Inflow and Infiltration

I/I Study

Inflow and infiltration occurs when clean ground water or storm water enters a sewer system through improper connections, cracked pipes, and defective joints.

Inflow is the tem used to explain when the surface water enters a sewer system through
Improper connections of yard, roof, and cellar drains, cracked pipes, holes in manhole covers, catch basins, and cross connections between storm and sanitary sewers.

Infiltration occurs when the ground water enters the wastewater system through deteriorated manholes, cracks, and leaks in the joints.

After a rain or snow storm the inflow and infiltration sources begin filling up the sanitary sewer systems with clear water.  These systems eventually become full resulting in the waste water to flow out at a significantly higher water level.  If drains and sanitary fixtures are below this overload level water will be able to flow back through the sanitary sewer pipe.  As a result, there will be flooding in homes and manholes will burst open, allowing the wastewater onto the streets. 

These are the following 3 methods of identifying Inflow and Infiltration:

  1. Smoke Testing 
  2. Flow Monitoring
  3. Television Inspection

Flow Monitoring is when special measuring devices are inserted into the sewer lines
to monitor the amount of water flowing through the wastewater system.


  • Call 1-877-637-9665


EnviroWaste offers 24 hour emergency response for situations such as hurricane relief, heavy rain events,sewer backups,
sewer line breaks, lift station outages, and any other
related natural or man made disasters.

EnviroWaste Services Group

  • Florida General Contractor
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  • Bonded and Insured
  • Equal Opportunity Employer
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