If your Kent property currently relies on a septic system and public sewer is available nearby, converting to sewer may provide a long-term alternative to repairing or replacing an aging septic system. But the first step is not excavation—it is determining whether your property can actually connect, which sewer utility serves the location, and what the connection will require.
Dirt Cheap Sewer helps property owners evaluate and complete the underground portion of septic-to-sewer conversion projects, including sewer routing, excavation, side sewer installation, connection work, and related site restoration based on the approved project scope.
Because sewer availability and connection requirements can vary by property, we start by looking at the actual conditions rather than assuming that a sewer main near your neighborhood automatically means your home can connect.
Why Convert a Septic System to Public Sewer?
A septic system can serve a property reliably for years, but it is also a private wastewater system that depends on the condition of the tank, drainfield, soil, piping, and available replacement area.
Property owners may begin considering sewer conversion when:
- The septic system is aging.
- The drainfield is showing signs of failure.
- Wastewater is backing up or draining poorly.
- Repeated septic repairs are becoming difficult to justify.
- A replacement system would be complicated by limited space.
- A public sewer line has become available near the property.
- Renovation or redevelopment changes the property's wastewater needs.
- The owner wants to evaluate sewer connection before investing in another septic system.
A failed septic system does not automatically mean that sewer conversion is possible, however. King County Public Health specifically advises property owners to evaluate both sewer connection and septic replacement when dealing with failing on-site sewage systems.
The practical question is therefore not simply, “Would I rather have sewer?”
It is:
“Is public sewer available to this property, will the serving utility authorize the connection, and what construction is required to make that connection correctly?”
That is where the evaluation begins.
Before Excavation, Confirm That the Conversion Is Feasible
A septic-to-sewer conversion involves more than installing a new pipe from the house toward the street.
Before construction begins, several questions normally need answers.
Which sewer agency serves the property?
The City of Kent operates a sanitary sewer utility, but the City states that it does not provide sewer service to every property within Kent. Some areas are served by other agencies, while some neighborhoods remain dependent on private septic systems.
The correct sewer purveyor should therefore be identified before connection requirements are assumed.
Is an existing public sewer close enough to serve the property?
Seeing a sewer line on a map does not necessarily establish that a property has an immediately usable connection.
The location, depth, capacity, connection point, easements, topography, and utility requirements can all affect feasibility.
Is there already a side sewer stub?
Some properties may have an existing stub extending from the public system toward the property. Others may require a new direct connection to the sewer main.
Kent's current sanitary sewer standards include specifications for side sewer stub connections and residential side sewer connections.
Can the building drain to the sewer by gravity?
Elevation matters.
If the building sewer is too low relative to the available public connection, a straightforward gravity connection may not be possible. Alternative designs can sometimes involve pumping equipment, but that should never be assumed until site elevations and utility requirements are confirmed.
Kent's sanitary sewer standards include a standard plan for low-pressure grinder-pump installations, demonstrating that pumped connections exist within the City's infrastructure standards in appropriate circumstances.
What permits and approvals are required?
Requirements can depend on:
- The serving sewer agency
- Connection location
- Work within the public right-of-way
- Street or sidewalk disturbance
- Septic decommissioning
- Plumbing modifications
- Property configuration
- Whether a sewer extension is required
What Happens During a Septic-to-Sewer Conversion?
Every project is different, but the underground construction portion of a conversion may involve several stages.
Locating the existing building sewer
The existing wastewater line leaving the building needs to be identified so the new sewer route can be planned.
Identifying the approved public sewer connection
The serving utility determines where and how a private side sewer may connect to its system.
Planning the new sewer route
The route may need to account for:
- Required slope
- Existing utilities
- Driveways
- Landscaping
- Retaining walls
- Structures
- Property boundaries
- Easements
- Street improvements
- Sewer depth
- Existing septic components
Excavating for the new side sewer
Once the route and connection are approved, excavation can begin.
Depending on site conditions, this may include work in the yard and potentially within a right-of-way or paved area.
Installing the new sewer line
The new side sewer must be installed according to applicable standards for materials, grade, bedding, cleanouts, connections, and inspection.
The City of Kent maintains specific sanitary sewer construction standards and standard plans for side sewer connections.
Connecting the building to public sewer
The property's wastewater plumbing is redirected from the septic system to the new sewer connection.
