Accessory Dwelling Unit (ADU) Connections: Water, Sanitary, and Storm Sewer

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Source: Accessory Dwelling Unit (ADU) Connections: Water, Sanitary, and Storm Sewer ↗ Last modified: Sun, 19 Apr 2026 20:05:43 GMT

Label: Information

Connecting to City utilities

• Trees in the public right-of-way (street trees)
  • Work utilities around street trees rather than removing trees.
    • Removing a street tree? Learn more about tree removal and replanting ↗.
• ADU System Development Charge (SDC) Waiver ↗. If the ADU qualifies, the SDCs for the ADU will be waived.

Water connections

Water meter options

• What is it?

  • A water meter on the property keeps track of how much water is used each month.
  • Water Bureau will do all water work in the public right-of-way to the point of connection.

• Shared meter:

  • Serves both the primary structure and the ADU.
    • Water bill will be shared.
  • Determine the meter size. Count the total combined fixtures of the primary structure and ADU.
    • What counts as a fixture? How to determine meter size? Use the Residential Water Meter Request Form ↗.
  • New service line from the main in the street to the meter (if needed). Water Bureau installation fees are your (the applicant's) responsibility.

• Separate meter:

  • Serves only the ADU.
    • Water bill will be separate from the primary structure's.
  • Determine the meter size. Meter size is based on ADU fixtures only.
    • Use the Residential Water Meter Request Form ↗.
  • Water Bureau service installation fees apply.

Water supply requirements

• What is it?

  • The ability to shut off water.
  • The size of the water line coming to the buildings depends on the fixtures.

• What are you (the applicant) responsible for?

  • The connection from the backside of the water meter onto the private property.
    • You may need a plumbing permit ↗.

• Single supply line (if approved)

  • Conversions or additions:
    • Each fixture needs a shut-off valve.
    • Alternatively, install a whole-dwelling shut-off valve. This must be accessible to both units.
  • New construction: Each unit must have a control valve accessible to that unit.

• Line size

  • May need to increase if additional fixtures are added.