Do-It-Yourself Residential Customer Water Audit
Your water meter
This guide will assist you in understanding your water meter, checking for leaks that can waste water and cost you money, estimating your household’s current water use, and making adjustments to your water use. As you read the information provided in this guide, print and use the Meter Read Log to record your water use. You should be able to estimate daily water use and water use for the month.
Your meter can tell you how much water you are using per day, week, month and year. You can monitor your meter yourself and check your figures against our figures to verify the accuracy of your water bill. Your meter can also show leaks in your water system.
Your water meter is inside a rectangular concrete or plastic box, flush with the ground, and is usually located near a roadway curb or sidewalk near the residence’s property line. Be careful when opening the lid as there may be spiders, snakes, bees or bugs inside.
Do you have a leak?
To test for leaks in your plumbing system, turn off all indoor and outdoor water use activity (sinks, dishwasher, sprinklers, etc.). Lift the lid from the meter and look for a small red diamond- or triangle-shaped dial or a silver-colored disk on the meter face. If this is turning, you have a leak. To estimate the severity of the leak, record the numbers on the water meter register, which looks like an odometer. Wait two to four hours (overnight if possible), then reread your meter. The meter registers in cubic feet: 1 cubic foot equals 7.48 gallons; 100 cubic feet equals 748 gallons or 1 billing unit.
Turn off the house gate valve to determine if the leak is outside your home. The gate valve is usually located at a hose bib on an outside wall, generally in a direct line from the water meter. If the meter dial still moves, you should investigate the possibility of a leak in the line between the meter and the house.
Leaks in your irrigation system won’t always show on your meter due to their separate anti-siphon shutoff valves. To find leaks, walk your irrigation lines. Check for unusual wet spots, leaky or broken sprinkler heads, and use your meter to measure total irrigation use. Locate all hose bibs and check for leaks and drips. Replace washers if there are any leaks.
Check toilets for leaks. Put a few drops of food coloring or other dark-colored liquid in the tank. Don’t flush. Wait 10 minutes. If color appears in the bowl, there is a leak in the toilet mechanism.
Pool and Pool Equipment Leaks
Your pool will naturally lose some water to evaporation and splash-out. You may also gain water from rainfall. A rule of thumb is that if you’re routinely adding more than two inches of water to your pool per week, you may have a leak. It is worth spending some time and money to repair.
Pools are meant to be watertight but sealants will deteriorate while other parts of your pool shift and settle or just plain wear out. Pools can leak through any of the fittings or accessories, plumbing, or even right through the shell. It is important to repair leaks, not only to save water, heat, and chemicals, but also to prevent undermining a pool’s structural components and washing away fill dirt.
Look closely at the filter, pump, heater, and pool fill valve(s). Check the ground for moisture. Turn the pump on and off, looking closely for spraying water when the pump is turned off.
Take a walk around the pool’s edge and between the pool and the equipment pad. Check for wet soil and eroded areas.
If so, there are special considerations. Look for sinkholes where sand under the liner may have washed away. If an animal has fallen into your pool you may notice claw (tears) marks just below the water line. Spending time under water with a mask may be required to find a small leak in the liner. When the liner becomes old they may have small pinhole leaks.
Place a bucket of water beside the pool and mark both the water in the bucket and the pool water level. Wait 24 hours, then check the loss of both. If the pool loses more water than the bucket, then you have a leak.
Water Use Outside the House
This section will help you to determine how much water you are using and show you ways to cut back on your water use.
Measure garden hose output by writing down the time needed to fill a 1- or 2-gallon bucket. Calculate the amount of water used in one minute.
* A typical 5/8” garden hose can use 12 to 15 gallons a minute.
Perform a timed consumption test for your irrigation system.
- Turn off all water use in the house.
- Record the reading on the water meter.
- Turn on the sprinklers for the usual water schedule.
- When the sprinklers shut off, read the meter again.
- Determine how much water is used each time you irrigate.
- Use this number in the Calculating Weekly Water Use section below.
Perform a catch-can test.
- Set out three empty tuna fish cans or similar straight-sided cans within the boundaries of a sprinkler station.
- Turn on the system for fifteen minutes.
- Measure the depth of the water in each can with a ruler and take the average depth.
- If you measured 1/4 inch as the average, this would mean that your sprinkler system puts out 1 inch an hour.
Check the accuracy of the irrigation system controller by comparing the watering times of each station to the actual time shown on the controller. Look at all sprinkler heads and check for operating efficiency. Consider replacing nonefficient sprinkler heads with newer conserving models. Over-spray can increase your needed watering time. Check for over-spray onto paved surfaces and reposition the sprinkler head to make sure any over-spray is avoided.
Water Use Inside your Home
Aerators can reduce water flow in half. Aerators can be purchased at your local hardware store. You can also reduce pressure and flow by turning down the valve under the sink that supplies water to the faucet.
Analyze faucets in the kitchen sink and bathroom sink
Put a 1-gallon jug under a faucet and turn on to the normal flow and write down how long it takes to fill completely.
Put a 1-gallon or larger bucket under the showerhead and turn on the water full blast. Check number of seconds it takes to fill the bucket. Calculate how many gallons flow out in one minute (gallons per minute, GPM). If the showerhead output is more than 3 GPM, replace the showerhead with a water-conserving model of 3 GPM or less. You may also check the meter before and after running the shower for five minutes to determine the volume of water used within the five-minute test.
Check the tank size. The size may be stamped on the inside walls on the tank or lid. If the size is not marked on the toilet, turn off handle to shutoff valve located on the wall behind the tank. Flush the toilet. The tank should be empty. Use a 1-gallon bucket to refill the tank to its normal level. If you need more than 3 gallons of water to fill the tank, consider replacing the toilet with a more efficient model using 1.6 gallons or less.
Calculating weekly water use
Take the water use calculation from your timed consumption test. Multiply this by the number of times your sprinkler system is operating during a seven-day period to determine your total weekly irrigation use.
Amount of water used during one sprinkler cycle _____________
x number of times sprinklers run per week _____________
= my total weekly irrigation use ____________
Indoor and miscellaneous water use
Print the Household Indoor Water Use Calculation worksheet to help determine your total weekly indoor and other water use. After completing the worksheet, multiply the total daily indoor water use by 7 to estimate weekly indoor water use.
My total daily water use indoors ____________
x 7 days = my weekly indoor water use _____________
Add the weekly irrigation use total and the weekly indoor totals together to estimate your total weekly water use.
Weekly irrigation use ______
+ weekly indoor water use ______
= Total weekly water use ______