Title of Rule and Other Identifying Information: Chapter 51-56 WAC, Washington state amendment of the 2009 Uniform
THIS RULE IS BEING PROPOSED UNDER AN EXPEDITED RULE-MAKING PROCESS THAT WILL ELIMINATE THE NEED FOR THE AGENCY TO HOLD PUBLIC HEARINGS, PREPARE A SMALL BUSINESS ECONOMIC IMPACT STATEMENT, OR PROVIDE RESPONSES TO THE CRITERIA FOR A SIGNIFICANT LEGISLATIVE RULE. IF YOU OBJECT TO THIS USE OF THE EXPEDITED RULE-MAKING PROCESS, YOU MUST EXPRESS YOUR OBJECTIONS IN WRITING AND THEY MUST BE SENT TO Tim Nogler, Managing Director, Washington State Building Code Council, P.O. Box 41449, Olympia, WA 98504-1449 , AND RECEIVED BY November 10, 2011.
Purpose of the Proposal and Its Anticipated Effects, Including Any Changes in Existing Rules: WAC 51-56-0600, in Section 601.2.2 language was added to clarify that markings required for rainwater piping in Chapter 16 do not conflict with the marking requirements in Chapter 6. (OTS 4106.1)
WAC 51-11-1600, Section 1617.2.1 was modified to require pipe markings per industry standards. Section 1617.2.2 was amended to specify purple markings for rainwater system piping, per industry standards, as were Sections 1628.6.3 and 1629.2. (OTS 4107.1)
Reasons Supporting Proposal: Some editorial errors were identified in the rules filed under WSR 10-03-101. This rule corrects those errors.
Statutory Authority for Adoption: RCW 19.27A.025, 19.27A.045.
Statute Being Implemented: Chapters 19.27, 19.27A, and 34.05 RCW.
Rule is not necessitated by federal law, federal or state court decision.
Name of Proponent: State building code council, governmental.
Name of Agency Personnel Responsible for Drafting and Implementation: Krista Braaksma, P.O. Box 41449, Olympia, WA 98504-1449, (360) 407-9278; and Enforcement: Local jurisdictions.
September 6, 2011
AMENDATORY SECTION(Amending WSR 10-03-101, filed 1/20/10, effective 7/1/10)
WAC 51-56-0600 Chapter 6 -- Water supply and distribution. 601.1 Except where not deemed necessary for safety or sanitation by the AHJ, each plumbing fixture shall be provided with an adequate supply of potable running water piped thereto in an approved manner, so arranged as to flush and keep it in a clean and sanitary condition without danger of backflow or cross-connection. Water closets and urinals shall be flushed by means of an approved flush tank or flushometer valve.
|EXCEPTION:||Listed fixtures that do not require water for their operation and are not connected to the water supply.|
601.2.2 Color and Information. Each system shall be identified with a colored pipe or band and coded with paints, wraps and materials compatible with the piping.
Except as required in Chapter 16, nonpotable water systems shall have a yellow background with black uppercase lettering, with the words "CAUTION: NONPOTABLE WATER, DO NOT DRINK." Each nonpotable system shall be identified to designate the liquid being conveyed, and the direction of normal flow shall be clearly shown. The minimum size of the letters and the length of color field shall conform to Table 6-1.
The background color and required information shall be indicated every twenty (20) feet (6,096 mm) but not less than once per room, and shall be visible from the floor level.
603.0 Cross-Connection Control. Cross-connection control shall be provided in accordance with the provisions of this chapter. Devices or assemblies for protection of the public water system must be models approved by the department of health under WAC 246-290-490. The authority having jurisdiction shall coordinate with the local water purveyor where applicable in all matters concerning cross-connection control within the property lines of the premises.
No person shall install any water operated equipment or mechanism, or use any water treating chemical or substance, if it is found that such equipment, mechanism, chemical or substance may cause pollution or contamination of the domestic water supply. Such equipment or mechanism may be permitted only when equipped with an approved backflow prevention device or assembly.
603.1 Approval of Devices or Assemblies. Before any device or assembly is installed for the prevention of backflow, it shall have first been approved by the authority having jurisdiction. Devices or assemblies shall be tested for conformity with recognized standards or other standards acceptable to the authority having jurisdiction. Backflow prevention devices and assemblies shall comply with Table 6-2, except for specific applications and provisions as stated in Section 603.4 through 603.4.22.
