When digging is the better answer
Trenchless methods get most of the attention, but some lines need to be dug. If a section has collapsed, if a long belly needs its slope corrected, or if the old route runs somewhere it should not, open trench lets the crew see the pipe, re-bed it properly and lay new pipe at the right grade.
Open trench can also make sense where the line runs mostly under lawn or planting beds, so the surface is easy to restore, or where the lateral is shallow. The trade-off is disruption: a trench along the route, soil piles and restoration of whatever was on top.
How the work usually unfolds
- Before work
- Camera inspection, written scope, permit application and utility locating along the route.
- Day of excavation
- Surface is removed, the trench is dug to the pipe, and water use in the house is limited.
- Pipe replacement
- Old pipe is removed, bedding is prepared, and new pipe is laid at the planned slope with a cleanout as required.
- Before backfill
- Connections are made, flow is tested, and any required city inspection is completed with the trench open.
- Backfill and compaction
- Soil is returned in layers and compacted to reduce later settling.
- Restoration
- Lawn, concrete, pavers or planting are restored to the extent the written scope says.
Surfaces and what to clarify
| What sits above the line | Ask about |
|---|---|
| Lawn | Whether sod, seed or bare soil is the finish |
| Planting beds and irrigation | Who removes and replants, and whether sprinkler lines will be repaired |
| Concrete walkway or driveway | Saw-cut lines, patch versus full panel replacement, and finish matching |
| Pavers or brick | Whether they will be lifted and reset or replaced |
| Sidewalk or street | City permit and the city's restoration standard; check with the City of Whittier |
Get these into the written scope
- Length of pipe to be replaced and pipe material
- Planned slope and how it will be checked
- Cleanout location and type
- Permit handling and inspection scheduling
- Restoration of each surface, in specific terms
- What happens if unexpected conditions are found once the trench is open
Questions to ask
- Why open trench rather than a trenchless method for my line?
- How deep will the trench be at each end?
- Will the trench be shored if it is deep enough to need it?
- How long will the house be without normal drain use?
Common questions
Is open trench always more disruptive?
It disturbs more surface along the route. On a short, shallow line under lawn, the difference from trenchless may be modest.
Can I use my plumbing during the work?
Use is limited while the line is disconnected. Ask the contractor for the expected window.
Who handles the sidewalk if the line runs under it?
Work in the public right-of-way typically needs a city permit and restoration to city standards. Check with the City of Whittier.
General information for Whittier, not a quote or professional advice. In an emergency, call 911.