Ajax water tank in need of repairs

The city of Aspen is seeking a firm to conduct a thorough structural evaluation of the Aspen Mountain Water Tank, which has the capacity to store 1 million gallons of municipal water.

The city issued a request for proposals in December for a firm to identify and document signs of movement, settlement, cracking or deterioration on the water tank, which sits in an area closed to ski traffic on Aspen Mountain, between the Little Nell and Shadow Mountain lifts. It is a partially buried, circular water tank that was constructed in 1978, and is showing signs of aging that require attention, Aspen Deputy Utilities Director Ryan Loebach said.

Inspections take place annually, Loebach said. Every five years, a comprehensive inspection is conducted on the water tank. The most recent evaluation found structural movement, cracking in the floor slab, separation at wall-to-floor joints and corrosion affecting several pieces of the water tank. 

“The tank was built in the ’70s, so essentially, we’re worried about settlement, deterioration of the concrete interior, and any separation of the joints, particularly from the floor to the tank wall, and looking to also identify any other corrosion that we can’t really see very well with remote-operated vehicles,” Loebach said. “The idea is you take the tank down for a period of time so we can have it dry for folks that really know their stuff to come and look at the tank for us and tell us what we need to get repaired to make sure we keep this asset going into the future.”

The city is looking for a firm to conduct a more thorough inspection of the identified areas of repair, and provide recommendations for repairs and long-term serviceability. 

The window of time to inspect the water tank is limited. It will likely take place in May, Loebach said, once the ski season is over and snow has melted off the tank and the surrounding unpaved mountain roads, but before the start of irrigation season when water use reaches its highest point in the year. 

The tank is in one of several in the city’s “gravity zone,” where treated municipal water reaches an adequate pressure range to then deliver the water to city customers. 

“There’s plenty of redundancy [in water storage] for us that’ll allow us to take it down for a short amount of time to perform this work,” Loebach said. 

The work is scheduled to take place before the city embarks on a $77.4 million project to renovate the aging Castle Creek water treatment facility later this year. The facility was constructed in 1965 and expanded in 1985, and has not seen any significant upgrades since. 

The project will rehabilitate existing facilities to increase performance and the ease of operation and maintenance activities at the water treatment facility above Castle Creek Road.  It will update the facility’s bleach and fluoride feed and storage systems, and address updates required by the Colorado Department of Public Health and Environment. 

Aspen City Council approved two contracts with The Haskell Company and Garver during a Jan. 13 regular meeting to deliver the first construction phase of the water treatment facility improvements. The two contracts totaled $15.9 million.

City council also approved 15% water rate increases this year to help pay for the water treatment project. Rates will step down until 2031 after the initial increase — in 2027 and 2028, rates will decrease 5% from this year, and from 2029-2031, rates will decrease 10% from this year.

The city is also planning to ask voters to approve an $85 million bond issuance in November that will go toward the project. The initial work on the water treatment facility is scheduled to begin in August, Loebach said.