Back water valves are frequently referred to as Back-up or Back Flow Preventers which can be a bit misleading. A Back Water Valve is installed to stop water/sewage surges from the main from coming into your house. They do not prevent back-ups caused by issues within your sewer service or due to long duration back-ups in the outside sewer system. A Back Water Valve is installed mid-line in your sanitary or storm service usually as close as possible to the exterior foundation wall in your basement. The valve is operated by a float. Once installed the valve will close if large amounts of water/sewage come up your service line, stopping it from coming into your interior service line/plumbing. This can prevent back-ups in these situations. However, If you have an issue within your service line that has caused a back-up or if the City main is completely full the valve at your foundation will stay closed. This essentially will block any water/sewage from exiting your house and depending on how long the line is full you may still experience a back-up if you continue to use your sewer and water. Back Water Valves are extremely useful in areas where storm or sanitary system surges are typical, in areas of high flood risk, or in areas where there is high ground water present. Give us a call to discuss and we would be happy to help determine if a Back Water Valve is right for you! To install a Back Water Valve a small excavation will be needed to access the pipe in your basement at your foundation wall. Thuro has licensed plumbers that can install the new valve in less than a day including re-concrete of the floor around the new valve. An inexpensive way to reduce your risk of back-ups and monitor if your sewer line is operating properly if you do have frequent issues is to install a water sensor alarm near your basement floor drain or other low lying location where water would tend to come into your house (basement shower or bath etc.). If your plumbing starts backing up sewage/water will come up out of these drains the alarm will go off to notify you. This way you can immediately stop using sewer and water until you can determine what the problem is. Preventing the mess and hassle of a full back-up. A water sensor we recommend is the Flo by Moen smart leak detector.