Fixing a Sewer Challenge for an ADU
An ADU has an uphill battle to connect sewer service.
Our client was adding an ADU to her property in San Jose. Originally, we were contracted to connect the ADU to the sewer line in the front of the main home. This is a common configuration for an ADU and the homeowner and her ADU builder assumed this would work. Once we started, we quickly realized that the sewer out from the ADU was lower than the connection point into the main home’s sewer line out. In California, the typical 4″ sewer pipe is required to maintain at least a 2% slope. In this case, we were not able to achieve this with the ADU being three feet lower than the main home.
Instead of the proposed sewer line from the ADU to the front, we devised a new solution. A sewage pump is required whenever you need to elevate or “force” sewage up the slope. We installed a dual pump station between the ADU and the main home, then fed the discharge into the main home’s sewer line.
We installed a Liberty Pumps dual pump and basin solution. These were two 1 HP pumps inside a basin that captures the sewage and an external control panel that manages pump workload and provides redundance in case one fails. This pump solution should provide many years of service.
We also installed a new two-way cleanout in front of the ADU and replaced part of the sewer pipe in the front of the main home.
Our client was so pleased with our partnership that she left us a great review on Yelp. We hope she gets a lot of value from her investment and we appreciate the opportunity to be part of her ADU project.
More Helpful Resources to Help Guide Your Decision
Choosing the right contractor is a big decision. These resources will help you understand our process, compare services, and see why homeowners, contractors, and property owners trust Freedom Underground for their underground utility needs.
| Why Choose Freedom Underground | Lifetime Warranty | Customer Reviews |
| FAQ: What You Can Expect from Freedom Underground Plumbing | FAQ: General Engineering Contractor | Pricing for Standard Services |
| Water Leak Detection and Location Tools | Trenchless Technology | City and County Resources for Permits |
| Past Project Examples Browse examples of our completed projects, complete with photos and videos, so you can see the quality of work you can expect when you choose to partner with us. |
Our Customer-Focused Blog Helpful articles and insights for homeowners on plumbing, water, sewer, gas line, and electrical conduit issues. |
Explore Our Services The specific types of services we can help you with. |
