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Your Storm Drainage and Sanitary Sewer Billing

Storm Drainage Billing

Storm Drainage charges are calculated annually and billed semi-annually; every property — commercial and residential — will be billed twice a year. Each property owner's Storm Drainage bill is based on a formula using the lot size, the total impervious (or impermeable) surface area, and our billing rates.

Impervious surfaces are areas in which runoff does not soak directly into the ground. These surfaces may include building roof tops, sidewalks, driveways, patios, swimming pools, etc.

The higher the percentage of impervious area on your property, the higher the likelihood for runoff to our system, and the higher your rate per 100 square feet of impervious surface. Conversely, the lower the percentage of impervious area, the less potential for runoff, and the lower your rate per 100 square feet of impervious surface.

Note: per city ordinance, we always use impervious area measurements to calculate storm drainage charges; we never attempt to measure the actual amount of water that runs off any property.

Use the Bill Calculator to estimate your bill.
Rates: Effective January 1, 2021

Calculate Your Storm Drainage Bill

Stormwater Rate Calculator (1/1/21 rates)  
Other paved or impervious area:
Assessor Parcel Area:

Sanitary Sewer Billing

Sanitary Sewer charges are billed monthly.

To reduce costs, and as a convenience to customers, we have developed a combination water-sewer bill in conjunction with the Denver Water Department. Denver Water is responsible for meter readings and for processing and sending out the combined bills. Sanitary Sewer charges are based on the water consumption metered by Denver Water.

Every residential sewer customer has a one-month winter billing period (February meter reading). Metered water consumption for this winter period establishes sanitary sewer charges (beginning with the March bill) for the entire year — until the next winter billing period. Even though your water use may increase during the summer, your sanitary sewer charges will remain constant.

The sanitary sewer charge for non-residential property is based on actual metered consumption, or minimum charge, in each billing period during the year.

Beginning on January 1, 2021, storm and sanitary rates will increase annually based on the percentage increase of the Consumer Price Index for Urban Consumers (CPI-U). 


Pay Your Bill Online

water drop and ripples

You can now pay your storm drainage bill online using StormPay with no additional fees.