Rat in Toilet? A New York Plumber’s Solution

For many New York City co-op and condo residents, the City’s rodent problem has taken an unexpected form. For decades, our team at Fred Smith Plumbing & Heating has heard stories of rats both appearing in and crawling out of toilet bowls in high-end apartment buildings. For the most part, these stories are hearsay (someone said he heard from someone else that a rat crawled out of someone’s toilet). Even though most of these stories are unsubstantiated, the stories do ring true. After all, this is New York; rats live among us. 

Recently, many Manhattan residential property managers have requested that we bring our plumbing troubleshooting skills to bear on this “rat-in-toilet” problem.  And, we have done so successfully.

Rats find many opportunities to enter buildings’ plumbing systems; sometimes, they breed in them. Rats can enter a building’s waste stack through the house trap and subsequently crawl up the waste line, across associated branch lines and into an unsuspecting tenant’s toilet bowl. Similarly, rats can enter the building’s vent stacks and fresh air inlets and find dry areas in which to build a nest. We have heard reports from property managers of rats penetrating as high as the 16thfloor! This happens more frequently than some New Yorkers would like to admit.

Our team documents rat activity with a SeeSnake camera, which allows an investigation of a building’s underground waste piping and sewer and vent stacks.  In one rat infested building, we documented a rat’s nest and rat droppings in the building’s fresh air inlet. In another building, we observed rat droppings deep in the air inlet near the house trap. We have also documented rats crawling up waste stacks as seen in the video posted below. 

A Toilet Rat Solution: Install a Backwater Valve on the Main Sewer Line

Once a rat infestation in the sewer or vent system is confirmed in a particular building, we install a backwater valve on the sewer main line. Depending on the requirements of the building, multiple backwater valves may be required.

Like any check valve, a backwater valve uses a hinged disc to prevent water from flowing backwards into the waste line. The hinged disc, located inside the valve, allows water and waste products to flow in one direction only: out of the building.  When back pressure builds in the street due to heavy rainfall, or other disturbances that result in sudden stress on city sewer lines, the disc swings shut and forms a seal against the valve seat and prevents backflow into the building system. Although backwater valves are not designed to prevent rats from crawling into the building’s waste system, they do block the rats and deter them from infiltrating the building’s waste pipes.

Ongoing Maintenance of a Backwater Valve

Once installed, the backwater valve should be cleaned and serviced bi-annually to ensure functionality. Moreover, the building staff should inspect the floor drains, air inlets and drainage piping to ensure that they are fitted with the proper covers. 

The NYC Department of Health Rat Information Portal provides helpful guidelines for property owners, and others, on what can be done to prevent rats on your property. You can check it out here:  https://www1.nyc.gov/site/doh/data/health-tools/rats-information-portal.page.

Fred Smith Plumbing & Heating encourages you to call if you have a “rat-in-toilet” problem in any residential condominium or cooperative building that you manage. We understand the sensitivity of this problem and work with discretion.