Kristen, a staff member, summarized the Merle Hay storm-sewer work and said crews finished the largest box culvert installation faster than expected. She told the council the project installed about 1,575 linear feet of box culvert and placed approximately 1,000 tons of riprap; the total cost was “almost $6,000,000,” she said.

Work included extending storm sewer toward Madison Avenue and Merle Hay Road to follow connectivity called for in the city’s 2021 stormwater drainage study. Staff noted the project required deep culvert installation to serve the neighborhood, and as a result raised concerns about settlement along the Ring Road above the culvert. Kristen said the Ring Road is a private road through Merle Hay and was used as a haul road during construction, which increased compaction during the build; nonetheless, the city has observed localized settling and will investigate to determine causes and repairs.

Kristen said the construction team passed compaction tests during construction but one curb location shows the surface has been depressed, and the project team plans further investigation and repairs. She added that allowing a full winter freeze-thaw cycle can help some settlement to stabilize before repair work is completed.

For next year, staff plans to extend the storm sewer west on Airline to 60 Sixth Street and east on Madison just past 60 Fourth Street to provide capacity where existing storm sewer is undersized, Kristen said. She noted that the north portion of the Ring Road paving could only be done after winter and was completed earlier this spring.

Discussion: staff reported completion of major phases and noted settlement concerns on the private Ring Road that will require investigation and repair. Direction: staff will monitor and investigate the settling area and plan repairs after seasonal stabilization. No council vote or policy decision occurred during the presentation.