It took about two weeks for Horizontal Boring & Tunneling Co. to drill a tunnel under Interstate 70 for installing a backup waterline to serve the northern areas of Hays.
The tunnel is 9 feet below I-70’s four traffic lanes, medians and paved shoulders, said Doug Godown, superintendent for Horizontal Boring, of Exeter, Neb. It runs for 206 feet from the south side of the interstate to the north, Godown said.
"We get a bit set up, and bore across," he said, explaining the process.
With a completion date of July 2020, the backup waterline project will include a booster station, all of it designed to serve the growing area of Hays north of I-70.
Midlands Contracting Inc., of Kearney, Neb., is the contractor on the $769,678 project.
"The work was supposed to start after the first of the year, but they started in mid-December," said Jeff Crispin, director of water resources for the City of Hays.
As it is now, the motels, hotels, stores, gas stations and restaurants clustered north of I-70 along US-183 highway get city water from one source, a 16-inch line that crosses under I-70 and an existing booster station on 41st Street.
The existing line and a 500,000-gallon water tower north of I-70 were built in 1993, when there were just a few businesses on the north side of the interstate.
Adding a second line and station will not only provide a backup if the existing line fails, but will also bring higher water pressure to the northwestern areas of the city, Crispin said.
The new line crosses I-70 at Hall Street, connecting a 12-inch water main from 45th and Hall to an existing dead-end line along 48th Street at the west property line of Carrico Implement.
To bore the tunnel, Godown explained that a boring machine pushed through a 24-inch steel pipe casing with a spinning auger inside of it. The steel casing was installed in 20-foot sections, each one welded to the other, and then the 12-inch waterline installed inside of that.
The tunnel has been closed off until underground utility contractor Midlands begins laying the remaining waterline, probably starting in two to three weeks, said Troy Cumpston, project manager for Midlands.
The waterline won’t be as deep as the tunnel, which was designed to leave room for other utility lines to come through.
"We come up right away as soon as we can and we’re about four feet deep for the rest of the line," said Cumpston.
The booster station will be built last, sitting on 4 acres of city-owned property along west 41st Street, east of Post Road near city water well No. 32, Crispin said.
Working in tandem with the existing underground booster station, the new booster station will have room to expand. It’ll be powered by electricity, with a standby generator if electricity goes out.
Pressure north of 41st Street is currently about 10 to 15 psi less than areas of Hays to the south, according to Crispin.
Pressure will improve once the waterline loop is in place with a continuous supply of water through both lines and booster stations, he told the city commission last fall.