Water Use Inventory
Part I – Reading a Water Bill
To complete this part of the activity, you must get a copy of your water bill. Ask your parents to visit this link for the city of
Turlock to get the bill online if they don’t have a hard copy.
https://ci.turlock.ca.us/citydepartments/administrativeservices/financedivision/utilitybilling/
If you cannot get a copy of your water bill, you may do the calculations based on the water bill of one of your classmates. If you
use a classmate’s bill, you must determine proportionally how much water is used by your household versus your classmate’s
household. For example, if you use the bill of a classmate with five members of their household and you have three members of
your household, you should use 60% of the amounts on their bill (if the household sizes were reversed, you would use 167%
of the amounts on their bill)
1) Determine the number of days covered by the bill: _______ days
2) On the bill, find the total amount being charged for water (do not include any late charges): $_______
The city of Turlock meters water and bills customers by the gallon.
3) Calculate the average cost of water to your household. (use this result in Part III)
Use the entire “WATER CHARGES” cost and not just the Commodity Charge total cost per gallon: _______ $/gallon
4) Determine the total volume of water used by your household in gallons for the time period of the bill: _______ gallons
5) Determine the average volume of water in gallons used per person for the time period of the bill: _______ gallons/person
6) Determine the average volume of water in gallons used per day by your household: _______ gallons/day
7) Determine the average volume of water in gallons used per person per day: _______ gallons/person/day
How We Pay for Water in Turlock in 2015
 Capacity Charge: $20.00
(This is to maintain pipes, wells, pumps,
water quality, etc.) Everyone pays this much
no matter how much they use.
 Customer Charge: $2.50
Pays for metering and billing
 Commodity Charge: $0.57 per 1000 gallons
Cost per gallon of water.
Part II – Estimated Water Use
The figures in the “Estimated Volume of Water Used” column are estimates. There is much variation in these values from home
to home. For example, if you have a water-efficient showerhead the water flow will be about half the amount for a standard
showerhead. If you have a water-efficient toilet the water used per flush will be as low as 1.3 gallons per flush. The amount of
water used for tooth brushing, shaving, hand and face washing, and dishwashing will vary significantly based on the time
spent and the faucet setting. The amount of water used in the yard will vary depending on the area in need of water and the
frequency of watering.
Determine the actual amount of water used by your household. Some appliances (toilets, washing machine, and dishwashers
for example) will have a label stating the amount of water used per flush or use. You may also use a pitcher or bucket to
estimate the rate that water flows from a faucet, showerhead, or hose. After collecting water and measuring its volume,
don’t waste the water – use it water for watering plants in or around your house.
Use
Shower
Fill bathtub
Toilet Flushing
Approximate Volume of Water Used
2-10 gal/min
30-50 gal/use
1.5-5 gal/flush
Tooth brushing
Washing hands and face
Shaving
Cooking
Clothes Washing Machine
Dish Washing by hand
1-5 gal/min
1-3 gal/min
1-5 gal/min
1-10 gal/meal
20-50 gal/use (depending of setting)
5-40 gal/occurrence
Dish Washing
Watering the Yard
Lawn Sprinklers
Washing Car
Wash down driveway w/hose
Replace evaporation from swimming pool
15-30 gal/use (depending on setting)
10-20 gal/min
5-20 gal/min
10-20 gal/min
10-20 gal/min
Varies widely
effective date >
fiscal year >
Commodity Charge, $ per 1000 gallons
System Average
Single/Multi Residential
Commercial/Industrial/Institutional
Landscape
Service Charge, $ per meter per month
1" or less
1.1/2"
2"
3"
4"
6"
8"
10"
Customer Charge, $ per account per
month
7/1/2014
FY15
1/1/2015
FY15
1/1/2016
FY16
1/1/2017
FY17
$0.45
$0.48
$0.37
$0.51
$0.53
$0.57
$0.43
$0.60
$0.58
$0.63
$0.46
$0.65
$17.50
$35.00
$56.00
$123.00
$210.00
$438.00
$840.00
$1,330.00
$20.00
$40.00
$64.00
$140.00
$240.00
$500.00
$960.00
$1,520.00
$2.20
$2.50
Estimated Volume of Water Used
1/1/2018
FY18
1/1/2019
FY19
$0.68
$0.74
$0.54
$0.75
$0.77
$0.84
$0.60
$0.84
$0.86
$0.94
$0.67
$0.94
$21.20
$42.40
$67.90
$149.00
$255.00
$530.00
$1,018.00
$1,612.00
$24.10
$48.20
$77.20
$169.00
$290.00
$603.00
$1,157.00
$1,832.00
$26.50
$53.00
$84.80
$186.00
$318.00
$663.00
$1,272.00
$2,014.00
$29.40
$58.80
$94.10
$206.00
$353.00
$735.00
$1,412.00
$2,235.00
$2.60
$3.00
$3.30
$3.60
Part III – Personal Water-Use Inventory
For shared activities like washing clothes, cooking, watering the yard, etc., calculate your share of the water used. For example,
if there are 4 people in your household and the washing machine is estimated to use 40 gallons per load, your share is 40/4 =
10 gallons. For activities that are not applicable to your family (watering the yard, if you live in an apartment; swimming pool
evaporation, if you have no pool, etc.) write “NA” in the boxes for that activity.
Use the data from your estimates in Part II to fill in the “Estimated Volume of Water Used” (third column).
Use the appropriate calculation in Part I to fill in the “Cost of Water per Gallon” (sixth column).
Time (in
minutes) or
Number of Uses
per Day
Use
Estimated Volume
of Water Used
(from Part II
including units)
Estimated
Volume of Water
Used per day
(gallons)
Cost of Water
per Gallon
(from
Part I)
Estimated
Cost of
Water
per day
Estimated
Cost of
Water
per year
Shower
Fill Bathtub
Flush Toilets
Brush Teeth
Wash hands and/or face
Shave
Cook
Wash Clothes
Wash Dishes
Water Yard
Use Lawn Sprinklers
Wash Cars
Wash driveway
Fill Swimming Pool
Other:
Other:
Totals
N/A
Part IV – Questions
1) How do the results of your calculations in Part I compare to the totals in Part III?
2) How could the Personal Water-Use Inventory (Part III) have more accurately estimated the actual amount of water used
by you and your family?
3) If you did not use your own water bill check here: ____ and respond to the following: Explain why proportionally adjusting
a classmate’s bill to determine your household water consumption is not an accurate way of estimating your water use
and costs.