Sewer Billing

OMWD provides sewer service to the communities of 4S Ranch, Rancho Cielo, Santaluz, and Black Mountain Ranch/Heritage Bluffs. Within OMWD’s boundaries, seven other agencies provide sewer service, depending on property location: City of Encinitas, City of San Diego, City of Solana Beach, Leucadia Wastewater District, Rancho Santa Fe Community Services District, Whispering Palms CSD, and Fairbanks Ranch CSD.

Many agencies providing sewer service, including OMWD, calculate sewer bills based in part on water consumption at the property. Therefore, higher water consumption can lead to higher sewer bills. For those customers whose water and sewer needs are served by different agencies, water usage data may be exchanged between agencies. For example:

  • For customers who receive a sewer bill from OMWD and a water bill from the City of San Diego, the City provides water usage data to OMWD.
  • For customers who receive a sewer bill from the City of San Diego and a water bill from OMWD, OMWD provides monthly water usage data to the City. The City bases the sewer charge on winter usage. If a customer’s water usage is higher this winter than it was in the previous year, the sewer bill may also be higher. For questions about how the City calculates sewer bills, visit the City’s website.

OMWD sewer service charges are calculated once a year and most customers pay for sewer service on their property tax bills to the County of San Diego’s Tax Collector office. Each parcel receives one sewer assessment. Typically, each parcel is assigned one equivalent dwelling unit. If a parcel has multiple water meters, the property tax bill will reflect a total of all sewer assessments. Irrigation meters are not included in any calculations.

OMWD’s Single-Family Calculation

Sewer fees are made up of two components: the system access charge, and the sewer usage charge. The system access charge is a flat fee charged annually for each parcel. The sewer usage charge is a per-unit charge based on potable water consumption during months with the lowest consumption. Water meter reads for December, January, February, and March are considered. The lowest monthly usage is multiplied by 12 (months) to arrive at the annual consumption, which is multiplied by the commodity rate to determine the sewer usage charge. If the lowest monthly usage exceeds 10 units, a maximum of 10 units will be used for this calculation.

Example:  If the lowest month’s water consumption is 5 units, this multiplied by 12 to arrive at an annual consumption of 60 units, which is multiplied by the commodity rate of $6.39 per unit for a total sewer usage charge of $383.39.

$383.39                Sewer usage charge

$175.81                 System access charge

$559.20*              Total sewer assessment on property tax bill

*If the total bill calculation is not an even number, the usage charge will be rounded down $0.01 as the tax bill must be evenly divisible by two.

Commercial and Multi-Family Properties

There are some accounts where a single water meter is serving multiple properties or parcels. The consumption for each parcel is calculated by computing the total annual water usage for from July’s read to June’s read and dividing it among the total number of parcels.

Example: The total potable water consumption on 16 multi-family parcels for July through June is 712. This equates to 44.50 units per parcel; multiplied by the commodity rate of $6.39, for a total sewer usage charge of $284.35.

$284.35        Sewer usage charge

$175.81         System access charge

$460.16         Total assessment on property tax bill

Each of the 16 parcels would be charged $460.16.

Similar to the above calculation of multi-family accounts, consumption for commercial accounts is calculated by computing the total annual usage from July’s read to June’s read. The rate per unit is determined by the sewer classification for the business (C1, C2, or C3).