Looking for Leaks
Sewer backups on a rainy day don't originate in the sewers. On a dry day in the heat of the summer, the public system works perfectly, no matter how many residents and students at Northern flush their toilets or take showers. The number of people who take showers and flush doesn't get any greater when it rains.
An Old Collection System
The 130 miles of sanitary sewer we took over in November of 1987 and now maintain came to us in very bad condition. The average age of all sanitary main in town is fifty years. Some of it is in surprisingly good shape. Much of it is not.
Water that should not be in the sanitary system enters it through cracks in the mains, improperly connected house service laterals, and something called "infiltration," in which water travels from where there's more of it (the ground during wet weather) to where there's less of it (the sanitary sewer) through osmosis.
SSES
As part of ongoing sanitary sewer improvement planning, DeKalb Sanitary District do testing to evaluate the condition of the sanitary sewers.
These kinds of tests are used:
- A television camera is inserted into the main sewer lines to observe their conditions. Water is pumped into adjacent street storm sewers to look for cross flooding.
- Manholes are inspected to identify those in need of repair.
- A non-toxic smoke is blown into the sanitary sewer mains and used as a visual tracer to help determine the condition of the sewer pipes.
Restoring Integrity
DeKalb Sanitary District has aggressively been attacking intrusions of storm and groundwater into the sanitary collection system by
- repairing and replacing old public sanitary sewer mains
- making sure new sewer connections are done right
- helping homeowners find and correct illegal installations
- educating people about the need to keep storm water out of the sanitary system
- working with the City of DeKalb to restore storm system integrity