All devices or assemblies installed in a potable water supply system for protection against backflow shall be maintained in good working condition by the person or persons having control of such devices or assemblies. Such devices or assemblies shall be tested in accordance with Section 603.3.3 and WAC 246-290-490. If found to be defective or inoperative, the device or assembly shall be replaced or repaired. No device or assembly shall be removed from use or relocated or other device or assembly substituted, without the approval of the authority having jurisdiction.
Testing shall be performed by a Washington state department of health certified backflow assembly tester.
Backflow Prevention Devices, Assemblies and Methods
The following line is deleted from the table:
|Device, Assembly or Method||Applicable Standards||Pollution (Low Hazard)||Contamination (High Hazard)||
|Back Siphonage||Back Pressure||Back Siphonage||Back Pressure|
|Backflow preventer for carbonated beverage dispensers (two independent check valves with a vent to the atmosphere.)||ASSE 1022||X||Installation includes carbonated beverage machines or dispensers. These devices operate under intermittent or continuous pressure conditions.|
(1) At the time of installation, repair or relocation; and
(2) At least on an annual schedule thereafter, unless more frequent testing is required by the authority having jurisdiction.
603.4.6.1 Potable water supplies to systems having no pumps or connections for pumping equipment, and no chemical injection or provisions for chemical injection, shall be protected from backflow by one of the following devices:
(1) Atmospheric vacuum breaker.
(2) Pressure vacuum breaker.
(3) Spill-resistant pressure vacuum breaker.
(4) Reduced pressure backflow preventer.
(5) A double check valve may be allowed when approved by the water purveyor and the authority having jurisdiction.
603.4.10 Potable Water Make Up Connections to Steam or Hot Water Boilers shall be protected by an air gap or a reduced pressure principle backflow preventer.
603.4.12 Potable Water Supply to Carbonators shall be protected by a listed reduced pressure principle backflow preventer as approved by the authority having jurisdiction for the specific use. The backflow preventer shall be located in accordance with Section 603.3.4. The piping downstream of the backflow preventer shall not be of copper, copper alloy, or other material that is affected by carbon dioxide.
603.4.14 Backflow preventers shall not be located in any area containing fumes or aerosols that are toxic, poisonous, infectious, or corrosive.
603.4.16.1 Except as provided under Sections 603.4.16.2 and 603.4.16.3, potable water supplies to fire protection systems that are normally under pressure, including but not limited to standpipes and automatic sprinkler systems, except in one or two family residential flow-through or combination sprinkler systems piped in materials approved for potable water distribution systems, shall be protected from back-pressure and back-siphonage by one of the following testable devices:
1. Double check valve assembly.
2. Double check detector assembly.
3. Reduced pressure backflow preventer.
4. Reduced pressure detector assembly.
Potable water supplies to fire protection systems that are not normally under pressure shall be protected from backflow and shall meet the requirements of the appropriate standard(s) referenced in Table 14-1.
604.15 Plastic water service piping may terminate within a building, provided the connection to the potable water distribution system shall be made as near as is practical to the point of entry and shall be accessible. Barbed insert fittings with hose clamps are prohibited as a transition fitting within the building.
608.5 Relief valves located inside a building shall be provided with a drain, not smaller than the relief valve outlet, of galvanized steel, hard drawn copper piping and fittings, CPVC, or listed relief valve drain tube with fittings which will not reduce the internal bore of the pipe or tubing (straight lengths as opposed to coils) and shall extend from the valve to the outside of the building, with the end of the pipe not more than two (2) feet (610 mm) nor less than six (6) inches (152 mm) above the ground or the flood level of the area receiving the discharge and pointing downward. Such drains may terminate at other approved locations. No part of such drain pipe shall be trapped or subject to freezing. The terminal end of the drain pipe shall not be threaded.
|EXCEPTION:||Replacement water heating equipment shall only be required to provide a drain pointing downward from the relief valve to extend between two feet (610 mm) and six inches (152 mm) from the floor. No additional floor drain need be provided.|
Listed parallel water distribution systems shall be installed in accordance with their listing.
[Statutory Authority: RCW 19.27.074, 19.27.031 and chapters 19.27 and 34.05 RCW. 10-03-101, § 51-56-0600, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.190, 19.27.020 and chapters 19.27 and 34.05 RCW. 07-01-094, § 51-56-0600, filed 12/19/06, effective 7/1/07. Statutory Authority: RCW 19.27.031 and 19.27.074. 04-01-110, § 51-56-0600, filed 12/17/03, effective 7/1/04; 02-01-114, § 51-56-0600, filed 12/18/01, effective 7/1/02.]
