This article was posted on Saturday, Dec 01, 2018

California’s SB 407 (Padilla) is a water-conservation measure that was passed in 2009. The bill requires that on or before January 1, 2019, all noncompliant plumbing fixtures in multifamily residential real property and commercial real property, as defined below, be replaced with water-conserving plumbing fixtures.

AOA mentioned this in January 2018, but let this serve as reminder that if you did not replace your fixtures, you most likely will not be in code compliance on January 1st and can expect to be cited. Owners of multifamily properties with old plumbing fixtures who have not replaced them with low-flow, water efficiency improvements should do so immediately.

Below are the requirements for the new devices:

  • Toilets: They must use 1.6 gallons or less (High Efficiency Toilet – HETs)
  • Showerheads: The flow rate must be 2.5 gallons per minute or less.
  • Aerators: 2 gallons per minute or less. (A faucet aerator (or tap aerator) is often found at the tip of modern indoor water faucets. Aerators can be simply screwed onto the faucet head, creating a non-splashing stream and often delivering a mixture of water and air.)

How to Know if Your Fixtures Are Compliant Toilets:

The flush volume of a toilet simply means how much water is released when it is flushed. To qualify for this rebate program you must be replacing a toilet currently using more than 1.6 gallons per flush. So, that means you need to know your toilet’s flush volume.

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A marking or label is typically located near the toilet seat hinge on the bowl that can provide you with that information. Please note that the markings and labels are often in liters as opposed to gallons. Here’s a quick reference to help determine your toilet’s flush volume if it is listed in liters.

Gallons Per Flush                  Equals This Many Liters Per Flush

5 to 7                                       18.92 to 26.49

3.5                                           13.24

1.6 to 3.5                                 6.05 to 13.24

1.6                                           6.05

1.28                                         4.84

(Note: If your toilet has a large black cylinder inside of it instead of the standard flushing mechanism, your toilet is using 1.6 gallons per flush.)

If you cannot locate any markings or labels near the seat hinge, check the underside of the tank lid or the tank’s back inside wall for a date stamped in the porcelain.

Still can’t find any markings or labels? You can perform an easy test to determine how much water your toilet uses by following these simple steps.

  1. Turn the water supply to your toilet off. (Note: if you cannot turn the valve or do not have access to the valve simply prevent the toilet from refilling by holding up the float device in your tank.
  2. Measure the length of the tank in inches.
  3. Measure the width of the tank in inches.
  4. Measure the full water level in the toilet tank in inches (depth 1).
  5. Flush the toilet and measure the drop at the lowest level (depth 2).
  6. Subtract depth 2 from depth 1. This will give you the “drop” measurement.
  7. Multiply the length times the width times the “drop” measurement number you noted for Step No. 6 to determine the volume of cubic inches of water used per flush.
  8. Divide the volume by 231 to get the number of gallons per flush.

Here’s an example to use to help you calculate your gallons per flush.

Step 2 – Length: 17.5

Step 3 – Width: 7

Step 4 – Full level: 6

Step 5 – Low level: 3.5

Step 6 – 6 minus 3.5 = 2.5

Step 7 – 17.5 x 7 x 2.5 = 306.25

Step 8 – 306.25 divided by 231 = 1.32

Showerheads and Aerators

With showerheads and aerators, the flow rate is sometimes listed on the devices themselves. If not, you’ll need a few basic supplies for measuring the flow rate of a faucet or showerhead:

  • Container for catching water
  • Timer or stopwatch
  • Measuring cup

A small pitcher is an ideal container for faucets because it makes it easy to pour out the water for measuring. A large bucket is best for a showerhead because you want to catch all of the water from the showerhead’s spray. For a stopwatch, most people these days use a smartphone, or you can go old-school and use a watch or clock. Follow these steps to measure the flow rate:

  1. Set the timer to 10 seconds.
  2. Turn on the cold water full-blast.
  3. Start the timer and simultaneously place the container under the water stream or spray, making sure all of the water is collected.
  4. Collect the water for exactly 10 seconds and then shut off the fixture.
  5. Measure the quantity of water in the container, using the measuring cup. You might want to note the cupfuls on a piece of paper, so you don’t lose track.
  6. Convert the measurement to gallons. For example, if you measure 2 quarts of water in your container, you have collected 1/2 gallon.
  7. Multiply the measured quantity of water by 6 to calculate the flow rate in gallons per minute. In our example, 1/2 gallon multiplied by 6 equals 3 gallons. Therefore, the flow rate is 3 GPM.

(NOTE:  If you’re like me, you could find this can be unexcitable, extra work.  Call one of AOA’s many advertisers to help you through this process!)


Several water and gas utility programs offer rebates that can offset some of the cost of this work. Check with your local gas, water and power companies to apply for online rebates.

 Patricia Harris is the Senior Editor of AOA’s News and Buyer’s Guide.