How to Hire a Sewer Contractor in Washington

Who licenses sewer contractors in Washington

Washington runs two systems through the Department of Labor and Industries, L&I. The first is contractor registration: any business that contracts for construction, including sewer excavation, must register as a general or specialty contractor, post a surety bond of thirty thousand dollars for a general or fifteen thousand for a specialty, and carry liability insurance. The second is the plumber certificate, issued to individuals, with journey-level and residential among its classes. Washington treats the side sewer as plumbing in most jurisdictions, so a crew replacing a lateral should include a certified plumber. L&I's Verify a Contractor, Tradesperson, or Business tool shows the registration, bond, insurance and infractions, and confirms a plumber's certificate. Seattle adds a layer: the Seattle Department of Construction and Inspections certifies registered side sewer contractors, and only they may work on a side sewer in the right-of-way or near a public main. Ask for the UBI number and check it first.

Permits and inspections

Seattle issues a side sewer permit through the Seattle Department of Construction and Inspections for repair, replacement or lining of the side sewer, including the right-of-way segment, and its inspectors look at the open trench before backfill or review the post-lining video; the Seattle Department of Transportation street use permit for the pavement cut is billed with it, and a registered side sewer contractor must be the applicant for right-of-way work. Spokane's Developer Services issues the sewer connection permit, with a separate right-of-way permit for the street. Expect an inspection before backfill everywhere. Washington 811 requires at least two full business days of notice, and the contractor should file the ticket and hold the permit.

Who owns the pipe under the street

Washington is a to-the-main state in its big cities. Seattle makes the owner responsible for the side sewer from the building to the public sewer under the street, sidewalk and pavement included, and Seattle Public Utilities maintains only the public main. Tacoma takes the same position, with the city keeping the main and the tees, wyes and risers on it. Spokane requires a licensed and bonded contractor for the right-of-way portion and treats the side sewer as the owner's project; confirm with its wastewater office where responsibility ends. Smaller Puget Sound districts vary; a few maintain the right-of-way segment, so ask. Shared side sewers are common in older Seattle neighborhoods, and the permit will require a plan for the neighbors. Washington has no point-of-sale side sewer inspection law.

What is under Washington, and why it shapes the bid

Puget Sound sits on glacial till, a dense mix of clay, sand and cobbles that holds a trench wall well but digs slowly and stops a bursting head when a boulder appears. Seattle's pre-1950 side sewers are often unreinforced concrete pipe, with vitrified clay elsewhere and Orangeburg in 1950s tracts; PVC arrives around 1975. Side sewers run deep on Seattle's hills, sometimes ten feet at the main, and groundwater in the outwash around Kent and Renton floods trenches in winter. East of the Cascades, Spokane trenches hit basalt within a few feet, so rock excavation belongs in a Spokane bid. Deep connections and old concrete pipe are why lining comes up so often.

For the lining methods themselves, the Sewer Pipe Lining Washington pipe lining guide goes into what fails in the ground here and which method fits.

What a Washington sewer bid must include

• The company's L&I contractor registration and UBI number as the Verify a Contractor tool shows them, with bond and insurance current.
• The certified plumber's L&I certificate, and in Seattle the firm's registered side sewer contractor status with the city.
• The side sewer permit and the street use permit named separately, with the inspection before backfill or the post-lining video.
• Depth to the main and the shoring method, plus a rock allowance in Spokane or dewatering near Kent.
• Whether the camera found a shared side sewer and how the neighbors' connections will be handled.

The full checklist, for any state, is on what a sewer bid should include.

Red flags in Washington

• A Washington bid with no UBI or L&I registration number, or one shown as suspended.
• A Seattle side sewer job in the street proposed by a company that is not a registered side sewer contractor with the city.
• A bid that stops at the property line in Seattle or Tacoma, where the owner is responsible to the main.
• No Washington 811 ticket before the dig.

Finding a sewer contractor in Washington

Washington does not yet have a verified contractor listed on this site, which is why the number on this page rings the national line. Call it or send the form with the property address and what the symptoms or the camera are showing, and we will locate a qualified sewer contractor near you, screen them the same way we screen every listing, and make the introduction. There is no charge for that. You can also search the CIPP Verified Installer directory yourself.

Estimates are free. Call now. (855) 804-1434

Where Washington property owners ask for help most

The rules above apply statewide; the communities below are the ones that generate the most questions. Cities with their own hiring page are linked.

Washington sewer contractor questions

What is a side sewer in Washington?

Side sewer is the Washington term for the lateral, the pipe that carries wastewater from a building to the public sewer main. Seattle, Tacoma and Spokane all use the term in their codes and permits, so a side sewer permit means the work other states call lateral work.

Who is responsible for the side sewer in Seattle?

The property owner, from the building all the way to the public sewer under the street, sidewalk and pavement included. Seattle Public Utilities maintains only the main. That is why Seattle requires a registered side sewer contractor for right-of-way work, and why Washington buyers in Seattle usually order a scope.

Do I check a plumber license or a contractor license in Washington?

Both. The company must be registered with Washington's Department of Labor and Industries as a contractor, with bond and insurance visible in the Verify a Contractor tool, and the person doing the plumbing must hold an L&I plumber certificate. One without the other is not legal.

Why do Seattle side sewer bids mention concrete pipe?

Many Seattle side sewers installed before about 1950 were unreinforced concrete, which cracks at the joints and lets roots in. A camera that shows concrete pipe usually shows offsets too. Washington contractors treat concrete as a lining candidate when the pipe holds its shape and a bursting candidate otherwise.

How much notice does Washington 811 require?

Washington law requires notice to the one-call center at least two full business days before excavation, not counting weekends and holidays. The contractor files the locate request and should give you the ticket number. In Seattle the side sewer permit must be in hand before the trench opens.

The short version for Washington

In Washington, scope the side sewer first. Run the UBI through L&I's Verify a Contractor tool and confirm the plumber's certificate, and in Seattle confirm the registered side sewer contractor status too. Confirm with the utility that the owner's responsibility runs to the main, because in the big cities it does, so the bid must price the street segment. Make sure both permits and the inspection are listed.

Estimates are free. Call now. (855) 804-1434

Sources checked for this page: www.lni.wa.gov/licensing-permits/contractors/register-as-a-c... · www.seattle.gov/DPD/Publications/CAM/cam503.pdf · www.seattle.gov/documents/departments/spu/services/drainages... · cityoftacoma.org/sidesewer · my.spokanecity.org/publicworks/wastewater/side-sewer-connect... · www.utc.wa.gov/am/node/159