AMENDATORY SECTION(Amending WSR 10-03-101, filed 1/20/10, effective 7/1/10)
WAC 51-56-1600 Chapter 16 -- Gray water systems.
Part I, Gray Water Systems, is not adopted. Gray water shall not be used for irrigation except as permitted by the department of health rules.
1613. Nonpotable Reuse Water Systems -- General.
(A) The provisions of Part II of this chapter shall apply to the installation, construction, alteration, and repair of nonpotable reuse water intended to supply uses such as water closets, urinals, and trap primers for floor drains, and floor sinks, irrigation, industrial processes, water features and other uses approved by the Authority Having Jurisdiction. Potable water supplied as makeup water in these systems shall be protected against back-pressure and backsiphonage in accordance with Sections 602.0 and 603.0.
(B) No permit for any nonpotable reuse water system shall be issued until complete plumbing plans, with appropriate data satisfactory to the Authority Having Jurisdiction, have been submitted and approved. No changes or connections shall be made to either the nonpotable water system or the potable water system within any site containing a nonpotable reuse water system without approval by the Authority Having Jurisdiction.
(C) Before the building is occupied, the installer shall perform the initial cross-connection test in the presence of the Authority Having Jurisdiction and other authorities having jurisdiction. The test shall be ruled successful by the Authority Having Jurisdiction before final approval is granted.
(D) A nonpotable reuse water system shall be designed by a person registered or licensed to perform plumbing design work.
1614.0 Definitions. Nonpotable reuse water shall include the following:
Reclaimed Water - Water derived in any part from wastewater with a domestic wastewater component that has been adequately and reliably treated, so that it can be used for beneficial purposes. Reclaimed water is not considered a wastewater (RCW 90.46.010);
Greywater or Gray Water - Domestic type flows from bathtubs, showers, bathroom sinks, washing machines, dishwashers, and kitchen or utility sinks. Gray water does not include flow from a toilet or urinal (RCW 90.46.010); and
Other nonpotable wastewater sources from appliances and fixtures excluding wastewater streams containing black water.
For rainwater harvesting, see Part III.
1615.0 Permit. It shall be unlawful for any person to construct, install, alter, or cause to be constructed, installed, or altered any nonpotable reused water system within a building or on a premises without first obtaining a permit to do such work from the Authority Having Jurisdiction.
1616.0 Drawings and Specifications. The Authority Having Jurisdiction shall be permitted to require any or all of the following information to be included with or in the plot plan before a permit is issued for a nonpotable reused water system.
(A) A plot plan drawn to scale and completely dimensioned, showing lot lines and structures, location of present and proposed potable water supplies and meters, water wells, streams, auxiliary water supply and systems, nonpotable reused water supply and meters, drain lines, and locations of private sewage disposal systems and 100 percent expansion areas or building sewer connected to the public sewer.
(B) Details of construction including riser diagrams or isometrics and a full description of the complete installation, including installation methods, construction, and materials as required by the Authority Having Jurisdiction. To the extent permitted by structural conditions, nonpotable reused water risers within the toilet room, including appurtenances such as air/vacuum relief valves, pressure reducing valves, etc., shall be installed in the opposite end of the room containing the served fixtures from the potable water risers or opposite walls, as applicable. To the extent permitted by structural conditions, nonpotable reused water headers and branches off risers shall not be run in the same wall or ceiling cavity of the toilet room where potable water piping is run.
(C) Detailed initial and annual testing requirements as outlined elsewhere in this chapter.
1617.0 Pipe Material/Pipe Identification. Nonpotable reused water systems shall comply with Sections 1617.1 and 1617.2.
1617.1 Pipe Materials. Reclaimed water and nonpotable water reuse pipe, valves and fittings shall conform to the requirements of Sections 604.0, 605.0 and 606.0.
1617.2 Color and Information.
1617.2.1 Reclaimed Water. Reclaimed water systems shall have a purple background with black uppercase lettering with the words "CAUTION: RECLAIMED WATER, DO NOT DRINK." The minimum size of the letters and length of the color field shall conform to Table 6-1. Where used, a colored identification band shall be indicated every twenty feet (6,096 mm) not less than once per room, and shall be visible from the floor level. Where concealed within construction, the piping shall be labeled on two opposing sides of the pipe within each stud or joist bay. Marking is not required for pipe manufactured with purple color integral to the pipe and marked with black uppercase lettering to read "CAUTION: NONPOTABLE RECLAIMED WATER, DO NOT DRINK" in intervals not to exceed five feet (1,524 mm). All valves, except fixture supply control valves shall be equipped with a locking feature. All mechanical equipment that is appurtenant to the reclaimed water system shall be painted purple.
