Dual Plumbed Systems and Cross Connection Control (California Department of Public Health)
CDPHCalifornia Department of Public Health Dual Plumbed Systems and Cross Connection Control Nov 9, 2010
Dual Plumbed Systems Presented by Randy Barnard Drinking Water Program California Department of Public Health
CDPH, Drinking Water Program Besides regulating public drinking water systems, CDPH: Established Water Recycling Criteria (Title 22) which outline treatment and reuse requirements Established Cross-Connection Control Regulations (Title 17) to protect public water supplies On-going involvement with cross-connection control issues Reviews new and emerging treatment technologies Collects fees from project applicants
What is Recycled Water Water which, as a result of treatment of waste, is suitable for direct beneficial use. (Direct beneficial use means the use of RW that has been transported from the point of treatment or production to the point of use without an intervening discharge to waters of the State.) Mostly municipal wastewater.
Types of Recycled Water Secondary (undisinfected) Secondary-23 Secondary-2.2 Tertiary Filtered via media or membrane Disinfected-2.2 via CT criteria or Alt method Tertiary is what we will focus on!!
Uses of Recycled WaterAccording to Title 22, Section 60307 Disinfected tertiary recycled water: Flushing toilets and urinals Commercial laundries Decorative fountains Priming drain traps Industrial process water
Dual Plumbed SystemsAccording to Title 22, Section 60301.250 Means a system with separate piping for recycled water and potable water within a facility. And the recycle water serves Plumbing outlets (not fire) within a building or Outdoor landscape irrigation at residences.
Not Allowed Dual Plumbed Toilet and urinal flushing in mental facilities. (Section 13554(a)) Inside facilities that produce/process food. (Section 60313(c)) Internal individually-owned residential units (except for fire). (Section 60313(b))* *Conflicts with new 2007 statue 13553
Recycled Water and CondosAccording to CA Water Code, Section 13553 (New statue not reflected in regs yet!) RW may be used in condos if Title 22 Engineering report Backflow protection of drinking water Appropriate modifications Cross connection testing Maintain records Condo declaration stating RW use
New CA Plumbing CodeCode Chapter 16 - Part II California Dual Plumbing Code established statewide standards for installing both potable and recycled water plumbing systems in commercial, retail, and office buildings, theaters, auditoriums, condominiums, schools, hotels, apartments, barracks, dormitories, jails, prisons, and reformatories. The new code will be effective January 2011.
Title 22 Engineering Report Section 60323 (general) Qualified, CA PE engineer with wastewater experience. Design description. Indicate means for compliance with regs. Contingency plan assuring only treated RW to use areas.
Title 22 Engineering Report Section 60314 (Dual plumbed specific) Details of: Number, location, and type of facilities in use area. Ave number of persons served daily. Boundaries including maps. List of operation personnel at each facility. RW use at each use area.
Title 22 Engineering Report Section 60314 (Dual plumbed specific) Plans and Specs including: Proposed piping system. Pipe locations for RW and PW. Type and location of fixtures accessible to public. Back flow prevention methods. Description of cross connection prevention methods.
Other Key Points of Dual Plumbed PW back up supply only allowed via an air- gap separation. Report back flow incidents to CDPH <24 hours.
Other Key Points of Dual Plumbed Back flow devices inspected/maintained. Cross Connection inspections (visual) Before system S/U Annually Cross Connection tests (physical) Every 4 years
Cross Connection ControlInternal Dual Plumbed Presented by Brian Bernados Drinking Water Program California Department of Public Health
•Title 17: Backflow Protection Reasons for Backflow Protection Water user’s onsite activities pose a health risk to the water supply if access is provided. Many involve Increase threat of cross-connections (dual plumbed, graywater, recycled water systems)
Backflow Prevention Usually Nothing Happens Its Big News When it Does Happen Multiple Things Go Wrong Need Water and Contaminants Something is plumbed wrong Humans Aren’t Paying Attention It Happens
Poorly Plumbed Fixtures The public had been drinking recycled water for several years from a drinking fountain before this was discovered. This was found through a pressure shutdown testing procedure.
