Answers and Analysis
This knowledge base, updated to include the analyses from the 2003 through the most recent editions of the Uniform Plumbing and Mechanical Codes, continues to be a premier source for engineers, inspectors, students, contractors and tradesmen. Questions come from a broad base of users, and answers are informal interpretations of the Codes provided by a committee of code officials and special experts - they are clearly stated and to the point. This updated site combines the most pertinent analyses from the previous manual and presents them together with those based on the most recent publications of the Uniform Codes. This makes the Answers and Analysis database one of the most valuable tools you as a member can access wherever you have an internet connection.
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Questions matching UPC Chapter 16
7 results
UPC 2009 1613.0, 602.0, 603.0, 603.4.5
UPC 2012 1603.4
Topic: Connections
1. Can a Reduced Pressure Principle Backflow Preventer Assembly be used to separate reclaimed water from potable water? 2. Can a Reduced Pressure Principle Backflow Preventer Assembly be used for protection to refill the
reclaimed water systems tank in times when the tank is not receiving water from rainfall?
3. Is an air gap the only way to prevent cross connection from occurring when refilling the holding tank
for reclaimed water?
reclaimed water systems tank in times when the tank is not receiving water from rainfall?
3. Is an air gap the only way to prevent cross connection from occurring when refilling the holding tank
for reclaimed water?
1. Yes, Section 1613.0(A) of the 2009 UPC addresses the use of potable water as make-up water for reclaimed water systems. That section states, “…Potable water supplied as makeup water in these
systems shall be protected against back-pressure and back-siphonage to accordance with Section
602.0 and 603.0.” Section 602.2 requires the installation of a “backflow prevention device approved for
the potential hazard” when connecting potable water systems to piping carrying water that has been
used for other uses.
2. Yes (see first answer).
3. No, though an airgap is the optimum type of protection for a high hazard installation such as this, other
devices designed for maximum protection of the potable water system may be used.
Note: Section 1603.4 (2012) requires an airgap or reduced pressure backflow preventer where potable water is used for makeup water for the reclaimed water system.
systems shall be protected against back-pressure and back-siphonage to accordance with Section
602.0 and 603.0.” Section 602.2 requires the installation of a “backflow prevention device approved for
the potential hazard” when connecting potable water systems to piping carrying water that has been
used for other uses.
2. Yes (see first answer).
3. No, though an airgap is the optimum type of protection for a high hazard installation such as this, other
devices designed for maximum protection of the potable water system may be used.
Note: Section 1603.4 (2012) requires an airgap or reduced pressure backflow preventer where potable water is used for makeup water for the reclaimed water system.
UPC 2012 1601.5
Topic: Maintenance and Inspection
Section 1601.5 of the 2012 UPC outlines the maintenance requirements for Alternate Water Sources and references Table 1601.5. This Table requires an annual cross-connection test with a footnote of "the cross-connection test shall be performed in the presence of the Authority Having Jurisdiction in accordance with the requirements of this chapter". Is it the intent to require all types of alternate water sources to have a cross-connection test performed or does it depend on the type of alternate water source installed as to whether or not a cross-connection test is required? Does a gray water system installed in accordance with section 1602.0 require a cross-connection inspection and test per Table 1601.5?
Comment
Section 1602.0 Gray Water does not mention a cross-connection test. Section 1603.0 Reclaimed Water requires a cross-connection test. Section 1604.0 On-Site treated nonpotable water requires a cross-connection test. Chapter 17 requires a cross-connection test if a portion of the system is installed within a building. Table 1601.5 footnote states "...in accordance with the requirements of this chapter" which means only when specifically required within the chapter.
Comment
Section 1602.0 Gray Water does not mention a cross-connection test. Section 1603.0 Reclaimed Water requires a cross-connection test. Section 1604.0 On-Site treated nonpotable water requires a cross-connection test. Chapter 17 requires a cross-connection test if a portion of the system is installed within a building. Table 1601.5 footnote states "...in accordance with the requirements of this chapter" which means only when specifically required within the chapter.
No, Sections 1603.11 and 1702.11 of the 2012 UPC specifically addresses inspection and testing of reclaimed (recycled) water systems and non-potable rainwater catchment systems respectively. These types of alternate water sources are normally pressurized and supply treated water or rain water to water closets, urinals, trap primers and aboveground or subsurface irrigation, oftentimes via piping material that may also be used for potable water systems. For this reason, both reclaimed (recycled) and non-potable rain water systems shall be tested initially and annually for possible cross-connections between potable and non-potable water systems.
Additionally the pipe must be marked as “non-potable” per Section 601.2 and warning signs posted on all fixtures that receive water from these systems (see Section 1603.10 and 1702.10).
Gray water by definition is untreated waste that as not come in contact with toilet waste, kitchen sink or dishwasher waste and may only be used for subsurface irrigation. These systems are piped in waste water piping, not water supply piping, and cannot be used to supply water to toilets or urinals. If Gray water is collected and treated and is suitable for direct beneficial use in the building it is no longer Gray water and would now be defined as on-site treated nonpotable water, which would be required to have cross connection test per section 1604.0.
Additionally the pipe must be marked as “non-potable” per Section 601.2 and warning signs posted on all fixtures that receive water from these systems (see Section 1603.10 and 1702.10).
Gray water by definition is untreated waste that as not come in contact with toilet waste, kitchen sink or dishwasher waste and may only be used for subsurface irrigation. These systems are piped in waste water piping, not water supply piping, and cannot be used to supply water to toilets or urinals. If Gray water is collected and treated and is suitable for direct beneficial use in the building it is no longer Gray water and would now be defined as on-site treated nonpotable water, which would be required to have cross connection test per section 1604.0.