1617.2.2 Other Nonpotable Reused Water. Except as noted in Section 1617.2.1, nonpotable water systems shall have a ((
yellow)) purple background with black uppercase lettering,
with the words "CAUTION: NONPOTABLE WATER, DO NOT DRINK." Each
nonpotable system shall be identified to designate the liquid
being conveyed, and the direction of normal flow shall be
clearly shown. The minimum size of the letters and length of
the color field shall conform to Table 6-1.
The background color and required information shall be indicated every twenty feet but not less than once per room, and shall be visible from the floor level. Where concealed within construction, the piping shall be labeled on two opposing sides of the pipe within each stud or joist bay. All mechanical equipment that is appurtenant to the nonpotable reused water system shall be painted purple.
1618.1 Collection Reservoir. Nonpotable reuse water shall be collected in an approved reservoir constructed of durable, nonabsorbent and corrosion-resistant materials. The reservoir shall be a closed and gas-tight vessel. Access openings shall be provided to allow inspection and cleaning of the reservoir interior. The reservoir shall be sized to limit the retention time of nonpotable reuse water to a maximum of seventy-two hours.
1618.1.1 Filtration. Nonpotable reuse water entering the reservoir shall pass through an approved filter such as a media, sand or diatomaceous earth filter.
1618.1.2 Required Valve. A full-open valve shall be installed downstream of the last fixture connection to the nonpotable reuse water discharge pipe before entering the required filter.
1618.1.3 Overflow. The collection reservoir shall be equipped with an overflow pipe of the same diameter as, or larger than, the influent pipe for the nonpotable reuse water. The overflow shall be indirectly connected to the sanitary drainage system.
1618.1.4 Drain. A drain shall be located at the lowest point of the collection reservoir and shall be indirectly connected to the sanitary drainage system. The drain shall be the same diameter as the overflow pipe required in Section 1618.1.3.
1618.1.5 Disinfection. Nonpotable reuse water shall be disinfected by an approved method that uses one or more disinfectants such as chlorine, iodine or ozone.
1618.1.6 Makeup Water. Potable water shall be supplied as a source of makeup water for nonpotable water systems that serve plumbing fixtures. The potable supply shall be protected against backflow in accordance with Chapter 6. A full-open valve shall be located on the makeup water supply line to the collection reservoir.
(A) Hose bibbs shall not be allowed on nonpotable reuse water piping systems.
(B) The nonpotable reuse water system and the potable water system within the building shall be provided with the required appurtenances (valves, air/vacuum relief valves, etc.,) to allow for deactivation or drainage as required by this chapter for a cross-connection test in Section 1620.0.
(C) Nonpotable reuse water pipes shall not be run or laid in the same trench as potable water pipes. A ten foot (3,048 mm) horizontal separation shall be maintained between pressurized, buried reclaimed and potable water piping. Buried potable water pipes crossing pressurized nonpotable reuse water pipes shall be laid not less than twelve inches (305 mm) above the nonpotable reuse water pipes. Nonpotable reuse water pipes laid in the same trench or crossing building sewer or drainage piping shall be installed in compliance with Sections 609.0 and 720.0 of this code. Nonpotable reuse water pipes shall be protected similar to potable water pipes.
1619.1 Commercial, Industrial and Institutional Room Entrance Signs. In commercial, industrial, and institutional occupancies, all rooms using nonpotable reuse water for water closets and/or urinals shall be identified with signs. Each sign shall contain one-half inch (12.7 mm) letters of a highly visible color on a contrasting background. The location of the sign(s) shall be such that the sign(s) shall be visible to all users. The number and location of the signs shall be approved by the Authority Having Jurisdiction and shall contain the following text:
|TO CONSERVE WATER,
THIS BUILDING USES RECLAIMED WATER TO FLUSH TOILETS AND URINALS.
NONPOTABLE RECLAIMED WATER, DO NOT DRINK.
DO NOT CONNECT TO DRINKING WATER SYSTEM.
