Troy City Council tables partnership with King Engineering to evaluate sewers, eliminate inflow, infiltration
By Charles Bolinger
Editor • King Engineering and Construction, PLLC evaluated Troy’s sanitary sewer system for 2026. The 2026 sanitary sewer evaluation study (SSES) is meant to build upon previous studies. In 2024 and 2025, the SSES efforts identified manholes as the most significant and consistent contributors of inflow and infiltration (I&I).
Partnering with Public Works Director Rob Hancock, Jeff King, company president, gave the council an overview of the past two years’ work and more.
Hancock told the committee that smoke testing, a common industry practice, has not proven as successful from the public sewers but they did find a quite few private sewers that emitted smoke. Most of the city’s issues stem from manholes, Hancock said. King has two or three sewer sheds remaining in the older areas of town to do for public I&I. Hancock said while he doesn’t have the data to support it, he knows that the instance of bypass pumping have dropped significantly, which tells him they are making progress against I&I.
Summing up, it comes down to sump pumps and manhole issues in Troy, they agreed.
King Engineering provided Troy with four options:
First, they could continue the past efforts with targeted SSES for $69,000. The work would include 50,000 linear feet of smoke testing, 100 manhole inspections plus data collection, analysis and reporting.
Second, they could conduct systemwide manhole inspections, which would mean 1,192 manholes, full condition assessment and prioritization plus reporting and recommendations for $208,000
Third, they could expand the manhole program to inspect 500 manholes, assess and prioritize manhole conditions, plus reporting and recommendations for $98,000
Finally, there was a focused manhole program where about 300 manholes could be inspected, along with condition assessment and prioritization plus reporting and recommendations for $69,000
The 2025 SSES studied 56,120 linear feet of sanitary sewer line and 100 manholes in the Meadowlark and South Main sewer sheds. A total of 369 defects were detected during smoke testing last year. Of those, 173 defects, or 47%, were associated with public infrastructure and 196 defects, or (53%) were associated with private property connections. Hancock said the fourth option would provide the city with the most bang for its buck. King agreed, saying that it fits well with the city’s approach to rehabilitation. With 300 manholes, he recommended a three-tier priority system for repairs or replacement.
Other key findings included:
- 11 manholes with active groundwater infiltration
- 169 defective manhole frames and covers, mostly in ponding areas that allow direct surface inflow
- 50 manholes with structural deficiencies that require rehabilitation
- Two sewer main segments that require cured-in-place pipe (CIPP) lining
- 27 sump pumps, 153 downspouts and multiple area drains suspected of or confirmed to be connected to the sanitary sewers
- 72 of 100 inspected manholes showing at least one structural or operational defect
To correct the I&I issues, the three tiers are: immediate action items, public system rehabilitation and private property coordination.
Over the next two years, the 11 manholes noted above would be rehabilitated to stop the active infiltration; 13 more manholes where ponding is commonplace would also be attended to immediately and nine broken clean outs would be replaced
Next, over three to five years, starting in 2028, public manhole defects would be corrected, structural rehabilitation, sewer main repairs and an ongoing inspection program.
Finally, in 2031, private property coordination would commence, notifying property owners about improper connections and their effects; set up a sump pump and downspout disconnection program; consider rebates or assistance programs to encourage homeowners to remove improper connections; and private lateral repairs for potential cost-sharing of defective ones.
Using prior SSES findings, King Engineering recommended the third option. “This option provides the best value relative to cost and level of effort, expands manhole inspection coverage and establishes a practical phased approach to complete inspection of the remaining system over the next two years.”
City Administrator Jay Keeven said he wanted to write a resolution for a contract with King Engineering for the fourth choice above and have it ready for the next city council meeting in May before proceeding any further.
