OARS-OSIS Augmentation & Relief Sewer

The American Council of Engineering Companies (ACEC) of Ohio awarded DLZ with an Outstanding Achievement Award for the OARS-OSIS Augmentation & Relief Sewer project in Columbus. This prestigious award is given to engineering firms for projects that demonstrate a high degree of achievement, value and ingenuity. Congratulations to all the award winners!

The new OARS 20-foot diameter, 23,300-foot long tunnel provides wet weather relief to the existing OSIS Sewer, the main combined sewer through downtown Columbus. Read more about OARS