CONTACT BUILDING MANAGEMENT BEFORE PERFORMING ANY WORK ON THIS WATER SYSTEM.
1619.3 Where water closets and/or urinals are flushed with nonpotable reuse water, the fixture shall be labeled:
TO CONSERVE WATER, THIS BUILDING USES NONPOTABLE RECLAIMED WATER TO FLUSH TOILETS AND URINALS
1620.0 Inspection and Testing.
1620.1 Nonpotable reuse water piping shall be inspected and tested as outlined in this code for testing of potable water piping.
1620.2 An initial and subsequent annual inspection and test shall be performed on both the potable and nonpotable reuse water systems. The potable and nonpotable reuse water systems shall be isolated from each other and independently inspected and tested to ensure there is no cross-connection as follows:
1620.2.1 Visual Dual System Inspection. Prior to commencing the cross-connection testing, a dual system inspection shall be conducted by the Authority Having Jurisdiction and other authorities having jurisdiction.
(i) Meter locations of the nonpotable reuse water and potable water lines shall be checked to verify that no modifications were made, and that no cross-connections are visible.
(ii) Pumps and equipment, equipment room signs, and exposed piping in the equipment room shall be checked.
(iii) Valves shall be checked to ensure that valve lock seals are still in place and intact. Valve control door signs shall be checked to verify that no signs have been removed.
1620.2.2 Cross-Connection Test. The following procedure shall be followed by the applicant in the presence of the Authority Having Jurisdiction and other authorities having jurisdiction to determine whether a cross connection occurred.
(i) The potable water system shall be activated and pressurized. The nonpotable reuse water system shall be shut down and completely drained.
(ii) The potable water system shall remain pressurized for a minimum period of time specified by the Authority Having Jurisdiction while the nonpotable reuse water system is empty. The minimum period the nonpotable reuse water system is to remain depressurized shall be determined on a case-by-case basis, taking into account the size and complexity of the potable and nonpotable reuse water distribution systems, but in no case shall that period be less than one hour.
(iii) Fixtures, potable and reclaimed, shall be tested and inspected for flow. Flow from any nonpotable reuse water system outlet shall indicate a cross-connection. No flow from a potable water outlet would indicate that it is connected to the nonpotable reuse water system.
(iv) The drain on the nonpotable reuse water system shall be checked for flow during the test and at the end of the period.
(v) The potable water system shall then be completely drained.
(vi) The nonpotable reuse water system shall then be activated and pressurized.
(vii) The nonpotable reuse water system shall remain pressurized for a minimum period of time specified by the Authority Having Jurisdiction while the potable water system is empty. The minimum period the potable water system is to remain depressurized shall be determined on a case-by-case basis, but in no case shall that period be less than one hour.
(viii) Fixtures, potable and reclaimed, shall be tested and inspected for flow. Flow from any potable water system outlet shall indicate a cross-connection. No flow from a nonpotable reuse water outlet would indicate that it is connected to the potable water system.
(ix) The drain on the potable water system shall be checked for flow during the test and at the end of the period.
(x) If there is no flow detected in any of the fixtures that would have indicated a cross-connection, the potable water system shall be repressurized.
1620.2.3 Cross-Connection Discovered. The following procedure, in the presence of the Authority Having Jurisdiction, shall be activated immediately:
(i) Nonpotable reuse water piping to the building shall be shut down at the meter, and the nonpotable reuse water riser shall be drained.
(ii) Potable water piping to the building shall be shut down at the meter.
(iii) The cross-connection shall be uncovered and disconnected.
(iv) The building shall be retested following procedures listed in subsections (B)(1) and (2) above.
(v) The potable water system shall be chlorinated with fifty ppm chlorine for twenty-four hours.
(vi) The potable water system shall be flushed after twenty-four hours, and a standard bacteriological test shall be performed. If test results are acceptable, the potable water system shall be permitted to be recharged.
1620.3 An annual inspection of the nonpotable reuse water system, following the procedures listed in subsection 1620.0 (B)(1), shall be required. Annual cross-connection testing, following the procedures listed in subsection 1620.0 (B)(2), shall be required by the Authority Having Jurisdiction, unless site conditions do not require it. In no event shall the test occur less often than once in four years. Alternate testing requirements shall be permitted by the Authority Having Jurisdiction.
