Water Budget & Cost Estimator

Estimate your water budget and avoid surprises. 


The Water Budget & Cost Estimator below helps you easily estimate your monthly water budget and charges based on the estimated usage you provide. No login required.

Using the information on your billing statement, enter your Customer ID, input your estimated water usage, and select a calendar month to get started. Please note: Your selected calendar month may differ from your actual billing cycle. 

Learn more about how your water budget works with tiered rates at WesternWaterCA.gov/WaterBudget.

Western Water uses water budget-based tiered rates. As a Western Water customer, you receive an individualized water budget to ensure you have the water you need for every moment. Your individualized water budget is designed to meet your specific indoor and outdoor water needs for each billing period.

The calculator below may assist you in estimating how your water use impacts your monthly water bill. We recommend having your monthly water bill available when using the calculator below. You’ll need several numbers from your monthly bill to complete your calculation, such as your Account ID and estimated water usage.

Please Fill out the following fields below:
Account ID
Account ID not found in our records
Estimated HCF (Hundred cubic ft.)
Estimated HCF must be 1 or greater
Month
Enter your Account ID
Where to find your ID

Service Area: {{ accountInfo.serviceArea }}

Month
Estimated Water Budget
{{ totalWaterBudget.toFixed(2) }} HCF
Enter Acct + Month to view
Tier 1 + Tier 2 allocation
Estimated Water Usage

Tier 1 Indoor Water Budget

{{ personPerHouse || 0 }} People in Household
Auto-filled from account data
multiply
{{ gallonsPerDay }} Gallons
Per day
multiply
{{ daysInCycle ? `${daysInCycle} days` : '-'}}
Days of Usage
divide
{{ gallonsConversionFactor }} gallons
Billing Unit Conversion

Tier 2 Outdoor Water Budget

{{ landscapeArea || 0 }} sq ft Irrigated Landscape Area
Auto-filled from account data
multiply
{{ eto || '-' }}
Average Monthly Evapotranspiration (Weather Data)
multiply
{{ plantFactor || '-' }}
Landscape Efficiency Factor
multiply
{{ inchesToGallons }}
Gallon Conversion
divide
{{ gallonsConversionFactor }} gallons
Billing Unit Conversion
Calculate*RE-Calculate*Calculating...

Estimated Water Budget

TierEstimated HCF
Tier 1
Indoor Water Budget
Estimated HCF
{{ t1Estimate !== null ? t1Estimate.toFixed(2) : '-' }}
{{ t1Estimate !== null ? toUsd(t1Charge[0]) : '-' }}
{{ t1Estimate !== null ? toUsd(t1Charge[i]) : '-' }}
Tier 2
Outdoor Water Budget
Estimated HCF
{{ t2Estimate !== null ? t2Estimate.toFixed(2) : '-' }}
{{ t2Estimate !== null ? toUsd(t2Charge[0]) : '-' }}
{{ t2Estimate !== null ? toUsd(t2Charge[i]) : '-' }}
Tier 3
Inefficient Water Use
Estimated HCF
{{ t3Estimate !== null ? t3Estimate.toFixed(2) : '-' }}
{{ t3Estimate !== null ? toUsd(t3Charge[0]) : '-' }}
{{ t3Estimate !== null ? toUsd(t3Charge[i]) : '-' }}
Tier 4
Unsustainable Water Use
Estimated HCF
{{ t4Estimate !== null ? t4Estimate.toFixed(2) : '-' }}
{{ t4Estimate !== null ? toUsd(t4Charge[0]) : '-' }}
{{ t4Estimate !== null ? toUsd(t4Charge[i]) : '-' }}
Estimated Water Use Charges
Estimated HCF
{{ (t1Estimate !== null && estimatedHcf !== null) ? Number(estimatedHcf).toFixed(2) : '-' }}
{{ (t1Estimate !== null && totalCharge !== null) ? `${toUsd(totalCharge[0])}*` : '-' }}
{{ (t1Estimate !== null && totalCharge !== null) ? `${toUsd(totalCharge[i])}*` : '-' }}

Fixed and Sewer Charges

Charge Type
{{ charge.displayName || charge.chargeDescription }}
{{ charge.Year1 !== null ? toUsd(charge.Year1) : '-' }}
{{ charge['Year' + (i + 1)] !== null ? toUsd(charge['Year' + (i + 1)]) : '-' }}
Fixed and Sewer Charges Subtotal
{{ fixedSewerSubtotal !== null ? toUsd(fixedSewerSubtotal[0]) : '-' }}
{{ fixedSewerSubtotal !== null ? toUsd(fixedSewerSubtotal[i]) : '-' }}
Total Estimated Charges
{{ grandTotal !== null ? toUsd(grandTotal[0]) : '-' }}
{{ grandTotal !== null ? toUsd(grandTotal[i]) : '-' }}
*Disclaimer

The water usage and cost estimates provided by this tool are for informational purposes only. Actual usage and billing may vary based on meter readings, rate changes, fees, and other factors. Western Water does not guarantee the accuracy of these estimates and is not responsible for decisions made based on them. For official billing information, please refer to your billing statement or contact our Customer Service team at 951.571.7104 or email us.

