DANVILLE — A sanitary sewer assessment on about 20 percent of the city’s sewers shows the city has a lot of expensive sewer projects in its future.
RJN Group of Chicago gave a presentation to the Danville City Council Tuesday night on its findings. The city paid $1.7 million for the assessment.
The city has had sanitary sewer issues for decades. Residents and businesses in the last couple years have been paying increased sewer fees from the city and Danville Sanitary District.
The current city funding level for sanitary sewer infrastructure: $2,217,076.
A five-year estimate for sewer infrastructure needs is $38 million or about $7.6 million a year. This includes $25 million for sewer and manhole rehabilitation; $5 million estimated for 5th St. pump station elimination; $3 million for smaller basin/other manhole and sewer rehabilitation; $2.2 million for Ellsworth Pump Station replacement; $750,000 for Lynch Creak pump station upgrades; $600,000 for Devonshire and Bayview electrical upgrades and pump replacement; $500,000 each for Lakeview, Southgate and Wilken Road pump station upgrades (replacement too at Southgate); and $30,000 for Harrison Park rehabilitation.
The city’s backlog shows: $10 million for five-year pump station capital needs and $125 million for gravity sewers which is approximately based on $25 million need from assessment of 20 percent of the system. This represents rehabilitation of about 50-60 percent of the sanitary sewer system. If completed over 25 years, it represents rehabilitation of 2 percent of the system per year, according to city officials.
RJN Group presented the city with a five-phase rehabilitation plan with the phases of rehab ranging from $3 million to $7 million.
City Engineer Sam Cole said the sewer fee customers are paying also isn’t keeping up with inflation.
The city already has completed a $1.3 million rehabilitation project in the Jackson Street basin area.
RJN Group, which started working with the city three years ago, said reasons for the assessment were due to aging infrastructure, sanitary sewer overflows and basement backups, and for the city to have less reactive maintenance by being proactive.
The city identified areas of concern, with overflows and areas upstream of pump stations. The program’s objectives includes understanding the city’s sewer system capacity, reduce rainwater entering the system, develop recommendations and prepare a multi-phase plan.
If a sewer can be lined, it’s cheaper than replacement. A lot can be done trenchless at a cheaper cost.
Flow monitoring in the study area following 1.22 inches of rain within an hour, showed flows are 16 times the normal sanitary flow. Sewers are typically designed to handle up to four times the typical dry weather flow, RJN Group officials stated.
The city cannot convey capacity of flow, they said.
Smoke testing, manhole inspection and closed-circuit television inspection with a camera on a robot occurred of the city’s system showing leaks in the sewers. Public sector defects showed 180 smoking sanitary manholes,24 smoking storm inlets and 30 smoking sanitary mainlines. Private sector defects showed 160 smoking services, 30 smoking downspouts and 360 smoking cleanouts.
There were 800 manholes inspected and 90 percent of them need improvements. There are also 50 point repairs recommended from the CCTV inspection and 60 percent of the sewers need improvements. Some are deformed sewer pipes, offset sewer or broken service.
The recommendations focus on the public sector. Easy private sector fixes include cleanout caps, downspouts and window well covers.
Additional funding options include the infrastructure bill, Illinois Environmental Protection Agency State Revolving fund, and water pollution control loan program with new principal forgiveness for low/moderate income communities.
Submitting the project to the IEPA would cost $20,000, and the city would not be committed to utilizing the loan.
Aldermen asked about life spans of the work. Trenchless can be about 50 years.
Each phase of work also could last about 12 to 18 months, and can overlap.
Cole said the city initially selected the basins it did based on the history of sewer calls and backups.
“Problem areas are everywhere,” he said. The city owns 179 miles of gravity sewers and 12 miles of force mains.
Cole said the loan would be good for the city. Mayor Rickey Williams Jr. said the city needs to move forward with it to be proactive.
City officials too said in no way would the city have been able to do what it has done without the sewer fee increase. They understand the hardship on the public, but they say it’s the way forward.
Ward 7 Alderman Bob Iverson thinks the city has been using the money provided by the fee well.
Several alderman Tuesday night voiced support of the city seeking an IEPA loan.