16 Del. Admin. Code § 4464-8.0

Current through Register Vol. 28, No. 7, January 1, 2025

Section 4464-8.0 - Potable Water Supply, Pool Water Quality/testing, Chemicals And Wastewater

8.1 Potable Water Supply

8.1.1 All pools shall have a water supply which:

8.1.1.1 is approved by the Division;

8.1.1.2 is in compliance with the requirements of the "State of Delaware Regulations Governing Public Drinking Water Systems;"

8.1.1.3 and is of adequate capacity to meet peak demands while maintaining at least twenty five (25) pounds per square inch (psi) and not more than one hundred (100) psi at all points in the system.

8.1.2 All drinking fountains shall be in good working order.

8.1.3 Cross connections between the potable water supply and the pool water shall be prohibited.

8.1.4 Hose bibs shall be located such that they do not constitute a tripping hazard and shall be equipped with vacuum breakers or other backflow prevention devices approved by the Division.

8.2 Fillspout

8.2.1 All pools shall have a permanent fillspout which shall be air gapped at least two (2) pipe diameters above the pool rim, or the rim of any vessel or pipe that connects to the pool.

8.2.2 In order to minimize the possibility of creating a tripping hazard, all fillspouts that are on the deck shall be located immediately next to one of the pool ladders, or another approved location.

8.2.3 The portion of the water line passing through a concrete deck shall either be non-plastic piping or shall be inside a metal sleeve.

8.2.4 All pools that have a fillspout that is a potential tripping hazard, shall take whatever steps are appropriate to eliminate the hazard.

8.3 Clarity

8.3.1 The water in all pools shall be sufficiently clear and the lighting shall be sufficient such that all areas of the pool, and either of the following are clearly visible from the deck:

8.3.1.1 the main drain(s) and all bottom markings;

8.3.1.2 or a black disk six (6) inches in diameter superimposed upon a white field and placed on the bottom at the deepest point.

8.3.2 The turbidity of the pool water shall be five tenths (.5) NTU or less.

8.4 Bacteriological Quality

8.4.1 If samples are taken for the heterotrophic plate count test [standard plate count (SPC)], the result shall be less than (<) two hundred (200) colonies per milliliter.

8.4.2 If samples are taken for the total coliform test, when the membrane filtration (MF) technique is used, the result shall be less than (<) one (1) colony per one hundred (100) milliliters of sample,

8.4.3 when the multiple tube fermentation or most probable number (MPN) method is used, none of the confirmed portions shall show the presence of the coliform group [result reported as less than (<) 2.2] and when the presence/absence test is used, the result shall be absent.

8.4.4 Samples shall be taken by, or required by the Division whenever it is deemed necessary. For the purpose of determining compliance with this Section, samples may be considered only if they have been analyzed by the Division or by another approved laboratory.

8.5 Chemical Quality

8.5.1 The chemical quality of pool water shall not cause any irritation to the eyes or skin of bathers and shall be in compliance with the requirements of the "State of Delaware Regulations Governing Public Drinking Water Systems."

8.5.1.1 The pH shall not be less than 7.2 or greater than 7.8.

8.5.1.2 Any chemical added directly or indirectly to a pool shall be approved by the Division, registered with the U. S. Environmental Protection Agency, used strictly in accordance with the manufacturer's directions and properly labeled in accordance with the Hazardous Chemical Information Act16Del.C.Ch. 24.

8.5.2 Any pool with a documented history of pH level violations shall have an automatic pH adjustment chemical feeder that:

8.5.2.1 is the NSF listed; is approved by the Division;

8.5.2.2 has approved anti-siphon protection; and is wired such that it feeds only when the recirculation pump runs (shall be done on all pools which are in existence on the effective date of these Regulations when either the chemical feeder or recirculation pump are replaced).

8.5.3 The manual addition of approved non-disinfectant chemicals shall be permitted only in special situations (e.g. trying to achieve water balance), which require that the pool be closed.

8.5.3.1 After this manual addition has been completed, the pool shall remain closed for at least one (1) turnover and until such time as the chemical is thoroughly and evenly dispersed throughout the pool.