Title 17 RegulationsPWS must install backflow protectionassemblies approved by the CDPH. (alist of approved assemblies is available)Annual testing is required of BackflowAssemblies; defective assemblies mustbe replaced or repaired with approvedparts/assemblies
What Happens Beyond the meter? Location of Backflow Protection - Generally, located as close as practicable to user’s connection (typically at the meter). Protects public distribution system Leaves the on-site system vulnerable to potential for cross-connections
Tertiary Recycled Water is Highly Treated, But Not Potable
Recycled Water SystemsCROSS-CONNECTION TESTS AREIMPORTANT!!! Tracer, Pressure or Shut-down Test Visual Inspections Plan Check/As- builts On-site Supervisor Training Signs
1620A .0 Inspection and Testing.(a) Initial cross-connection test before the initial operation system;(b) an annual visual system inspection;(c) a cross-connection test every 4 years;(d) a cross-connection test when there is material reason to believe that the potable water and/or recycled water system separation has been compromised;A material reason to believe that the system has been compromised may be based on, but is not limited to, evidence gathered: (a) during a visual inspection, or (b) as a result of an inspection performed following complaints of water quality or flow conditions consistent with a compromised system(e) a cross-connection test following remediation of a discovered cross-connection.
Annual Visual System Inspection.A visual inspection shall be conducted annually by the Authority Having Jurisdiction or other authorities having jurisdiction.(i) Recycled water & potable water meters are checked to verify that no modifications were made, and that no cross- connections are visible.(ii) Check all pumps & equipment, room signs, and exposed piping.(iii) Check all valves ensure that valve lock seals are still in place and intact. All valve control door signs shall be checked to verify that no signs have been removed.(iv) If the visual inspection indicates that the recycled water plumbing has been modified, a Cross-Connection Test is required.
“Cross-Connection Test” 1st half Potable water is activated and pressurized. Recycled water is shut down and completely depressurized. Potable remains pressurized while the recycled water system is depressurized. Time period the recycled water system is to remain depressurized is case-by-case, taking into account the size and complexity of the potable and recycled water distribution systems, (typically at least one hour). All fixtures, potable & recycled, are checked for flow. Flow from any recycled outlet indicates a cross- connection. No flow from a potable outlet indicates it is connected to the recycled water system.
“Cross-Connection Test” 2nd half Potable water is completely depressurized. Recycled water is activated and pressurized. (For the initial test, a temporary connection to potable is required to test the recycled plumbing. At the conclusion, the temporary connection is disconnected. Recycled remains pressurized while the potable is depressurized. Time period is case-by-case, (typ. at least 1 hour). All fixtures, potable & recycled, are checked for flow. Flow from any potable outlet indicates a cross- connection. No flow from a recycled outlet indicates it is connected to the potable water system.
Cross-Connection Discovered(i) Shut down recycled water piping at the meter, and the recycled water riser shall be drained.(ii) Shut down potable water to the building at the meter.(iii) The cross-connection shall be uncovered and disconnected.(iv) The building shall be retested.(v) Potable water system is chlorinated with 50 ppm 24 hours.(vi) The potable water system is flushed after 24 hours, and a standard bacteriological test shall be performed. If test results are acceptable, the potable water system may be permitted to be recharged.Notify water agency, CDPH, County DEH, RWQCB.
Authority Having Jurisdiction Test shall be conducted in the presence of the Authority Having Jurisdiction or other authorities having jurisdiction to determine whether a cross-connection occurred. Authority Having Jurisdiction = CDPH Alternate inspection and testing requirements may be allowed by the Authority Having Jurisdiction for residential, institutional or industrial buildings where shutting off the water is not practical. With CDPH approval - The recycled water purveyor or other designated appointee may substitute for the Authority Having Jurisdiction in the above mentioned inspection and tests. CDPH may delegate to the County DEH.
County of San Diego Recycled Water Plan Check and Inspection Manual Specific details of the two methods can be found in this manual. Good reference
DHS Oversight Options Public Notification if cross connection occurs Require Preparation of Plans/Reports Preferred Approaches Technical Assistance Guidance/Education Stress the Importance of Public Perception and Education – What do customers want in the water they drink???