UPC 2009 1602.0
UPC 2012 1602.0
UPC 2015 1502.0
Topic: Gray Water Systems
What are the codes and regulations relating to the use of kitchen-generated gray water?
The provisions for the installation of Gray Water Systems are found in Chapter 15 (2015), Chapter 16 (2009/2012) Alternate Water Sources For Non Potable Applications. Kitchen sink waste is not allowed in a Gray Water System.
The definition of Gray Water in Chapter 2 Definitions is untreated wastewater that has not come into contact with toilet waste, kitchen sink waste, dishwater waste or similarly contaminated sources. Gray water includes wastewater from bathtubs, showers, lavatories, cloth washers and laundry tubs.
The definition of Gray Water in Chapter 2 Definitions is untreated wastewater that has not come into contact with toilet waste, kitchen sink waste, dishwater waste or similarly contaminated sources. Gray water includes wastewater from bathtubs, showers, lavatories, cloth washers and laundry tubs.
UPC 2012 1702.1
UPC 2015 1601.1
Topic: Rainwater Catchment Systems
Where in the UPC is the specific code that prohibits untreated rainwater from being introduced into a building?
The UPC allows non-potable water to be used in some applications. Chapter 17 (2012), Chapter 16 (2015) regulates non-potable rainwater catchment systems. The installation of rainwater catchments systems is only intended to supply uses such as water closets, urinals, trap primers for floor drains and floor sinks, irrigation, industrial processes, water features, cooling tower makeup and other uses shall be approved by the Authority Having Jurisdiction.
Appendix K if adopted would allow the rainwater to be treated to potable standards and be used for drinking purposes.
Appendix K if adopted would allow the rainwater to be treated to potable standards and be used for drinking purposes.
UPC 2009 1601.0, 1610.2
UPC 2012 601.2.2.1 (1), 1602.0, 1602.9.3
UPC 2015 601.3.3, 1502.0, 1502.9.3
UPC 2018 601.3.3, 1501.7, 1503.0
Topic: Alternate Water Sources
1. Does all buried piping and drip tubing need to be purple color or can it optionally be marked with purple tape indicating "Reclaimed Water-Do Not Drink"?
2. Is there any restriction on the use of pop-up spray heads for plant irrigation using recycled water? (Pop-up sprays as opposed to a full drip system.)
3. Is there any restriction on the use of pop-up spray heads for plant irrigation using gray water? (Pop-up sprays as opposed to a full drip system.)
Comment:
For the installation of a planting irrigation system using gray or recycled water for the roof terrace of a commercial building, which will also be a usable space for tenants.
2. Is there any restriction on the use of pop-up spray heads for plant irrigation using recycled water? (Pop-up sprays as opposed to a full drip system.)
3. Is there any restriction on the use of pop-up spray heads for plant irrigation using gray water? (Pop-up sprays as opposed to a full drip system.)
Comment:
For the installation of a planting irrigation system using gray or recycled water for the roof terrace of a commercial building, which will also be a usable space for tenants.
1. No. Per Section 1503.9.3 of the 2018 Uniform Plumbing Code, there are no special requirements for marking of grey water subsoil irrigation field pipe and fittings. Sections 1504.8 and 1505.7 does refer the installer to Section 601.3 for marking information for gray water and treated reclaimed water systems.
2. Yes. Section 1501.7 requires grey or reclaimed water to “meet the applicable water quality requirements for the intended application as determined by the Authority Having Jurisdiction”. Grey water used for subsurface irrigation is not required to be treated.
3. Yes. Per Section 1501.7 only water that is treated to applicable water quality requirements may be used above grade. Grey water used for subsurface irrigation is not required to be treated.
2. Yes. Section 1501.7 requires grey or reclaimed water to “meet the applicable water quality requirements for the intended application as determined by the Authority Having Jurisdiction”. Grey water used for subsurface irrigation is not required to be treated.
3. Yes. Per Section 1501.7 only water that is treated to applicable water quality requirements may be used above grade. Grey water used for subsurface irrigation is not required to be treated.
UPC 2015 1609.3.1, 1505.10.2
Topic: Surface Water Runoff
1. Is the reuse of natural precipitation runoff discharging into a pond (1602.9.3.1)and used for fountains and waterfalls (which create aerosolized sprays) required to be disinfected according to Section 1504.10.2 UPC 2015?
Yes. Per Table 1602.9.4 of the 2015 Uniform Plumbing Code, rainwater used for ornamental fountains and other water features shall be first pumped to a storage tank that is equipped with a debris excluder as required in Section 1602.9.10 and then purified to remove Escherichia coli (<100CFU/100ml) and Turbidity (<10NTU).
UPC 2015 1602.9.3.1, 1505.10.2
Topic: Surface Water Runoff
1. Is the reuse of natural precipitation runoff discharging into a pond (1602.9.3.1)and used for fountains and waterfalls (which create aerosolized sprays) required to be disinfected according to Section 1504.10.2 UPC 2015?
Yes. Per Table 1602.9.4 of the 2015 Uniform Plumbing Code, rainwater used for ornamental fountains and other water features shall be first pumped to a storage tank that is equipped with a debris excluder as required in Section 1602.9.10 and then purified to remove Escherichia coli (<100CFU/100ml) and Turbidity (<10NTU).