8.6 Disinfection

8.6.1 All pools shall be disinfected with an approved halogen that imparts an easily measured residual and is fed through an automatic feeder that:

8.6.1.1 is NSF listed; is approved by the Division; has approved anti-siphon protection;

8.6.1.2 is capable of providing a dosage of at least ten (10) ppm for outdoor pools and a dosage of five (5) ppm for indoor pools (shall be done on an existing pool when the disinfectant feeder is replaced);

8.6.1.3 and is wired such that it feeds only when the recirculation pump runs (shall be done on all pools which are in existence on the effective date of these Regulations when either the disinfectant feeder or recirculation pump are replaced).

8.6.2 A flow-through (erosion) feeder shall feed only the disinfectant(s) specified by the manufacturer. All feeders, with the exception of flow-through feeders, shall add the disinfectant downstream from the filter and heater.

8.6.3 All pool disinfectants shall be registered with the U.S. Environmental Protection Agency and approved by the Division.

8.6.4 Manual addition of an approved halogen disinfectant shall be permitted only in special situations (e.g. superchlorination), which require that the pool be closed.

8.6.4.1 After this manual addition has been completed, the pool shall remain closed: for at least one (1) turnover and until such time as the chemical is thoroughly and evenly dispersed throughout the pool;

8.6.4.1.1 and the automatic feeder is operating properly if it was not at the time of the manual addition.

8.6.5 Use of gas chlorine shall be prohibited.

8.6.6 Use of stabilized chlorine (cyanuric acid) in indoor pools shall be prohibited.

8.6.7 In order for any non-halogen to be approved as a stand alone disinfectant, satisfactory performance shall be demonstrated during an NSF evaluation.

8.6.8 All pools shall be disinfected in accordance with the following requirements:

8.6.8.1 Chlorine

8.6.8.1.1 Pools not using Cyanuric Acid minimum 1.0 PPM Free Available Chlorine required

8.6.8.1.2 Pools using Cyanuric Acid minimum 2.0 PPM Free Available Chlorine Required

8.6.8.1.3 Spas minimum 3.0 PPM Free Available Chlorine

8.6.8.1.4 Recommended maximum is 10.0 PPM Free Available Chlorine

8.6.8.2 Bromine

8.6.8.2.1 Pools minimum 3.0 PPM Bromine

8.6.8.2.2 Spas minimum 4.0 PPM Bromine

8.6.8.2.3 Cyanuric Acid should not exceed 100 PPM

8.6.9 Secondary Disinfection Systems

8.6.9.1 General Requirements

8.6.10 ANSI Listing and Labeling - Secondary Disinfection Systems shall be listed and labeled to ANSI/NSF 50 by an ANSI-accredited certification organization approved by the Division.

8.6.10.1 Required Facilities

8.6.10.1.1 The new construction or substantial alteration of the following public pools shall be required to use a secondary disinfection system after adoption of this regulation:

8.6.10.1.2 Pools designed primarily for children under 5 years old, such as

8.6.10.1.2.1 Wading pools

8.6.10.1.2.2 Splash pads with no standing water

8.6.10.1.2.3 Treatment pools

8.6.10.2 3-log Inactivation

8.6.10.2.1 Secondary disinfection system shall be designed to achieve a minimum 3-log (99.9%) reduction in the number of infective Cryptosporidium parvum oocysts per pass through the secondary disinfection system.

8.6.10.3 Installation

8.6.10.3.1 The secondary disinfection system shall be located in the treatment loop (post filtration) and treat a portion (up to 100%) of the filtration flow prior to return of the water to the pool or feature.

8.6.10.3.2 Minimum Flow Rate Calculation The flow rate (Q) through the secondary disinfection system shall be determined based upon the total volume of the pool or feature (V) and a prescribed dilution time (T) for theoretically reducing the number of assumed infective Cryptosporidium (108 oocysts from an initial total number of 100 million) oocysts to a concentration of one oocysts/100 mL.

