Frequently Asked Questions

A billing error occurred for wastewater services because what was adopted by City Council in October 2023 was not properly coded into the billing software system. 

The winter months used to calculate our wastewater estimates were incorrect resulting in over and undercharging on residential wastewater billing accounts. Water use data from Winter 2022-2023 should have been used as the basis for wastewater estimates, as that winter had unusually high rainfall and very little irrigation and outdoor water use. This approach was meant to fairly reflect actual indoor water use which would be returned to the sewer system as wastewater. However, the system was not programmed to lock in Winter 2022-2023 for 5 years, but automatically updated in spring 2024 and began using Winter 2023–2024 data instead to calculate wastewater rates.

Estimating wastewater flow is industry standard. Typically, wastewater providers try to estimate what percentage of potable water used at a home will return to the sewer system. The percentage differs depending on climate and property type. 

In Southern California, estimates typically utilize potable water usage data from winter months. Potable water is measured, and outdoor watering (which doesn’t return to the sewer system) is at its lowest during these months. 

In Escondido before 2023, it was assumed that 80% of potable water used at a Single-Family Residential home during the winter would be returned to the sewer system. The remaining 20% of water use was assumed to be outdoor use, including irrigation/filling a pool and wouldn’t be returned to the wastewater system. For multi-family and mobile home properties the return rate was set to 100%, because outdoor watering uses are negligible for these property types.

However, the winter of 2022/23 was historically wet (24 inches of rainfall was recorded between December 2022 to March 2023). The rain essentially eliminated the need to irrigate, and pools were being topped off with rainwater. As a result, in October 2023 Council agreed that the wastewater flow estimate would be 100% of the Winter 2022/23 water usage for the next 5 years. The historic rainfall effectively eliminated the need to use water outdoors, and it could be assumed that all water used at a home would be returned to the sewer system. 

If you received a check from the City, it is because your account was identified as one that was overbilled and due a credit. Rather than crediting your bill, the City decided to send you a check for the amount owed to return the money to you as quickly as possible. This is a legitimate refund from the City of Escondido. 

Unlike potable water, which is metered directly, wastewater is typically estimated based on how much potable water you use. It’s not practical or cost-effective to measure wastewater flow from each home because wastewater pipes are not pressurized or full and include solids. 

The amount of potable water used at a home is not equal to the water that is returned to the sewer system. Outdoor water use, including irrigation and filling pools, will not be returned to the sewer system.

Your bill changed for two reasons:

1. The amount of water you used in Winter 2022-2023 was different than Winter 2023-2024
2. Water use data from Winter 2022-2023 should have been used as the basis for wastewater estimates; however, the system was not programmed to lock in Winter 2022-2023 for 5 years, and instead used Winter 2023-2024 data to calculate wastewater rates.

Water usage patterns are highly variable, between and within households. Changes in any of the following could lead to a major bill difference:

• Occupancy (more people = more water use; less people = less water use)
• Appliances (replacing for more efficient fixtures, changes in frequency of use)
• Lifestyle habits (i.e. showering more or less often)
• Property type & size (landscaping/gardening needs, filling up your pool)
• Behavioral changes (hosting guests, vacations, working from home)
• Leaks

If you are receiving a bill credit, that means you used more water in Winter 2023/2024 than Winter 2022/2023. If you were underbilled, that means you used less water in Winter 2023/2024 than Winter 2022/2023.

Wastewater providers estimate wastewater flow based on winter water use, when outdoor water use is typically lowest. 

The wastewater winter water average is calculated by using your potable water meter reads from December to March and calculating a monthly average.

Before the 2023 Rate Study, the monthly average would be multiplied by a return factor (or the percentage of potable water that was expected to return to the sewer system). But in October 2023, the return factor was set to 100% as it was assumed that all potable water used at a home was returned to the sewer system because outdoor water use, which wouldn’t return to the sewer system, was minimal due to significant rain.  

Escondido City Council approved a new methodology in the 2023 rate study, locking in Winter 22/23 water usage data for 5 years. This new methodology was chosen because it was a really wet year and provided a very accurate estimate of indoor water usage, because outdoor watering needs were effectively eliminated. 

Your wastewater bill is based on water consumption, and usage patterns vary widely between households, even if the houses seem comparable. Major factors that could impact your water use and wastewater bill include:

• Household characteristics (number of occupants, lifestyle habits, appliance efficiency)
• Property type & size (landscaping, pools)
• Behavioral changes (hosting guests, vacations, working from home)
• Leaks

Learn more about water conservation, about filling your pool, and use the Water Calculator to estimate your household water use.