Addressing the old septic system
Once the property is connected to sewer, the existing septic tank and related components may need to be abandoned, pumped, removed, filled, or otherwise handled according to the requirements of the authority having jurisdiction.
In Kent, septic systems remain regulated through Public Health – Seattle & King County rather than directly through the City's septic program.
Backfilling and restoring disturbed areas
After inspection and approval, trenches can be backfilled and affected surfaces restored according to the contracted scope.
A Conversion Can Involve More Than One Agency and More Than One Contractor
It is important not to describe septic-to-sewer conversion as a single standardized package.
Depending on the property, additional work may be required outside the basic sewer installation.
Possible examples include:
- Septic tank pumping
- Septic tank removal or abandonment
- Electrical work
- Interior plumbing changes
- Engineering
- Surveying
- Sewer utility connection charges
- System development charges
- Right-of-way permits
- Street restoration
- Concrete replacement
- Landscaping
- Grinder-pump installation
- Easements
- Traffic control
- Sewer main extension
Kent's construction standards specifically note that direct connections can involve costs such as street repair, tapping charges, permits, and applicable system charges.
That does not mean every Kent conversion will involve every one of those items.
It means the project should be qualified before anyone promises a scope or price.
Is Public Sewer Available at Your Kent Property?
This is one of the most important questions in the entire conversion process.
Kent's own sewer mapping guidance explains that some areas within the city are served by other sewer agencies and that some neighborhoods do not yet have sewer lines at all. Those properties may still depend on private septic systems.
That means there is a significant difference between:
A sewer main already serving the property
and
A future sewer line shown somewhere in the surrounding area.
Kent also notes that many sewer extensions are development-driven rather than being installed according to a predictable City construction schedule.
For a homeowner considering conversion, this makes feasibility research essential.
Before planning construction, confirm:
- The serving sewer utility.
- Whether sewer service is currently available.
- The approved connection location.
- Whether a side sewer stub already exists.
- Whether sewer extension work is necessary.
- Whether gravity service is feasible.
- Applicable connection and permit requirements.
Dirt Cheap Sewer can evaluate the physical construction side of the project once the applicable utility requirements and site conditions are understood.
Some Properties May Require More Than a Standard Side Sewer
A nearby sewer system does not always mean there is already a connection ready at the property line.
In some situations, reaching public sewer could require:
- Extending a sewer main
- Crossing a paved area
- Working within an easement
- Obtaining permission for off-site work
- Installing a deeper sewer
- Meeting additional engineering requirements
- Coordinating improvements with the sewer purveyor
These conditions can significantly change the scope of a project.
For this reason, it is better to identify them during planning than after excavation begins.
If a substantial public sewer extension is necessary, the project may move beyond a straightforward residential side-sewer installation and require engineering and utility coordination before construction.
Start With Diagnosis and Feasibility
If your septic system is failing, connecting to sewer may be one possible solution—but it is not automatically the only solution.
King County Public Health provides separate guidance for owners dealing with failing septic systems and specifically addresses questions such as whether sewer connection is required and what happens if a sewer utility will not allow a property to connect.
Depending on the property, the practical options may include:
- Septic repair
- Septic replacement
- Public sewer connection
- Additional investigation before either option can be selected
Dirt Cheap Sewer's role should be to help determine what the sewer-side project actually involves rather than treating conversion as the answer before the basic facts are known.
Residential Sewer Connections
For a residential property, a conversion may involve connecting the home's existing wastewater plumbing to a new private side sewer leading to the approved public connection.
Conditions affecting the project can include:
- House elevation
- Distance to sewer
- Existing septic location
- Driveway placement
- Yard access
- Trees and landscaping
- Existing underground utilities
- Sewer depth
- Required restoration
Commercial Properties
Commercial sewer projects can involve different flows, design requirements, connection charges, engineering, and permitting considerations.
Kent's published sewer information distinguishes between residential and commercial utility billing, and its sewer planning materials indicate that development requirements can differ substantially from those for existing residences.
Commercial conversions should therefore be reviewed individually rather than treated as an expanded version of a residential connection.
Evaluate First. Excavate Second.
Septic-to-sewer conversion can become expensive quickly when critical assumptions are made too early.
A more useful process is to establish the project conditions first.
Step 1: Review the property and existing wastewater setup
Determine where wastewater currently exits the structure and how the septic system is arranged.
