GRIFFITH — The town has been conducting special smoke tests to stop rainwater from infiltrating the sanitary system.
The ultimate purpose of the testing is to comply with the Clean Water Act, said Town Council President Rick Ryfa, R-3rd.
"The smoke testing is just one component the town is using to develop a comprehensive plan to eliminate the amount of flow we must send to (the) Hammond Sanitary District during heavier rain events," Ryfa said.
Wessler Engineering is doing the testing to identify areas where excessive rainwater gets into the sanitary system.
Ryfa said Wessler has now tested about 85% of the sanitary system and found 558 defects — with 50 of them considered as high priority.
There are eight types of defects detected, including 10 storm drain cross connections, 77 defective cleanouts, seven bad lateral connections and six downspout connections.
Ryfa said other defects include five basement/foundation drains, two defective sewer mains, one lift station — and 450 defective manhole covers.
"These are primarily holes in the top of the manhole covers that allows rain to seep through," Ryfa said.
He also said Griffith is under a 1997 Environmental Protection Agency consent decree that was updated in 2012.
The initial requirement was for the town to build a 10-million gallon basin — at a cost of up to $30 million — to contain rainwater.
"Griffith has had serious concerns about the cost and long-term effectiveness of building any new large capacity basins and have raised those concerns to the federal and state agencies and HSD," Ryfa said.
Ryfa added the Hammond Sanitary District may have come up with a viable solution that would eliminate the basin requirement.
"If approved, the alternative measures would save taxpayers in Hammond and Griffith tens of millions of dollars and not require constructing additional basins," Ryfa said. "I want to thank Mayor (Thomas) McDermott and the folks at HSD for working with Griffith to address these vital issues."
The consent decree says that Griffith will no longer pump sanitary water into the ditches, streams and rivers, regardless of how diluted it might be.
Ryfa said, over a decade ago, Griffith often had to pump water from its sanitary plant that eventually made its way into the Little Calumet River.
"We made some technical changes around the year 2013 that resulted in a significant decrease in these sanitary plant events," he said.
Afterward, the town went about six years with no such events except possibly for one instance, Ryfa said, adding that very heavy rainfall can be difficult for the system to keep up.
"When that happens, water is sent to a swamp that eventually makes its way to the Little Calumet River. While the water may be very diluted, it's still in violation of the Clean Water Act," he said.
If not diverted to the swamp, it would eventually back up into the streets or basements," Ryfa said.
Ryfa said Griffith will continue working with Hammond, EPA and the Indiana Department of Environmental management to resolve all concerns.