Wastewater charge = Monthly Fixed Charge + (estimated wastewater flow x rate per 1,000 gallons)

• The monthly fixed charge and the rate per thousand gallons is updated annually, on July 1^st. Current rates are posted here.
• If the Monthly Fixed Charge was $7.03 per month/per unit, this amount would be charged regardless of the amount of wastewater flow.
• The estimated wastewater flow is calculated by using your potable water meter reads from December 2022 – March 2023 and calculating a monthly average. Before the 2023 Rate Study this monthly average would be multiplied by a return factor, but Council agreed to remove the return factor and assume that all potable water was returned to the sewer system because irrigation needs were minimal due to significant rain.  
• The estimated wastewater flow is multiplied by a rate per 1,000 gallons. If the rate was $9.43, a customer would pay $9.43 for every 1,000 gallons of wastewater flow.  

For example: A home uses around 200 gallons of water a day during the winter period (December – March). With an average month having 30 days, the monthly average would equal 6,000 gallons of water (200 gallons x 30 days). 

$7.03 + (6 kgallons x $9.43)

$7.03 + $56.58 = $63.61

*Please note that the Monthly Fixed Charge and rate per 1,000 gallons used is updated each July 1.

Escondido City Council adopted wastewater rates that will be effective through December 31, 2028, and are based on water usage data from Winter 22/23. You will still see slight adjustments to your bill during these 5 years because monthly fixed charges and the rate per 1,000 gallons will be updated annually (on July 1) for wastewater.

However, during this 5-year period your wastewater flow estimate is set, and changes in behavior will not impact your wastewater bill. However, your behaviors and potable water use will impact your water bill. Here are some tips for water conservation and how to control your water bill: https://www.escondido.gov/747/Water-Conservation

If you had a leak anytime between December 2022 – March 2023, please contact the Utility Billing team at 760-839- 4682 or UBCustomerservice@escondido.gov with the following information:

1. when the leak started
2. when it was fixed
3. verification of the leak (repair receipt)

•    Learn more about the Water Shutoff Protection Act

•    Please contact the Utility Billing team at 760-839- 4682 or UBCustomerservice@escondido.gov to discuss arranging a payment plan for you. Remember: A customer shutoff is a last resort measure.

Your wastewater charges will be calculated using whichever is less:

• The city-average winter water use (i.e. for a Single-Family home the average is 5,852 gallons per month), per unit OR
•  Actual winter water use for the first complete winter period that the account was open. 

All customers who were undercharged will receive a letter in December. The letter will provide the total dollar amount the customer owes.  

Additionally, the total amount owed will be listed on bills starting in January 2026. The balance will decrease as you make payments and will remain on the bill until the total amount is paid in full.  

As a default, the customer will be automatically charged an additional $10 per month, per dwelling unit until the account is paid in full. This payment plan has been set up to help customers pay off their balance gradually.  

Alternate payment arrangements, including paying the debt in full (at any time) or reducing the additionally monthly charge can be arranged.  

Payment arrangements cannot be reduced below $5 per month and the total outstanding amount must be paid in full. To arrange an alternative plan please complete you must complete a form by December 23, 2025, which will be available online https://escondido.gov/FormCenter/Utilities-20/Alternative-Payment-Plan-for-Residential-135 or can be picked up in person at the Utility Billing Counter at City Hall.  

You are being back billed because you were undercharged due to a billing error. To correct this, you are being back billed for the amount that should have been charged originally.  

When some customers are not billed for services they’ve received, the financial burden shifts unfairly to others who are paying their share. Back-billing corrects this imbalance and ensures that everyone contributes equitably to the system we all rely on. 

Our sewer system require ongoing investment to remain safe and reliable. The revenue from wastewater charges funds critical projects—such as replacing aging pipes and upgrading treatment facilities—that protect public health and support future growth. Without recovering these costs, we risk delaying or canceling essential improvements, which could lead to higher costs and service disruptions down the road. 

To help you pay off your balance gradually and reduce potential financial burden, the default payment plan is an additional $10 per month, per dwelling unit until the account is paid in full.  

If you anticipate that this additional, temporary charge will result in financial hardship, you can request an alternative payment plan. You must complete a form by December 23, 2025, which will be available on the City’s website https://escondido.gov/FormCenter/Utilities-20/Alternative-Payment-Plan-for-Residential-135 or can be picked up in person at the Utility Billing Counter at City Hall.  

Yes. Starting in January, your bill will include both the additional monthly charge ($10 per month per dwelling unit), as well as list the total outstanding amount. You can choose to pay the total amount at any time.  

The City Council considered a report on September 17, 2025 which explained the billing error. After considering the impact of the error, the Council voted to back bill customers $10 per unit, per month until each account is paid in full.  

The staff report is available here (Item 8). 

The meeting recording is available here (Item 8). 

Rates were adopted by the City Council in October 2023 (Item 5). The rates were effective January 1, 2024 and included future rate adjustments through January 1, 2028. These rates will be in effect until the next rate study happens, currently scheduled for the end of 2028.  

Your wastewater charges help keep our community safe and our system reliable. Revenue collected from wastewater charges pays for maintaining and replacing sewer pipes, upgrading treatment facilities, meeting public health and environmental regulations, and planning future improvements.  

Without recovering these costs, we risk delaying or canceling essential improvements, which could lead to higher costs and service disruptions down the road.