Inflow & Infiltration

Point of Sale Inspection

The City of Orono requires property owners to obtain a Certificate of Inflow & Infiltration (I/I) Compliance from the City before selling or transferring title of property. Inspection of a sewer service line is required when a property connected to the city sanitary sewer is sold (Point of Sale). Properties that don’t pass inspection will be issued a correction notice.

Please email Kellie  or call her at 952-249-4686 to verify that your property is in need of certification before beginning the I/I certification process.

Application for inspection is on the left side of this page (in the navy blue bar). Once this application is filled out and you click "Submit", it will prompt you to make payment. Once payment it made, a notification is sent to City staff and we will contact you to schedule the inspection. 

  1. Kellie Hoen

    Public Works and Parks Administrative Assistant

What is Inflow and Infiltration (I/I)?

Inflow and Infiltration (I/I) is the excess flow of clear water into the City's sanitary sewer system. Because the sanitary sewer system was not designed to handle this excess clear water, it becomes overloaded during times of high groundwater or heavy rainfall. This can cause basement flooding or bypassing of raw wastewater to local streams and lakes

Inflow is when clear water from illegal connections of sump pumps, downspouts, and foundation drains is channeled directly into sanitary sewer pipes.

Infiltration is when groundwater seeps into sewer pipes via cracks or leaky joints.

Cross Connection. A cross connection is when a portion of the stormwater system is connected to the sanitary sewer system.  Often, this is a hose leading from the sump to a laundry tub or a floor drain or a sump pump with a hose emptying into a drain.  Cross connections are a significant cause of inflow and infiltration.

I-I stormwater pic

Why is I/I a problem?

The excess clear water from I/I problems uses sanitary sewer capacity needed for wastewater. The result is sewer backups and increased costs for needlessly putting clear water through the wastewater treatment process.  Water that goes down any drain in your house leads to the sanitary sewer system and eventually ends up at a wastewater treatment plant, where it is treated before being released back into the environment.  Wastewater from Orono travels through the City’s sanitary sewer system to the Metropolitan Wastewater Treatment Plant, which is operated by the Metropolitan Council Environmental Services Division (MCES).  MCES treats wastewater for communities in the seven county metropolitan area. The MCES, which provides regional wastewater collection and treatment for the metropolitan area, requires communities with excess I/I to invest in local reduction remedies and to urge compliance, incorporates surcharges for communities with excess I/I. Since sanitary sewer rates are based on the number of gallons that flow through the City sanitary sewer system, treating clear water is costly to everyone. 

Why is a Point of Sale inspection required?

The Point of Sale ordinance is intended to help reduce peak sanitary sewer flows caused by Inflow and Infiltration (I/I), or flow of clear water into the sanitary sewer system. The Metropolitan Council Environmental Services (MCES), which provides regional wastewater collection and treatment for the metropolitan area, requires the City of Orono to reduce peak flows to the regional wastewater collection system. These inspections allow the City to ensure that private properties have no illegal connections to the sanitary sewer system or pipe defects that contribute to excess peak flow discharges.

Who is subject to an inspection?  

Those properties connected to the Municipal Sanitary Sewer who do not have a valid certificate of I/I Compliance when one of the following situations occurs:

  • Prior to Sale:   All properties in Orono must be inspected and required to be in compliance before they can be sold. 
  • With Permits: Property owners who apply for sewer connection or disconnection permits will also be subject to an inspection

What is the fee?

The application fee is $250 for residential properties and $750 (per building) for commercial or multi-unit buildings.

I/I Inspections Program 

To comply with MCES directives regarding I/I, the City inspects homes and businesses in Orono to determine if roof drains, foundation drains, sump pumps, and other clear water sources are connected to the sanitary sewer system. The goal of this program is to reduce excessive flows that enter the sanitary sewer system so the City, and its utility customers, won't have to pay MCES surcharges.