The City of Mercer Island Water Utility, under the City Public Works Department, provides water for about 22,699 residents living in the Mercer Island area, Washington. Established in 1960, the Mercer Island Water Department obtains its water supply as purchased from Seattle Public Utilities (SPU). The primary water source from SPU is the Cedar River Watershed, with the Tolt River’s South Fork providing an alternative supply.

Mercer Island Drinking Water Quality

Consumer Confidence Water Quality Reports

Under the authority of the Safe Drinking Water Act, the EPA requires Mercer Island City Water Department to assess local water quality each year and distribute a Consumer Confidence Water Quality Report. At WaterZen, we review these reports and make the information available, in a concise, straightforward, and easy-to-understand way. You can find CCR report on the Mercer Island City Water Department website.

Contact Mercer Island City Water Department Customer Service

Have a Question, Issue or Comment?

Main Customer Service

Physical Address:
9611 SE 36th St
Mercer Island, Washington 98040

206-275-7608
publicworks@mercergov.org

Emergency (24 hours - broken water main or pipeline, etc.)
206 275-7600

Pay Your City Of Mercer Island Water Bill

Already have an account?

If you already have an account, you just need to login to the City Of Mercer Island Water site. City Of Mercer Island Water accepts credit cards, debit, and direct deposit. Click here to login.

Want to create a new account?

You can create a new account on the City Of Mercer Island Water website. Once you create the account, you can setup payment with credit, debit, or direct deposit. Click here to create an account.

Want to pay without an account?

You can make a one-time payment without creating an account. You will need to have your credit or debit card in order to make the one time payment. Click here to make a one time payment.

How to Start Mercer Island Water Service

Starting Your Service

When you move to a new home in Mercer Island, you'll most likely already have running water, but you'll still need to set up water service with the City Of Mercer Island Water. Luckily, Mercer Island has made it pretty simple with the following online form. Starting service generally takes just two business days.

Click here to fill out a Start Service Form.

Stopping Your Service

When you move out of a home in Mercer Island, you'll need to stop your water service with the City Of Mercer Island Water, so you don't keep getting billed. Simply fill out the following online form. Stopping service normally takes just two business days.

Click here to fill out a Stop Service Form.

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