Accessory Dwelling Unit

Accessory Dwelling Units (ADUs) are independent residential units which are located on an existing residential parcel. ADUs are permitted by King County and cities within Covington Water District's service area boundaries given certain land use restrictions. An ADU is a habitable living unit single-family dwelling that provides basic requirements for living, sleeping, eating, cooking, and
sanitation. Examples are detached apartments, mobile homes, and detached garages with a living space fitting the above definition.

An additional flat rate for each structure based on the meter size will be added to the monthly billing for an ADU only.

Additional Connection Charges Collected

All permitted structures on one tax parcel are allowed to be served by a single meter; the property owner must pay connection charges (Future Facilities Charge and Existing Capital Facilities Charge as identified in Rate Table Ill) for each structure as described in the District Administrative Code.  
ADUs may not be subdivided or otherwise segregated in ownership from the primary residential Structure without incurring additional connection charges and other fees and requirements identified in the current District Standards and Specifications. ADU structures will pay an additional flat rate and could require an upsize of the meter if fixtures exceed the 5/8 inch meter capacity.

Attached Accessory Dwelling Unit

In the event that the ADU is attached to the existing single family dwelling, payment of connection charges is not required unless the additional fixtures result in the need for a meter upsize.

Detached Structures (Not an Accessory Dwelling Unit)

Detached structures will be assessed connection charges if the demand for both the original house plus the detached structure exceeds the original meter, the property owner will be required to pay the current connection charges (identified in Rate Table Ill) for the new meter less the current cost of the existing meter being upsized. 

A detached structure is defined as a structure that has water fixtures but doesn't include living or cooking facilities.  This structure can/will be subject to periodic inspection to verify that its status hasn't changed to an ADU.  If it is determined that the structure has been changed to an ADU, the connection charges will be re-evaluated and the property could be subject to the additional fees based on the rules for an ADU as identified above.

Agreement for Additional Water Service Connection Upon Property Subdivision

Irrespective of the detached structure building type, the property owner will be required to enter into an agreement titled: Agreement for Additional Water Service Connections upon Property Subdivision. This agreement will be recorded with King County as a covenant attached to the property. For more information please contact the District at 253-631-0565.