Frosh Pond is being drained and a fence erected around it this week in preparation for repair. The outer area of the pond, which extends underneath the sidewalk, will be filled in and the pond itself lined in order to stop the leakage that has been occurring for several years.
“The area under the sidewalk will be filled with high flow concrete, called CDF,” said Project Manager Elizabeth Kane. “CDF is structural fill that is fluid and self compacting. It’s easy to place in hard to access areas like this, and achieves design strength when cured.”
Once the concrete is in place grout will be injected, just to make sure all the ancillary spaces are filled up. The outer area is being filled in to provide structural support for the sidewalk, and also to help support the walls of the pond after the lining is installed.
The lining will probably be a polypropylene material often used in reservoirs, Kane said. It will be mechanically fastened to the bottom and sides of the pond, up to the underside of the decorative capstone on the top of the pond’s walls. Once in place, the joints will be heat-welded to make the lining watertight.
The pond has existed on campus in some form since the 1909 Alaska Yukon Pacific Exposition, when it was called Geyser Basin. It later became known as Frosh Pond, thanks to an old custom of throwing freshmen in the water. Regent Joseph Drumheller donated a fountain for the pond in 1961 to celebrate the University’s centennial.
“The intention is to not change the aesthetics of the pond at all, so color selection of the liner is an important issue,” Kane said. “We’re hoping to find a dark gray to put in there, but so far the closest we’ve come is black.”
A few piping modifications will also be done as part of the project, just to help with the overall function of Drumheller Fountain. Once the design is complete, the project will be put out for bid to private contractors.
Frosh Pond holds 1 million gallons of water, and has been leaking at the rate of 70 gallons a minute. Previous repair attempts have not been successful.
“We’re targeting spring break to get the actual work done so that it will have minimal impact on students, faculty and staff,” Kane said.
She said the infill portion of the project will require concrete mixer trucks on Rainier Vista and will mean some closure of the paved path leading from Stevens Way to the pond. But the major work should be done before students return and the pond should be ready for refilling by May 1.