Consumer Services & Outreach
Impervious Area Charge
DC WASA has changed the way we calculate your sewer charges. We have lowered the rate for sewer service and are now including a special charge for properties that include surfaces water can't penetrate (impervious surfaces).
Impervious surfaces such as rooftops, paved driveways, patios, and parking lots, are major contributors to rainwater runoff entering the District's sewer system. They also add significantly to pollution in the Anacostia and Potomac rivers and Rock Creek.
The new Impervious Area Charge (IAC) is a fair way to distribute the cost of maintaining storm sewers and protecting area waterways because it is based on a property's contribution of rainwater to the District's sewer system. Because charges are based on the amount of impervious area on a property, owners of large office buildings, shopping centers and parking lots will be charged more than owners of modest residential dwellings.
All residential and commercial customers will be billed for IAC. The monthly IAC will be $2.20 per equivalent residential unit (ERU), based on the current 2010 rates.
Frequently Asked Questions
The Impervious Area Charge is part of DC WASA's investment in reducing pollution in the Anacostia and Potomac rivers and Rock Creek. The charge applies to all lots, parcels, properties and private streets in the District of Columbia.
For more information, download Impervious Surface FAQ (PDF 359 kb) .
Map highlighting impervious surface areas:
driveways, private walks, roof tops, and parking lots
- What is an Impervious Area Charge
(IAC)?
The IAC is based upon the amount of impervious surface on your
property. An impervious surface is a man-made surface that cannot
be easily penetrated by water, such as
- rooftops,
- driveways,
- patios,
- tennis courts,
- swimming pools,
- parking lots,
- and other paved areas.
- Why is the IAC necessary? The charge is necessary to recover the costs of the $2.2 billion federally mandated Combined Sewer Overflow Long-Term Control Plan (CSO LTCP) detailed in the "What We Do" area of this site. The 20-year plan will reduce the discharge of excess flows into local waterways from DC WASA combined sewer system.
- Why did DC WASA decide to defray the costs of the CSO LTCP in this manner? The DC WASA Board of Directors determined that the IAC is a more equitable way to recover the costs of the CSO LTCP than the volumetric charge (for water used), because the IAC is based on a property's contribution to rainwater runoff.
- Why has DC WASA decided to bill for this charge now? The CSO LTCP program is currently under way and the IAC is designed to cover program costs. Therefore, the charge is being designed now to reallocate costs from the sewer charge formerly appearing on the DC WASA bill to the IAC
- How is the amount of the charge determined? The charge is based on an Equivalent Residential Unit (ERU). An ERU is a statistical median of the amount of impervious surface area in a single-family residential property, measured in square feet. Initially, all residential customers will be assessed one ERU. All nonresidential customers will be assessed ERUs based on the total amount of impervious surface on each lot.
- Who sets the IAC? The DC WASA Board of Directors sets the IAC. Beginning October 2009, each ERU will be billed at $2.20 a month.
- Is the IAC a one-time fee? No. This is a monthly charge.
- Do other cities have an IAC? Yes. Other cities have this charge to cover the cost of managing pollution from rainwater runoff.
If You Have Questions or Comments
| info@dcwasa.com | |
| Phone | 202-354-3600 |
| Fax | 202-787-2795 |
| Customer Service 810 First St., NE, Suite 1100 Washington, DC 20002 |
Related Documents
MyAccount Login
- Pay bills
- Update Account
- View consumption
- View your Impervious Area Charge