Read Only Copy Not For Distribution. Chapter 17. Private Potable Water Supply Systems 17.1 GENERAL REGULATIONS 17.2 QUANTITY OF WATER REQUIRED

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1 Chapter 17 Private Potable Water Supply Systems 17.1 GENERAL REGULATIONS Applicability The regulations in this chapter apply to any private potable water supply system where plumbing fixtures are installed for human occupancy. Comment: This chapter applies to private water supply systems serving one or more buildings independent of any public water supply Pumps Pumps shall be installed only in wells, springs and cisterns that comply with the rules and regulations as determined by the Authority Having Jurisdiction QUANTITY OF WATER REQUIRED Single Dwelling Units The minimum capacity of the system in gallons per minute shall equal the number of fixtures installed. Comment: A capacity of 1 GPM per fixture in a single dwelling unit is a rough rule of thumb. The peak demand should be verified using Tables A and B. See Section where well yields do not satisfy the peak demand Other Than a Single Dwelling Unit In other than a single dwelling unit, the water system shall be designed in accordance with Tables A, and B and shall be capable of supplying the maximum demand to the system according to usage, but, in no case, less than for a minimum period of 30 minutes. Comment: See Section for determining the peak demand on the potable water supply system Available Water Total water available during any 24-hour period shall not be less than the requirements of Table Comment: Table indicates the daily design sewage flows from various establishments. The available water supply must be able to satisfy this daily volume requirement, as well as the peak GPM demand National Standard Plumbing Code - Illustrated 355

2 Secondary Sources of Water a. When the available primary source of water does not meet the minimum requirement of Sections , , and , one of the following methods shall be used: 1. Pressure tank of sufficient size. 2. Gravity tank, see Section Two pump system. (a) The capacity of the first pump shall not exceed the flow capacity of the well. It shall supply water to a tank that stores the water at atmospheric pressure and has a level control to start and stop the pump. (b) The second pump shall supply a hydro-pneumatic tank at the required pressure and volume to supply the water distribution system PRESSURE Comment: Where the primary potable water supply source cannot provide sufficient volume to satisfy the 24-hour demand of the water distribution system, water storage facilities must be provided. Required water supply pressures are as indicated in Sections a and b. Comment: Private potable water supply systems must provide adequate pressure for fixtures to deliver the flow rates for the various fixtures listed in Sections a and b PIPING MATERIALS Piping from a well or other water source to a building water distribution system shall be in accordance with Sections and STORAGE TANKS Storage equipment shall be as follows: Certified Tanks All tanks shall be certified for use with potable water Tank Material All tanks shall be coated or made of material to resist corrosion Pressure Rating Hydropneumatic tanks shall have a working pressure rating in excess of the maximum required system pressure Non-Toxic Materials All tanks shall be constructed of materials and/or coatings that are non-toxic Drain Required All tanks shall be provided with a means for draining Covers Atmospheric storage tanks shall be provided with a cover as required in Section National Standard Plumbing Code - Illustrated

3 17.6 PUMPS Pump Sizing Pumps may be sized as recommended in the Water Systems Council s Water Systems Handbook. Comment #1: Well pumps for private water supplies include shallow well jet pumps, deep well jet pumps, and submersible pumps. Comment #2: Jet pumps circulate water through an ejector fitting that develops a vacuum and draws water from the well. Shallow well jet pumps are used for wells less than 25 feet deep and have the ejector fitting located outside of the well. Deep well jet pumps can be used for wells up to 75 feet deep and have the ejector fitting located within the well casing. Some jet pumps are convertible and can be used for either one-pipe shallow well or two-pipe deep well installations, although their rated capacity is less for deep wells than for shallow wells. Comment #3: Submersible well pumps are located at the bottom of the drop pipe within the well casing. Submersible well pumps can lift water up to 500 feet or more Pump Installation Pumps shall be installed in accordance with the manufacturer s recommendations. and the recommendations in the Water Systems Council s Water Systems Handbook Equipment Installation Pumping equipment shall be installed to prevent the entrance of contamination or objectionable material either into the well or into the water that is being pumped Pump Location Pumps shall be located to facilitate necessary maintenance and repair. Vertical well pumps shall include overhead clearance for removal of drop pipes Pump Mounting Pumps shall be suitably mounted to avoid objectionable vibration and noise, and to prevent damage to pumping equipment Pump Accessories Pump controls and/or accessories shall be protected from weather PUMP DOWN CONTROL Tailpipe Thirty (30) feet of tailpipe shall be installed below the jet on deep well installation Switches A low pressure cut-off switch and/or water level cut-off switch shall be installed Suction Pipe Provide a vertical suction pipe of 30-foot length on shallow well jet installation National Standard Plumbing Code - Illustrated 357