1621.0 Sizing. Nonpotable reuse water piping shall be sized as outlined in this code for sizing potable water piping.
1622.0 Abandonment of Nonpotable Reuse Water Systems. Where nonpotable reuse water systems are abandoned, the procedure for abandonment shall be as required by the Authority Having Jurisdiction. Components of the abandoned system, including, but not limited to, pipe, tubing, fittings and valves shall not be used for potable water systems.
1623.0 Rainwater Harvesting Systems - General. All components of the system not specifically addressed by the provisions of Part III of this chapter shall meet all applicable sections of this code, and any applicable manufacturer's installation instructions.
Engineered systems shall be installed per plans and specifications of the engineer of record.
1624.0 Scope. Applications for rainwater harvesting are unique for each application. For this reason, each rainwater harvesting system proposed for use must be engineered and site-specific and are subject to the approval of the Authority Having Jurisdiction. The requirement for the system to be engineered may be waived by the Authority Having Jurisdiction.
1624.1 Water Uses. Harvested rainwater uses may include water closets, urinals, hose bibbs, industrial applications, and irrigation purposes. Other uses may be allowed when first approved by the Authority Having Jurisdiction.
1625.0 Definitions. In addition to other definitions used in the Uniform Plumbing Code, the following definitions apply to rainwater harvesting systems.
1625.1 Auxiliary Supply. The piping arranged and protected from contamination to provide an alternate means of filling a cistern.
1625.2 Cistern. The central storage component of the rainwater harvesting system. Protection and maintenance of the cistern is essential for the health of the system.
1625.3 Debris Excluder. A screen or other device installed on the gutter or downspout system to prevent the accumulation of leaves, needles, or other debris in the system.
1625.4 Flat. Having a slope no greater than 1 in 50.
1625.5 Piping System. The system of pipes that conveys the harvested rainwater and distributes it to various fixtures.
1625.6 Prefiltration. A device to mechanically remove sediment and debris.
1625.7 Pump or Pressure System. The mechanical device necessary to distribute the harvested rainwater from the cistern to the designated fixtures.
1625.8 Rainwater Harvesting System (RWS). A cistern(s), pipe, fittings, pumps and other plumbing appurtenances required for and/or used to harvest and distribute rainwater.
1625.9 Return Elbow. A section of pipe with a 180-degree bend.
1625.10 Roof Drainage System. The roof drains, overflow drains, scuppers, gutters and downspouts used to convey the rainwater from the roof surface to the system.
1625.11 Roof Surface. The surface rainwater harvesting systems rely on for the collection of rainwater that has fallen on a building roof.
1625.12 Roof Wash or Roof Washer. A device or method for removal of sediment and debris from collected roof water by diverting initial rainfall from entry into the cistern(s).
1625.13 Screen. Corrosion resistant wire or other approved mesh having openings in determined sizes.
1625.14 Slope or Sloping. Having a slope greater than 1 in 50.
1625.15 Transfer Pump. The mechanical device to transfer collected water from downspouts to remote cistern(s).
1626.0 Permit. It shall be unlawful for any person to construct, install, alter, or cause to be constructed, installed, or altered any rainwater harvesting system within a building or on a premises without first obtaining a permit to do such work from the Authority Having Jurisdiction.
In addition to the permits required by this Code, the following additional permits may be required for the installation of a rainwater harvesting system: An electrical permit for the pump or other electrical controls; a building permit for cistern footings, foundations, enclosures and roof structures; a grading permit may be necessary for underground tanks. In addition, contact your regional office of the department of ecology regarding a registration form.
1626.1 Application. The following information must be provided with each permit application for a rainwater harvesting system:
1. Site or plot plan, including site elevations.
2. A diagram of the rainwater harvesting system (including piping and equipment) and domestic potable water systems, including sizing and dimensions.
3. Specifications and manufacturer's installation instructions for cistern(s), pump(s), filtration and/or disinfection, and roof washing or pre-filtration system(s).
4. Engineering. Installation, including, but not limited to, the following systems, will require structural engineering: Cisterns that are located on top of a building structure or cisterns that are located on sloping sites.
Information in addition to that listed above may be necessary in some instances. The size and complexity of the building, site and system will determine the necessity for additional information.
1627.0 General Provisions. A rainwater harvesting system begins at the point of collection and terminates as waste after the water collected has been used in plumbing fixtures, industrial applications, or used for irrigation purposes. The parts of the collection and distribution system include the roof surface, gutters and downspouts, roof washer, cistern, pump and the piping system.
