Reconstruction of a Toledo water main brought the structure into the 21st century—but engineers used a 20th century relic to make it possible.

The East Side Water Main project, located between the city and Ohio's Perrysburg Township, is a finalist in the American Council of Engineering Companies'41st annual Engineering Excellence Awards. Detroit-based engineering firm Spalding DeDecker Associates Inc. performed construction layout for 1600 feet of 96-inch-diameter tunnel, situated under the Maumee River.

To eliminate the possibility of error, the team used a gyrocompass, a piece of mine surveying equipment dating back to the 1960s, and a theodolite survey device. The machines helped the crew measure the tunnel's precise direction from true north. Then, they repeated the process for the tunnel shaft and set the line for drilling machines to follow. The tools helped expedite the construction process.

The 24 winners in the specific awards categories—including the Grand Conceptor prize for the best overall achievement—will be presented at the association's annual awards gala on May 8, at Washington, D.C.'s Grand Hyatt Hotel. For more information or a list of finalists, visit