Preventing Sewer Problems

Water/Wastewater in Basement
Water in a basement is usually caused by one of two sources — stormwater or wastewater. Stormwater can enter a basement through windows or by seeping through walls and floors. This is normally due to inadequate drainage or grading around a home or malfunctioning sump pumps, gutters or foundation drains.

Stormwater Infiltration
Stormwater can enter the sanitary sewer through leaking manhole covers, cracks in city or home sewer pipes, and from outdated roof or foundation drain connections. The amount of rainwater plus the normal wastewater flow can overwhelm the capacity of the sanitary sewer system causing it to back up. The City of Manhattan Water and Wastewater Division is working to cut down on stormwater infiltration by lining older sections of sewer to seal leaks and by raising manholes to prevent pooling of water.
Dispose of Household Hazardous Wastes Safely
Many household products are potentially hazardous to people and the environment and never should be flushed down drains, toilets, or storm sewers. Treatment plant workers can be injured and wastewater systems can be damaged as a result of improper disposal of hazardous materials.
Sewer Backups
Wastewater can enter a basement when the sanitary sewer backs up through floor drains. This can also happen for a variety of reasons including sewer blockages from grease, debris or tree roots; collapses or other deteriorated conditions in a city or home sewer line; and in older sections of town, infiltration by stormwater.
Help us prevent sewer backups

Fat, oil and grease (FOG)


Fat, oil and grease (FOG) aren't just bad for your arteries and waistline — they're bad for your home's plumbing system and sewer lines, too. Grease is one of the leading causes of dry weather sanitary sewer overflows, which are a potential threat to our health, homes and environment.


When you pour cooking grease down your drains, it may build up, block your pipes and cause rancid odors or messy, costly sewage backups in your home. It also clogs sewer lines. Running hot water after pouring grease down the drain does not resolve these issues. The grease cools, then congeals and coats pipes. When enough grease builds up, it can block your plumbing, city sewer lines and even pumps (customer grinder pumps or city sewer system pumps). Sanitary sewer overflows can occur in neighborhoods, creeks, parks, yards and streets, which result in expensive cleanup, repair and replacement of damaged property. The potential contact with bacteria and viruses carried in the backed up sewage could cause illness. 

Common sources of FOG include gravy, sauces, soups, cooking oil, butter, shortening, lard, margarine, milk, cream, sour cream, mayonnaise, food scraps, and oils from cooked meats.

What you can do
The City of Manhattan needs your cooperation — both residential and commercial customers — to keep our sewer system running properly and reduce the effects of FOG-related issues.
  • Scrape, wipe or sweep off FOG and food debris from pots, pans and tableware using a disposable paper towel before washing any item.
  • Pour all liquid oil and grease from cooking into a grease waste container such as a coffee can or jar. Once full, cap the container securely and freeze or dispose in the trash.
  • Put any spilled or waste food material into the trash, not down the garbage disposal.
  • Use screens over drains to catch food waste particles, then dispose of the waste particles in the trash.
  • Minimize use of your garbage disposal. Sinks are not trash cans.
  • Do not pour grease or oils down sink drains, floor drains or toilets.
For commercial entities, learn more about our Grease Management Permit Program.
Hazardous Chemicals
Other hazardous chemicals cannot be treated effectively by municipal wastewater systems and may reach local drinking water sources. When flushed into septic systems and other onsite systems, they can temporarily disrupt the biological processes in the tank and soil absorption field, allowing hazardous chemicals and untreated wastewater to reach groundwater. Some examples of hazardous household materials include:
Antifreeze Battery fluid Motor oil Oven cleaner
Paint Paint thinner Pesticides Polish
Rat poison Solvents Transmission fluid Varnish and wax

More Information About Hazardous Waste
Many of these materials can be recycled at the Riley County Household Hazardous Waste Facility, located at 6245 Tuttle Creek Blvd. For more information, please call 785-539-3202.