What is inflow and infiltration (I/I)?

View the Inflow and Infiltration Culprits Diagram (PDF)Inflow and infiltration (I/I) is the excess flow of clear water into the City's sanitary sewer system:

  • 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.

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.

Show All Answers

1. What is inflow and infiltration (I/I)?
2. What's the problem?
3. Why is Golden Valley a leader in this program?
4. When is Golden Valley's inspection required?
5. Why does the City require inspections only for homes that are for sale?
6. If I have the inspection and decide not to sell, do I still need to complete the repairs?
7. Can the buyers assume responsibility for the repairs?
8. How is Metropolitan Council Environmental Services (MCES) regulating I/I compliance?