8.6.10.3.3 Equation Accounting for a 3 log (99.9%) reduction of infective Cryptosporidium oocysts through the secondary disinfection system with each pass, the secondary disinfection system flow rate

8.6.10.3.3.1 (Q) shall be: Q = V x {[14.8 - ln (V)] / (60 x T)}, where:

8.6.10.3.3.1.1 Q = secondary disinfection system flow rate (gpm)

8.6.10.3.3.1.2 V = Total water volume of the pool or feature, including surge tanks, piping, equipment, etc. (gals)

8.6.10.3.3.1.3 T = Dilution time (hrs.)

8.6.10.3.4 Time for Dilution Reduction The dilution time shall be the lesser of nine hours or 75% of the uninterrupted time a pool is closed in a 24 hour period.

8.6.10.3.5 Flow Rate Measurements where a secondary disinfection system is installed, a means shall be installed to confirm the required flow rate to maintain a minimum 3 log (99.9%) reduction of infective Cryptosporidium oocysts at the minimum flow rate.

8.6.11 Water Testing Equipment and Sampling Frequency

8.6.11.1 All pools shall have approved testing equipment for pH, disinfectant residual, alkalinity, and calcium hardness.

8.6.11.2 For disinfectant residual, the DPD (Diethyl-P-Phenylene Diamine) method, or any other method in the current edition of Standard Methods for the Examination of Water and Wastewater, shall be used.

8.6.11.3 If the disinfectant is chlorine, the test kit shall be capable of measuring both free and total chlorine residual.

8.6.11.4 For pH, the phenol red colorimetric method, or any other method in the current edition of Standard Methods for the Examination of Water and Wastewater, shall be used and the test kit shall have a range of at least 6.8-8.2.

8.6.11.5 In addition to these parameters, pools that use a stabilized halogen shall have approved cyanuric acid testing equipment.

8.6.11.6 All chemical test kit reagents shall be dated when received, and shall be replaced just prior to the start of each outdoor pool season, and at least yearly for indoor pools, with the exception of phenol red which shall be replaced at least every six (6) months.

8.6.11.6.1 pH and disinfectant residual shall be measured daily, prior to the pool opening, and as often as necessary while the pool is open (recommended every one (1) to two (2) hours) in order to ensure the proper levels.

8.6.11.6.2 Alkalinity, calcium hardness and cyanuric acid (if applicable) shall be measured after each addition of makeup water and at least weekly.

8.6.12 All sample results shall be recorded along with the date, time and sample location (area of the pool).

8.6.13 Records of sample results shall be kept at the pool for at least one (1) year, shall be available for viewing by any representative of the Division during an inspection and shall be submitted to the Division upon request.

8.6.14 If any other substance is added to the pool on a regular basis (e.g. copper/silver from a supplemental disinfection system), the Division may require testing to ensure that the concentrations do not exceed acceptable levels.

8.7 Pool Water Level and Recirculation System

8.7.1 When the pool is open, the pool water level shall be maintained at an elevation suitable for continuous flow into the surface skimmers or intermittent flow into the gutter as bathers enter.

8.7.2 The recirculation system shall operate continuously (24 hours per day), with the exception of the automatic disinfectant feeder when the disinfectant level approaches or exceeds the upper recommended level.

8.7.3 All pools shall have the capability of pumping water to waste either directly or via filter backwash.

8.7.4 The Division may require a dye test to ensure that the recirculation system is providing even and complete recirculation throughout the pool.

8.8 Chemical Storage

8.8.1 All chemicals, including test kits, shall be stored in accordance with the storage recommendations on the manufacturer's label and the MSDS, and they shall be stored in areas that are not easily accessible to bathers or other unauthorized personnel.

8.8.2 All pools shall keep adequate quantities of chemicals on hand such that shortages are not experienced.

8.8.3 "NO SMOKING" signs shall be conspicuously posted in all chemical storage areas.

8.9 Wastewater Disposal

8.9.1 Cross connections between the pool recirculation system and any wastewater system, including the filter backwash drain, shall be prohibited.

8.9.2 The backwash discharge line shall terminate above the drain entry point by a distance of at least twice its diameter.

16 Del. Admin. Code § 4464-8.0

19 DE Reg. 309( 10/1/2015) (Final)