How to Clean and Maintain a Backwater Valve


Backwater valves are mechanical valves that are installed in the drain lines as a way of preventing back-flow of dirty water and sewage into your house. They help ensure there is no back flow of water from the sewerage lines entering your home. In order to ensure you are protected against floods from the sewerage lines, you should ensure the backwater valves are clean. They should be cleaned at least once each year. Your local plumber will know exactly how to do this.

Signs your backwater valve needs maintenance

Backwater valves will tend to fail if you fail to carry out regular maintenance. If you notice water or sewage coming up into your drains you will know that you valve need to be cleaned. However you need to do regular maintenance to prevent this, before it’s making a mess in your home. You can do this maintenance your self, however if you have never clean a back water valve before, you may want a professional plumber to walk you through the process the first time.

How to clean your backwater valve

  • The valve is usually located in the basement or just outside the home where the drain lines come out of the house. There is usually a type of door or cover that must be removed before you can see the valve.
  • Once the cover is removed you will see a valve cap that you need to open.
  • Once this is open you will see a flap. When the water from the sewer begins so try to flow back into the home this flap with close. Upon visual inspection the valve can be manually closed with a gentle tug. If this is hard to close then your valve is probably stuck.
  • If the flap is stuck due to gunk or debris it cannot close and you will get sewage in your home. To remove the gunk and clean the valve you need to wear gloves and use a long-handled brush. Just scrub the top valve with the brush, then clean around the edges and just underneath the valve until it is free of gunk and will open and close easily. To aid in this cleaning you may want to open some faucets in the home allowing clean water to run over the valve while you are cleaning it.
  • After the cleaning is finished you need to replace the cap and the cover.

Because the valve flap has to be free to open in order to keep backwater from backing up into your home, keeping it clean and free from debris is very important. Most people have never thought of cleaning their back up valves yet it is very important to make sure it is working correctly before it’s needed. As you can see this can easily be done by the homeowner if he is able to locate the valve cover and follow these instructions.