Step 2: Identify likely sewer access
Confirm the serving sewer utility and available connection information.
Step 3: Evaluate route and elevation
Determine whether a practical side-sewer route exists and whether gravity drainage appears feasible.
Step 4: Identify obstacles
Potential complications may include pavement, utilities, landscaping, walls, limited equipment access, deep sewer connections, or existing structures.
Step 5: Define the construction scope
Separate required sewer installation from other work such as septic decommissioning, engineering, electrical work, or surface restoration.
Step 6: Complete approved excavation and installation
Once applicable permits and approvals are in place, construction can proceed according to the approved scope and applicable standards.
Step 7: Inspection, backfill, and restoration
Required inspections occur before the trench is permanently closed, followed by restoration included in the project agreement.
This approach helps prevent the homeowner from making a major decision based on incomplete information.
Kent Is Not One Uniform Sewer Service Area
A generic city page should not imply that every Kent address has the same sewer conditions.
The City itself states that not every property is served by Kent utilities. Some areas are served by other agencies, and some neighborhoods remain on septic.
That creates legitimate property-by-property differences involving:
- Sewer jurisdiction
- Existing sewer infrastructure
- Connection availability
- Connection depth
- Future sewer extensions
- Existing side sewer stubs
- Required improvements
- Easements
- Public right-of-way work
Those differences are why a Kent septic-to-sewer page should focus on qualification and feasibility, not promise that every septic property can simply be connected to City sewer.
For questions regarding City of Kent sewer availability and new connections, Kent currently directs property owners to its Public Works sewer service resources.
Frequently Asked Questions About Septic-to-Sewer Conversion in Kent
Possibly. The first step is determining which sewer utility serves your property and whether an approved public sewer connection is available. The City of Kent specifically notes that it does not provide sewer service to every property within the city.
No. Kent states that some areas are served by other sewer agencies and that some neighborhoods within the City's service area still do not have sewer lines.
The old septic system normally must be addressed according to applicable King County Public Health requirements. The exact abandonment, pumping, filling, removal, documentation, and inspection requirements should be confirmed for the specific property and current rules before work begins.
Septic tank abandonment or removal requirements vary by project. We will identify the sewer construction portion of the conversion and clarify which septic-system work is included in your estimate before construction begins.
There is no responsible single price for every property.
Cost can depend on:
- Distance to the sewer
- Depth of the connection
- Excavation conditions
- Existing sewer stub availability
- Pavement or street work
- Required restoration
- Permits and utility charges
- Septic decommissioning
- Engineering
- Whether gravity drainage is possible
- Whether a sewer extension is required
A site-specific evaluation is more useful than a generic price range.
A sewer connection will generally require authorization from the applicable sewer utility, and additional permits may apply depending on the work.
Potentially, but a street crossing can substantially change the project. Utility authorization, pavement restoration, traffic control, right-of-way permitting, and connection requirements may apply.
The actual route should be evaluated before assuming the connection is practical.
The immediate priority is identifying the nature of the failure and determining what options are available. King County provides specific guidance for property owners dealing with failing septic systems, including evaluation of sewer connection versus continued on-site sewage treatment.
Sometimes parts of a project may be candidates for trenchless methods, but that depends on the required connection, pipe route, soil, utilities, access, elevation, and installation method.
A conversion should be evaluated first rather than assuming trenchless construction will work.
The construction duration depends on the actual scope.
Permitting, utility approval, engineering, sewer extensions, septic decommissioning, difficult excavation, or right-of-way work can affect the overall timeline.
That depends on the location and serving utility.
Because some Kent properties are served by agencies other than the City, the sewer purveyor should be identified during project qualification before connection requirements are assumed.
Find Out Whether Sewer Conversion Makes Sense for Your Kent Property
If you are considering replacing an aging septic system, dealing with septic problems, or simply want to know whether your property can connect to public sewer, start by determining what is actually possible at your address.
Dirt Cheap Sewer can help evaluate the sewer construction side of the project, identify potential routing and excavation challenges, and define what will be required before a new connection is installed.
Request a Septic-to-Sewer Conversion Evaluation
Or explore our Kent sewer and outdoor plumbing services for help with sewer lines, excavation, trenchless repair, drainage, water lines, inspections, and related underground infrastructure.