Sewer scope inspection: what the camera finds and why it is worth ordering

What the side sewer is, and why nobody else inspects it

Every home on public sewer has a side sewer: the private line that runs from the house, under the yard and usually under the sidewalk and street, to the public main. In most of King County the property owner is responsible for that entire run, including the portion under the public right-of-way. Seattle Public Utilities states this plainly for Seattle; most Eastside cities and sewer districts follow the same principle, and your agent can confirm the rule for your address.

A general home inspector runs water, checks drains and looks for slow flow, but the pipe itself is buried. Nothing about a clean bathroom tells you whether the line under the parking strip is intact. That is why the sewer scope is a separate inspection with its own technician, its own equipment and its own report.

The scope itself is straightforward. A technician feeds a camera on a flexible cable through a cleanout, or through a pulled toilet if the home has no accessible cleanout, and records the run to the main. You receive video and a written summary with distances marked from the entry point.

Which homes need it most

Any home on public sewer can benefit, but the case is strongest where the pipe is old or the ground is working against it. Seattle's older neighborhoods and the first-ring Eastside areas built before the 1980s were plumbed with clay or concrete pipe, and the joints in those materials loosen over decades. Homes from that era in Bellevue, Kirkland, Redmond, Mercer Island and Renton deserve a scope as a matter of course.

Mature trees are the other signal. Roots find moisture at pipe joints and grow into the line. A big maple or cedar between the house and the street is a reason to look, whatever the age of the house.

Newer construction with PVC or ABS pipe fails less often, but it does fail: crushed sections from construction equipment, poor slope, or a bad connection at the main. A scope on a newer home is cheap insurance relative to the purchase price, and many buyers order one anyway.

• Built before roughly 1980, or original plumbing never replaced
• Clay, concrete or cast-iron pipe noted in disclosures or by the home inspector
• Large trees or heavy landscaping between the house and the street
• History of slow drains, backups or a prior repair mentioned on the Form 17 seller disclosure

What the camera typically finds

Most reports fall into a handful of categories, and the technician will grade what they see. Root intrusion is the most common: fine roots at a joint that can be cut, or a mass that has cracked the pipe. Offsets happen when two sections of pipe shift so the ends no longer line up, catching debris. A belly is a low spot where the pipe has settled and water pools instead of draining; bellies collect solids and can lead to backups. Breaks and collapses are the serious end of the scale, sometimes visible as a section the camera cannot pass.

The report will note the pipe material, the approximate distance from the entry point to each finding, and often the depth. Those details matter because they tell a contractor where to dig and how much.

Read the findings as information, not a verdict. A single root ball at 30 feet is a different conversation from a collapsed section under the roadway. Your agent will talk through what the report means for your Form 35R response.

How the scope fits inside the Form 35 window

Form 35 ¶1(a) says the buyer's inspection may include a sewer line video inspection unless the parties checked the box saying it may not, so on a standard Form 35 you already have the right to scope. The form also notes that the inspection may require the inspector to remove toilets or fixtures to reach the line, and ¶2 requires you to restore the property to its prior condition afterward.

Order the scope at the same time you book the general inspection, ideally for the same day. The Inspection Period runs from mutual acceptance and is 10 calendar days if the blank was left empty. Your response, on Form 35R, has to be delivered before that period ends, and a scope report that arrives late does you no good.

If the general inspector recommends further evaluation of the sewer and you cannot get a scope inside the window, Form 35 ¶5 lets you give notice of additional inspections before the period expires. The period is then extended by the number of days written in ¶5, five if left blank, counted from the date of your notice. The notice must be delivered before the original period ends.

If the scope finds a problem

You have the same options as with any inspection finding under Form 35: approve and move on, request repairs or a modification of the agreement on Form 35R, give notice of additional inspections, or disapprove and terminate with your earnest money refunded. Which one fits is your agent's conversation with you, and it turns on the severity, the location and your plans for the property.

Repair scope drives cost more than anything else. Spot repairs to a single section cost far less than replacing the full run. Work under a sidewalk or street costs more than work in a lawn because it needs a right-of-way permit, traffic control and restoration of the pavement. Depth adds cost. Trenchless methods such as pipe bursting or lining avoid open trenches where the pipe qualifies. In Seattle, side sewer work requires a permit from the Seattle Department of Construction and Inspections and a registered side sewer contractor.

If the seller agrees to repairs, Form 35 ¶7 requires them to be completed no fewer than three days before the Closing Date unless a different number was written in, and you may order a re-scope by the same technician to confirm the work.