 minutes;

(d) Monthly reporting must be completed according to § 141.570; and

(e) Records must be maintained according to § 141.571.

← § 141.553 My system practices lime softening—is there any special provision regarding my combined filter effluent?§ 141.561 What happens if my system's turbidity monitoring equipment fails? →