Inflow and Infiltration

Inflow and infiltration (I&I) is stormwater or groundwater that enters into the sanitary sewer system. Inflow water enters the sanitary sewer system through major defects and/or direct connections to the sanitary sewer system. Infiltration seeps into the sanitary sewer system through cracks, offset joints, defects in pipes and/or manholes.

I&I can cause the sanitary sewer system to become overloaded beyond the designed capacity of the pipes during a rain event. When the capacity of the pipes is exceeded, the excess wastewater looks for the lowest release point, which can result in sewer backups or sanitary sewer overflows.

• Basement backups.
• Sanitary sewer manhole overflows.
• Increased claims and claim-related costs associated with backups.
• Negative impact on the environment due to sewage overflow and contamination.
• Increased costs for utility customers due to stormwater being treated at the treatment plant unnecessarily.
• Decreased capacity of the sanitary sewer system.
• Increased costs to upsize pipes for I&I excess peak flows.

The Water Utilities Department is constantly evaluating and maintaining the public sanitary sewer system. This is accomplished by running a television camera through the pipes to find defects as well as smoke testing, dye testing, jetting, root removal and visual inspections. System repairs, replacements and corrections are made from these evaluations to reduce sources of I&I in the public sanitary sewer system.

Customer Responsibilities

Customers are responsible for ensuring that the private sanitary sewer system on your property is maintained properly to avoid sewer problems on your property and/or properties further downstream on the public system. Your private sanitary sewer system includes all the sewer plumbing on the property you own and your private sewer lateral.

What is a Private Sewer Lateral: The piping that connects a building's internal sewer plumbing to the public sanitary sewer system. The sewer lateral is part of the private plumbing system and is maintained by the property owner.

• Have private sewer lateral line televised and/or cleaned.
• Ensure that any drains that collect stormwater discharge to daylight when possible and are not connected to the sanitary sewer system.
• Ensure that sump pump discharges to daylight at least three feet from the foundation.*
• Ensure that gutter downspouts run onto a splash block and drain at least three feet away from your foundation. Downspouts can also be connected to underground drain tiles, wet basins, downspout gardens or some other means of moving the water away from the foundation.*
• Ensure that sump basin/sump pit discharges to daylight at least three feet from the foundation or is connected to a sump pump.*
• Ensure that your footing or foundation drains discharge to daylight at least three feet from the foundation or are connected to sump basins/sump pits.
• Ensure that your outdoor stairwell drains discharge to daylight at least three feet from the foundation if the grade of the landscape allows. If the grade does not allow discharge to daylight, connected to a sump basin/sump pit.*
• Ensure that your driveway or area drains discharge to daylight at least three feet from the foundation if the grade allows. If the grade does not allow discharge to daylight, connected to a sump basin/sump pit.*

*Contact the Lee's Summit Codes Administration Department for any necessary permits before proceeding with any plumbing work.