4 17.8 CONTROLS a. The following controls are required on all pump installations: 1. Pressure switch 2. Thermal overload switch 3. Pressure relief valve on positive displacement pumps 4. Low water cut-off switch where the pump capacity exceeds the source of water WELL TERMINAL Upper Well Terminal Well casings and curbs shall terminate not less than eight inches above the finished ground surface or pump house floor and at least 24 inches above the maximum high water level where flooding occurs. No casing shall be cut off or cut into below ground level except to install a pitless adapter Pitless Adapter Design Pitless adapters designed to replace a section of well casing or for attachment through the wall of the well casing shall be constructed of materials that provide strength and durability equal to the well casing Installation Installation shall be by a threaded or welded adapter or a coupling connection to the casing or attachment through the wall of the casing and shall be watertight Adapter Units Adapter units designed to replace a section of the well casing shall extend above the finished ground surface as provided in Section The top of the adapter unit shall be capped with a cover having a downward flange that will overlap the edge of the unit. The cover shall be securely fastened to the unit and shall fit sufficiently snug to the unit to be vermin proof. The cover shall provide for watertight entrance of electrical cables and vent piping or air line if installed Hand Pumps General Hand pumps shall be of the force type equipped with a packing gland around the pump rod, a delivery spout that is closed and downward directed, and a one-piece bell type base that is part of the pump stand or is attached to the pump column in a watertight manner Installation The bell base of the pump shall be bolted with a gasket to a flange that is securely attached to the casing or pipe sleeve Power Driven Pumps General The design and operating principles of each type of power driven pump determines where each may be located with respect to a well. The location selected for the pump determines what factors must be considered to make an acceptable installation National Standard Plumbing Code - Illustrated

5 Location Above Well Any power driven pump located over a well shall be mounted on the well casing, pipe sleeve, pump foundation or pump stand such that a watertight closure is or can be made with the open top of the casing or sleeve Pump Base The pump base bolted with a neoprene or rubber gasket or equivalent watertight seal to a foundation or plate provides an acceptable seal Large Pump Installation On large pump installations, the bolting may be omitted when the weight of the pump and column is sufficient to make a watertight contact with the gasket Pump Location Other Than Over Casing If the pump unit is not located over the casing or pipe sleeve, and the pump delivery or suction pipes emerge from the top of the well, a watertight expanding rubber seal or equivalent shall be installed between the well casing and piping to provide a watertight closure Seal Top The top of the seal in Section shall not extend below the uppermost edge of the casing or pipe sleeve Location in Well For Submersible Pumps General This type of location is permissible for submersible pumps only Top Discharge Line When the discharge line leaves the well at the top of the casing, the opening between the discharge line and casing or pipe sleeve shall be sealed watertight with an expanding rubber seal or equivalent device Underground Discharge When an underground discharge is desired, a properly installed pitless adapter shall be used. A check valve shall be installed in the discharge line above the pump in the well Top Discharge Line Sloped to Drain to Well When the discharge pipe leaves the well at the top, remains above ground, and slopes to drain back to the well, the check valve can be located beyond the well Offset from Well Location Pumps offset from the well, if not located in an above-ground pump house or other building, may be located in an approved basement provided the pump and all suction pipes are elevated at least 12 inches above the floor Buried Lines All portions of suction lines buried below the ground surface between the well and the pump and that are not enclosed in a protective pipe shall be located the same minimum distance from sources of contamination as are prescribed for the well in Section Protective Pipe When the minimum distances in Section cannot be obtained, the suction line shall be enclosed in a protective pipe of standard thickness from the well to the pump. The protective pipe shall be sealed watertight at both ends National Standard Plumbing Code - Illustrated 359

6 17.10 VENTS Size All vent piping shall be of adequate size to allow equalization of air pressure in the well and shall not be less than one-half inch in diameter Toxic or Flammable Gases Particular attention shall be given to proper venting of wells and pressure tanks in areas where toxic or flammable gases are known to be a characteristic of the water. If determined that either of these types of gases are present, all vents when located in buildings shall be extended to discharge outside of the building at a height where they will not be a hazard Vent Extension The vent shall extend above the upper terminal of the well with the end down turned and covered with not less than 16 mesh screen wire. The point of entry into the well shall be sealed watertight BEARING LUBRICATION General Lubrication of bearings of power driven pumps shall be with water or oil that will not adversely affect the quality of the water to be pumped Water Lubrication If a storage tank is required for the lubrication water, it shall be designed to protect the water from contamination Oil Lubrication The reservoir shall be designed to protect the oil from contamination. The oil shall not contain substances that will cause odor or taste to the water pumped WATER LEVEL MEASUREMENT On wells of large capacity where access for measuring the water level in the well is provided, piping for this purpose shall terminate above the upper well terminal, be capped or otherwise closed, and all openings around the piping at the point of entry into the well sealed watertight PROHIBITED PUMPS No pitcher or chain-bucket pump shall be installed on any water supply PUMP HOUSING Watertight A separate structure housing the water supply and pumping equipment shall have an impervious floor and rain-tight walls and roof Pump Pit A pump pit shall be of watertight construction and provided with a positive drain or sump pump to keep the pit dry National Standard Plumbing Code - Illustrated

7 17.15 PRIVATE WATER SUPPLY SYSTEM RESTRICTIONS AND LIMITATIONS Restriction A private potable water supply system shall not be connected to a public water supply system unless approved in accordance with Section Limitations No private potable water supply system shall serve more than one property unless approved by the Authority Having Jurisdiction National Standard Plumbing Code - Illustrated 361

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