Customized Water Budget

In order to calculate your water budget, EVWD takes several things into account, including property size, landscape area, number of residents, weather and more. This information helps the District accurately determine each customer’s unique water needs. Customers with special circumstances, like medical conditions, will be able to apply to the District for a variance for a larger budget.

Watch: How EVWD Calculates Your Water Budget

Rate Structure

The District’s budget-based rate structure applies to residential customers and reflects a 3-tier rate structure based on monthly usage. Commodity rates cover cost that vary based upon the amount of water delivered. 

Tier 1

Indoor Use Budget

  • Charged at the lowest rate
  • Based on the estimated number of occupants

Tier 1 Calculation Formula

Tier 2

Indoor Use Budget

  • Charged at slightly higher rate
  • This tier budget changes with the weather by increasing during warmer months and decreasing with cooler months.

Tier 2 Calculation Formula

Tier 3

Usage above tiers 1 and 2

  • Tier 3 is water used above your monthly budget from Tiers 1 and 2. It is considered inefficient water use
  • This tier is charged at the highest rate*

Revenue from Tier 3 is used to fund conservation programs to assist customers to reduce inefficient use.

EVWD is a not-for-profit public agency and is required by law to only charge its customers the costs associated with providing services. This rate structure has been designed so that the District is not dependent on Tier 3 revenue for operational stability. Beyond the actual cost of delivering Tier 3 water, revenue from this tier is used to expand water conservation programs and improve system efficiencies so that we may continue to deliver reliable services.

Tier 1: How Your Budget Is Calculated

Tier 1, your Indoor Use budget, is charged at the lowest rate and is based on the estimated number of occupants.  

Diagram showing the Tier 1 budget

Example

Here’s an example of a Tier 1 budget calculation for a home with 2 occupants during a 28-day billing cycle.

Diagram showing the tier 1 budget

Tier 2: How Your Budget Is Calculated

Tier 2, your Efficient Outdoor budget, is charged at a slightly higher rate. This tier budget changes with the weather by increasing during warmer months and decreasing with cooler months.

Use the formula below to estimate your Tier 2 (outdoor) budget.  Please note your budget adjusts to the weather by increasing during warmer months and decreasing in cooler months.  Some formula factors are dependent on the weather and are calculated at the time of billing.

Tier 2 Calculation (PDF)

Tier 2 water budget formula

Example

Here’s an example of a January Tier 2 budget calculation for a home with 1,200 sq.ft. of irrigable area.

Tier 2 water budget calculation example

EvapoTranspiration Rate*

Month Rate
January 2.48
February 2.91
March 4.39
April 5.29
May 6.13
June 6.82
July 6.93
August 7.09
September 5.50
October 4.05
November 2.79
December 2.29

*Note: EvapoTranspiration Rate (Eco) is determined by the weather.  The numbers below represent historical data from 2019 and can be used to estimate your budget.  Actual Eco rate is calculated at time of billing using current weather data.

Monthly Plant Factor

Month Rate
January 0.61
February 0.64
March 0.75
April 1.04
May 0.95
June 0.88
July 0.98
August 0.86
September 0.74
October 0.75
November 0.69
December 0.60