1627.1 Collection System. Rainwater shall only be harvested from roof surfaces. Harvest shall not occur from the following locations:
1. Any vehicular or pedestrian area;
2. Surface water runoff; or
3. Bodies of standing water.
1627.2 Collection Pretreatment. Rainwater harvested from roof surfaces shall be pretreated by either a roof washing system or other filtration system of no more than 50 microns. The quantity of the first flush generated by the rainwater harvesting system during any rain event shall be calculated as the first 0.02 inch of rainfall per 24-hour period per square foot of roof area and shall be diverted away from the cistern. Discharge of any diverted water shall go to a location approved by the Administrative Authority.
|EXCEPTIONS:||1. A first flush is not required where a post storage filtration or treatment system is installed and approved by the Administrative Authority.|
|2. A first flush is not required for systems used exclusively for irrigation purposes.|
1628.1 Roof Surface. The roof surface may be constructed of any material accepted by the Administrative Authority.
|EXCEPTION:||Copper, zinc or lead roofing materials shall not be used.|
1. Gutters and downspouts may be manufactured of any material. Gutter and downspout materials are not required to meet material specifications found in the Uniform Plumbing Code.
|EXCEPTION:||Copper or zinc gutters and downspouts shall not be used. If existing gutters and downspouts are already in place, the interior shall be coated with a NSF-quality epoxy paint.|
1628.3 Roof Washers and Prefiltration. All rainwater harvesting systems using impervious roof surfaces shall have at least one roof washer per downspout or prefiltration system. A roof washer or prefiltration system is not required for pervious roof surfaces such as green roofs. Roof washers and prefiltration systems shall meet the following design requirements.
1628.3.1 All collected rainwater shall pass through a roof washer or prefiltration system before the water enters the cistern(s).
1628.3.2 If more than one cistern is used, a roof washer or prefiltration system shall be provided for each cistern.
|EXCEPTION:||Where a series of cisterns are interconnected to supply water to a single system.|
1618.104.22.168 The inlet to the roof washer shall be provided with a debris screen that protects the roof washer from the intrusion of waste and vermin.
1622.214.171.124 The roof washer shall rely on manually operated valves or other devices to do the diversion.
16126.96.36.199 Roof washers shall be readily accessible for regular maintenance.
1628.3.4 Prefiltration screens or filters shall be maintained consistent with manufacturer's specifications.
1628.4 Cisterns. The following are the minimum requirements for cisterns.
16188.8.131.52 All cisterns shall be listed for use with potable water.
16184.108.40.206 Cisterns shall be capable of being filled from both the rainwater harvesting system and the public or private water system.
16220.127.116.11 The municipal or on-site well water system shall be protected from cross-contamination in accordance with Section 603.4.5.
1618.104.22.168 Backflow assemblies shall be maintained and tested in accordance with Section 603.3.3.
1622.214.171.124 Cisterns may be used as storm water collection points that help to minimize flood damage, while providing a reservoir for later use.
16126.96.36.199 Cisterns shall have access to allow inspection and cleaning.
1628.4.2 Size. Any cistern, or combination of cisterns used, shall be sized adequately for the intended use of the water.
16188.8.131.52 For above grade cisterns, the ratio of the cistern size shall not be greater than 1:1 height to width, provided that for an engineered tank with an engineered foundation, the height may exceed the width, subject to approval of the Authority Having Jurisdiction. The ratio for below grade cisterns is not limited.
1628.4.3 Location. Cisterns may be installed either above or below grade. All cisterns shall be installed in accordance with the manufacturer's installation instructions. Where the installation requires a foundation, the foundation shall be flat and shall be capable of supporting the cistern weight when the cistern is full.
16184.108.40.206 Below Grade Cisterns. Below grade cisterns shall be provided with manhole risers a minimum of 8 inches above surrounding grade. Underground cisterns shall have tiedowns per manufacturer's specifications, or the excavated site must have a daylight drain or some other drainage mechanism to prevent floating of the cistern resulting from elevated groundwater levels.
1628.4.4 Protection. Cisterns shall be protected from sunlight to inhibit algae growth and ensure life expectancy of tank.
1628.4.5 Inlets, Outlets and Openings. All cistern openings shall be protected from unintentional entry by humans or vermin. Manhole covers shall be provided and shall be secured to prevent tampering. Where an opening is provided that could allow the entry of personnel, the opening shall be marked, "DANGER - CONFINED SPACE."
Cistern outlets shall be located at least 4 inches above the bottom of the cistern.
