I'm considering building an Accessory Dwelling Unit (ADU) that's about 75 feet from my house (around 120 feet from the street) and I'm trying to get a handle on how much it will cost to run a new sewage line and water supply for it. I'm looking for estimates, but also have a couple of specific questions: 1) Could I tackle some of the work myself, like renting a trencher and laying down the PVC pipe? 2) Given the distance, will the slope be an issue when connecting to the sewer? I'm located in Maryland, just outside of D.C.
3 Answers
The cost really depends on your location. For instance, I know a friend who got quotes as low as $120 per square foot in North Carolina, but in California, it could easily jump to $300-$400 per square foot due to higher labor costs and regulations. Check local prices before you start anything!
You'll definitely need a proper slope for the sewage line—aim for about 1/4" to 1/8" drop per foot, which means you’ll need a drop of 15" to 30" for that 120 feet. If you’re lower than the main sewer line, you can connect directly; if not, you might need a pump. Team up with a utility company or a plumber for guidance; they can help out with inspections, which might save you a headache later on!
Good advice! Just make sure to get all necessary permits, or you might run into issues down the line.
I recently did something similar, and it was a lot more involved than I expected. I rented a mini excavator and did most of the digging myself, which ended up costing about $4,000 for everything, including a pump since the slope wasn't enough. I strongly recommend getting a pro for at least the critical parts—better safe than sorry!
Sounds like you had quite the journey with that project! It's definitely smart to weigh how much you can do safely.

Yeah, that's super true! If there are specific codes or regulations in your area, those can really affect the pricing.