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How Annual Sewer Service Charges Are Calculated

The Bayshore Sanitary District (BSD) collects annual sewer services charges by placing the computed charges on the property tax roles of San Mateo County or by direct billing those customers who reside in the City and County of San Francisco (CCSF). The collected annual sewer service charges are used for the management, operation and maintenance of the BSD and to reimburse the CCSF for treatment.

Questions regarding individual billings should be addressed to Tom Yeager at 510-469-3156.

Residential Customers

For residential customers, the annual sewer service charge is computed as follows:

Total annual charge = $125xN + $5.00xQ

Where N = the number of dwelling units on an individual parcel and Q = the annual volume of water used on a parcel.

The annual volume of water used is based on water meter readings provided by San Francisco, Daly City, and Brisbane. The volume of water used to calculate the annual sewer service charge is either the total volume of water used in the previous year or 2 times the water used in the non-irrigation (winter) season. The lesser of these 2 volumes is used to compute the annual sewer service charge.

Non-residential (Commercial) Customers

For non-residential (commercial) customers, the annual sewer is computed as follows:

Total annual charge = $125xN + $5.00xQxLF

Where N = the number of individual businesses or dwelling units on an individual parcel and Q = the annual volume of water used on a parcel and LF is the loading factor and varies from 0.90 to 2.41 depending on the type of commercial business.

The annual volume of water used is based on water meter readings provided by San Francisco, Daly City, and Brisbane. The total annual volume of water is used to calculate the annual sewer service charge. No seasonal adjustment is made as it is assumed that no significant irrigation occurs on non-residential property.

Computations of the annual sewer service charge are made in May/June of each year and sent to San Mateo County in August in order to be placed on the property tax statements that are sent out in the fall.

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