In Derwood, sewer line replacement means new pipe for the private line from your house to WSSC Water's sewer. Since about two-thirds of homes here were built in the 1980s, replacement usually follows a sag, separated joints or root intrusion rather than worn-out old pipe. Call the number on this page to be connected with a local plumber in Derwood.
Derwood at a glance
Derwood is an unincorporated community just north of Rockville and southeast of Gaithersburg, close to the Shady Grove Metro and the Intercounty Connector. The median home was built in 1985, and only about 15 percent predate 1980. WSSC Water collects the sewage, and most of WSSC's Montgomery County flow is treated at DC Water's Blue Plains plant. Montgomery County assigns each property a water and sewer category, so if you're near the edges of the area, confirm your service.
Plastic sewer pipe from the 1980s doesn't rust like cast iron, but it has its own weak points. Joints can pull apart as soil settles, a poorly bedded section can sag and hold water, and roots can enter a loose joint. Decks, patios and additions built since the 1980s sometimes sit right on top of the original route, which affects both the method and the price.
What to do now
- If you have a backup, stop using water on the lowest level.
- Check whether neighbors are affected; if so, report it to WSSC Water at 301-206-4002.
- Find the cleanout, often near the foundation or at the front of the lot.
- Have the line cleared enough to use the house, and ask for a camera inspection at the same visit if possible.
- Review the footage with the plumber before choosing a repair or a replacement.
Symptom table
| Symptom | Likely cause |
|---|---|
| Backups that return within months | Root intrusion or a broken section |
| Water pooling in the line on camera | A sag or belly from settled soil |
| Clogs always at the same distance | Offset or separated joint |
| Gurgling lower-level toilet | Partial blockage in the main line |
Cost factors
- How much of the line needs to be replaced
- Depth and slope correction
- Bursting or lining versus open excavation
- Patios, decks and driveways over the route
- WSSC permit and inspection; work on the service line must be done by a plumber registered with WSSC Water
Ask the plumber to price both a section repair and a full replacement if the footage is borderline, so you can compare the two side by side before deciding.
Sewer Line Replacement questions in Derwood
Why would a fairly new house need its sewer line replaced?
What has the biggest effect on the cost of a sewer line replacement?
Is a backwater valve worth adding while the line is open?
How long does a sewer line replacement usually take?
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