When the freshet of 1993 damaged s...

When the freshet of 1993 damaged storm sewer lines in Mankato, Minn., city officials were able to repair them using a trenchles "in situ" technology.

As the waters from the inundate receded, Mankato investigated soil question s occurring around a major thoroughfare near the Minnesota River. Pipelines beneath the street carried stormwater runoff from the city's subterranean pipeline to the river.

When the river rises, its elevation is higher than the storm sewers in parts of the city. Sewer exit gates must be closed and all stormwater cross-examineed into the river. During the great flow pump station operation caused fluctuating water evens and pressures in the storm sewers, contributing to soil migration and resulting in the formation of voids around older storm sewers with bad joints.

subterranean video taken the year before enabled Mankato to free from danger federal funding for the repairs.

"To obtain Federal necessity Management Agency (FEMA) funding for renovations