Your lateral pipe—the sewer pipe that connects your house to the main municipal sewer line under the street—is typically made out of a four-inch pipe that gets buried below the frost line in a sloped trench. The sloping aspect is critical here—it ensures proper drainage with the help of gravity.
There are several steps a sewer company in Bay City, MI will take when installing a residential sewer line. Here’s a quick overview of the process:
- Determining elevation: The first step is to determine how far the pipe will need to travel and the elevation at which you’ll need to install each end of the pipe. With residential installations, the pipe will begin where the main drain of the home exits the foundation. That line then travels downhill to the city branch or main, at a connection point referred to as a tap. Surveying equipment and GPS technology can be used to help determine the proper elevations for these purposes.
- Slope calculation: Based on the elevations and length of the pipe, you can determine the slope at which the pipe will be running. Subtract the final elevation from the starting elevation to determine the total elevation drop, and divide the drop by the total run of the pipe to calculate the slope. The minimum slope for laterals in most communities is 2 percent, which would equate to about two feet of drop per every 100 feet of run. The actual slope can be steeper, as long as it meets the minimum requirements of the code in your local area. However, too steep a slope will cause the liquids to run faster than solids, which can cause clogs, while a slope that’s too shallow results in improper drainage due to a lack of velocity.
- Digging: Trenching for the purposes of installing sewer laterals uses processes that disturb the surface as little as possible. Narrow trenches are best to minimize soil disturbance. The bottom of the trench must be made smooth and compacted and follow the desired slope. There will need to be a bedding material laid down to provide support for the pipe along its run. Sand is generally used because it is cheap and easier to slope than soil.
- Pipe installation: Once the line has been dug and the bed has been laid, the pipe can go in. You’ll generally start at the lower end of the pipe run and work up to the higher elevation at the house. Modern pipes are made out of PVC and joined with solvent glue or gasketed fittings. Here again, the standard pipe size is four inches in diameter, but there may be local codes that affect your pipe sizing. The female end of each pipe section should face uphill, which minimizes the chance of leaks at the joints as the waste travels through the pipes.
- Backfilling: Once the pipe is installed and has passed inspection, the trench is backfilled and the process is complete.
For more information about how a sewer company in Bay City, MI can help you by installing a residential sewer line, contact Thornton Brothers Sewer Service today.
Categorised in: Sewer Lines