New York Codes, Rules and Regulations › Title 10 - DEPARTMENT OF HEALTH › Chapter I - State Sanitary Code › Part 5 - Drinking Water Supplies › Subpart 5-1 - Public Water Systems › Planning, Siting, Treatment and Approval › Section 5-1.30 - Providing treatment for public water systems

Current through Register Vol. 46, No. 28, July 10, 2024
The supplier of water shall provide such treatment as
						necessary to deliver to the consumer a water conforming to the requirements of
						this section and determined using an approved method, with method modifications
						as listed in the tables in section
						5-1.52  of this
						Subpart, and by an approved laboratory as described in section
						5-1.74  of
						this Subpart.
(a) Minimum treatment
					 for a ground water source shall be disinfection by chlorination or other
					 microbial contaminant treatment acceptable to the State in accordance with the
					 provisions of section
					 5-1.22 
					 of this Subpart. If chemical disinfection is used, the disinfectant residual
					 concentration must be maintained at all times and under no circumstances shall
					 be less than the required concentration for more than four hours. Unless other
					 corrective action is approved by the State, any ground water source where fecal
					 contamination has been observed, or where a significant deficiency may be
					 causing or has the potential to cause the introduction of contamination into
					 the water delivered to customers, must be treated to remove or inactivate 99.99
					 percent (four-log) of viruses. Continuous monitoring of active microbial
					 treatment processes is required, except as provided in section
					 5-1.52  table 15
					 of this Subpart.
(b) Minimum
					 treatment for surface water sources or ground water sources directly influenced
					 by surface water shall be filtration and disinfection techniques, approved by
					 the State in accordance with section
					 5-1.22 
					 of this Subpart, capable of at least 99 percent removal of
Cryptosporidium oocysts,
99.9 percent removal and/or
					 inactivation of
Giardia lamblia
cysts, and 99.99 percent
					 removal and/or inactivation of viruses, between a point where the raw water is
					 no longer subject to recontamination by surface water runoff and a point
					 downstream before or at the first consumer. Compliance with this treatment
					 technique is required for surface water sources or within 18 months after
					 ground water sources are determined to be directly influenced by surface water,
					 unless the department determines that the supplier of water can meet specific
					 avoidance criteria as defined in subdivision (c) of this section. Required
					 performance monitoring shall be conducted in accordance with section
					 5-1.52  table
					 10A of this Subpart. Compliance with these treatment technique requirements
					 shall also include:
(1) filtration facilities
					 designed and operated to meet performance standards in accordance with section
					 5-1.52  table 4A
					 of this Subpart;
(2) for systems
					 using chlorine, the free chlorine residual disinfection concentration in the
					 water entering the distribution system must be at least 0.2 milligrams per
					 liter and may not be less than the required minimum concentration for
					 compliance for more than four hours. Systems using other chemical disinfectants
					 shall maintain residual disinfection levels entering the distribution system
					 comparable to requirements for systems using chlorination. Continuous
					 monitoring is required, except as provided in section
					 5-1.52  table 15
					 of this Subpart; and
(3) by June 8,
					 2004, any system that recycles spent filter backwash water, thickener
					 supernatant, or liquids from dewatering process must return these flows through
					 the processes of a system's existing conventional or direct filtration
					 system.