1628.4.6 Overflow. The cistern shall be equipped with an overflow device.
16220.127.116.11 The overflow device shall consist of a pipe equal to or greater than the cistern inlet and a minimum of 4 inches below any makeup device from other sources.
1618.104.22.168 The overflow outlet shall be protected with a screen having openings no greater than 0.25 inches or a self-sealing cover.
1622.214.171.124 The Authority Having Jurisdiction shall approve the discharge location of the overflow water.
1628.5 Pump. Where a pump is provided in conjunction with the rainwater harvesting system, the pump shall meet the following provisions.
1628.5.1 The pump and all other pump components shall be listed and approved for use with potable water systems.
1628.5.2 The pump shall be capable of delivering a minimum of 15 psi residual pressure at the highest outlet served. Minimum pump pressure shall allow for friction and other pressure losses. Maximum pressures shall not exceed 80 psi.
1628.6.1 There shall be no direct connection of any rainwater harvesting pipe system and any domestic potable water pipe system.
1628.6.2 Materials. Pipe used to convey harvested rainwater shall be identified per Section 601.2 and Table 6-1. Fittings and other system components shall be listed for use in conjunction with specified piping. Both piping and fittings shall be installed as required by applicable code and standards.
16126.96.36.199 All other products entering into the construction of a rainwater harvesting system shall be listed as required by code for the purpose intended, and suitable for use in a potable water system.
1628.6.3 Color and Information. All rainwater pipe shall ((
marked)) have a purple background with black uppercase
lettering, with the words "CAUTION: NONPOTABLE RAINWATER, DO NOT
DRINK" every (( four)) twenty feet along its length, but in no
case less than once per room(( . The pipe and lettering shall
comply with Section 601.2)), and shall be visible from the
floor level. The minimum size of the letters and the length
of the color field shall conform to Table 6-1. Where
concealed within construction, the piping shall be labeled on
two opposing sides of the pipe within each stud or joist bay.
All mechanical equipment that is appurtenant to the nonpotable
rainwater system shall be painted purple.
1629.1 Commercial, Industrial and Institutional Room Entrance Signs. In commercial, industrial, and institutional occupancies, all rooms using nonpotable reuse water for water closets and/or urinals shall be identified with signs. Each sign shall contain one-half inch (12.7 mm) letters of a highly visible color on a contrasting background. The location of the sign(s) shall be such that the sign(s) shall be visible to all users. The number and location of the signs shall be approved by the Authority Having Jurisdiction and shall contain the following text:
|TO CONSERVE WATER,
THIS BUILDING USES RAINWATER TO FLUSH TOILETS AND URINALS.
NONPOTABLE RAINWATER, DO NOT DRINK.
DO NOT CONNECT TO DRINKING WATER SYSTEM.
CONTACT BUILDING MANAGEMENT
BEFORE PERFORMING ANY WORK ON THIS WATER SYSTEM.
1629.3 Every water closet or urinal supply, hose bibb or irrigation outlet shall be permanently identified with an indelibly marked placard stating:
NONPOTABLE RAINWATER, DO NOT DRINK
(A) Rainwater harvesting systems shall be inspected and tested as outlined in this code for testing of potable water piping.
(B) An initial inspection and test shall be performed on both the potable and rainwater harvesting systems. The potable and rainwater system shall be isolated from each other and independently inspected and tested to ensure there is no cross-connection.
1631.0 System Maintenance. Rainwater harvesting systems shall be maintained in functioning order for the life of the system. It is the property owner's responsibility to maintain the system until the system is abandoned as prescribed in this code.
1632.0 System Abandonment. If the owner of a rainwater harvesting system elects to cease use of, or fails to properly maintain such system, they shall abandon the system. To abandon the system one shall:
1. Remove the system entirely; and
2. Replace the rainwater harvesting pipe system with an approved potable water supply pipe system. Where an existing potable pipe system is already in place, fixtures may be reconnected to the existing system.
Rainwater harvesting system abandonment and potable water installations require permit, inspection(s) and approval(s).
[Statutory Authority: RCW 19.27.074, 19.27.031 and chapters 19.27 and 34.05 RCW. 10-03-101, § 51-56-1600, filed 1/20/10, effective 7/1/10. Statutory Authority: RCW 19.27.190, 19.27.020 and chapters 19.27 and 34.05 RCW. 07-01-094, § 51-56-1600, filed 12/19/06, effective 7/1/07.]