Variable, Fixed and/or Sewer Charges

Your billing statement includes variable, fixed, and/or sewer charges. Learn more about your water bill and rate structure.

Water Estimator Vocabulary

Account ID

Your Account ID is a unique number assigned to you. It is made up of your customer number and account number. This information is printed on your billing statement.

How to find it on your bill:

For step-by-step instructions, please visit our billing guide: How to Read Your Bill
Account ID on Bill
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Water Estimator Vocabulary

Estimate Water Usage

Your Estimated Water Usage is the amount of water you expect to use for the month. To find this number, look at a past water bill:
  • On your bill, usage is shown in HCF (Hundred Cubic Feet) on your bill under the Detail of Current Charges & Adjustments section.
  • Use the "Usage" number from a past month that's similar in season or weather as you are estimating.
  • Example: If your bill shows 16 HCF, enter 16 "Estimated Water Usage".
Tip:
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Water Estimator Vocabulary

Month

Choose the month for which you would like to see your estimated water budget. The estimated water budget can then be compared against the actual water use shown in the My Western Water Portal.

Note: Billing statements are issued on billing cycles and do not directly align with the opening and closing of each month.
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Water Estimator Vocabulary

Days of Usage

The number of days in the selected month.
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Water Estimator Vocabulary

Estimated Water Budget

Western Water's customers receive a personalized water budget. The total water budget includes a customer's indoor water budget (Tier 1) and outdoor water budget (Tier 2). The number of billing units in your total water budget varies each billing period depending on the number of days within the billing cycle and local weather information. Therefore, customers may receive a higher water budget during longer billing cycles and also in the warmer summer months.
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Water Estimator Vocabulary

People in Household

This information is printed on your billing statement. We have prefilled this field based on the details we have on file for your account.

The number of people regularly living in your home directly impacts your indoor water budget. If this number is incorrect or has changed, please let us know!

How to find it on your bill:
For step-by-step instructions, please visit our billing guide: How to Read Your Bill
People in Household on Bill

Need to update it?
If it is incorrect, please fill out and return our Adjustment Form: Adjustment form
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Water Estimator Vocabulary

Gallons Per Day

Gallons per day is the daily indoor water allocation per person in the household. This includes all indoor water use, such as showers and washing clothes and dishes.
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Water Estimator Vocabulary

Irrigated Landscape Area

This information is printed on your billing statement. We have prefilled this field based on the details we have on file for your account.

The size of your irrigated landscape area directly affects your outdoor water budget. If this information is incorrect or has changed, please let us know!

How to find it on your bill:
For step-by-step instructions, please visit our billing guide: How to Read Your Bill
Irrigated Landscape Area on Bill

Need to update it?
If it is incorrect, please fill out and return our Adjustment Form: Adjustment form
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Water Estimator Vocabulary

EvapoTranspiration Rate

Evapotranspiration (ET) is the amount of water used (transpired) by a particular plant species combined with the amount of water lost (evaporated) from the surface of the soil under measured weather conditions during the billing period based on daily weather data acquired from the HydroPoint Climate Center Climate IQ Service (HydroPoint). HydroPoint provides American Society of Civil Engineers Penman-Monteith ET data every day. Western Water’s service area has more than 450 individual weather microzones. Weather changes are accurately updated daily for every account in Western Water’s retail service areas.
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Water Estimator Vocabulary

Landscape Efficiency Factor

The Landscape Efficiency Factor (LEF) is a number that helps estimate how much water is needed to keep water-wise landscapes healthy. It considers both how well irrigation systems work and how much water plants require.

At Western Water, the LEF is part of your water budget calculation and reflects typical landscaping in our region. Our rate structure assumes most yards include a mix of grass, trees, shrubs, and ground cover. Customers who choose more drought-tolerant plants can easily stay within their outdoor water budget while maintaining a healthy yard.
  • Lower LEF = More efficient (uses less water)
  • Higher LEF = Less efficient (uses more water)
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If you have questions or need additional assistance, contact Western Water's Customer Service team at 951.571.7104 or email us.