Wastewater Service Billing

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

• For customers who receive a wastewater service 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 wastewater service 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 wastewater service charge on winter usage. If a customer’s water usage is higher this winter than it was in the previous year, the wastewater service bill may also be higher. For questions about how the City calculates wastewater service bills, visit the City’s website.

OMWD wastewater service charges are calculated once a year and most customers pay for wastewater service on their property tax bills to the County of San Diego’s Tax Collector office. Each parcel receives one wastewater 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 wastewater assessments. Irrigation meters are not included in any calculations.

OMWD’s Single-Family Calculation

Wastewater service charges are made up of two components: the system access charge, and the wastewater usage charge. The system access charge is a flat fee charged annually for each parcel. The wastewater usage charge is a per-unit charge based on the minimum of potable water used in the winter months of December to March, since water use during winter months mainly reflects indoor water use.

OMWD uses the amount billed in the respective winter month. For example, December’s usage is based on usage reflected in December’s bill. 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 wastewater 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 $7.49 per unit for a total wastewater usage charge of $449.40.

$449.40                Wastewater usage charge

$217.59                 System access charge

$666.99*              Total 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 billed from July to June of the prior fiscal year, 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 $7.49, for a total wastewater usage charge of $359.52.

$359.52       Wastewater usage charge

$172.19         System access charge

$531.71         Total assessment on property tax bill

Each of the 16 parcels would be charged $531.71.

Similar to the above calculation of multi-family accounts, consumption for commercial accounts is calculated by computing the total annual water billed from July to June of the prior fiscal year. The rate per unit is determined by the wastewater classification for the business (Commercial–Group I or Group II).