Water tank repair is on fast track
By Tamie Meck
Published Thursday, September 3, 2015 9:41 am
Photo by Tamie Meck From left, Scott Lanham with DNCI Construction Inc., SGM project engineer, Brandyn Bair, Town of Paonia public works director Travis Loberg and trustee David Bradford attend a site visit Monday at the town's one million-gallon water st
The Town of Paonia has struggled since May to fix a seemingly endless stream of problems associated with rehabilitation work on the one million-gallon Lower Lamborn
Mesa water treatment and storage facility.
"We anticipated completion of the project months ago," said town manager Jane Berry. Since problems first appeared, staff, trustees and engineers have been working to get the tank, which supplies in-town users with potable water, repaired and back on line.
The tank has been out of commission since December, leaving the town to rely on the two million-gallon Upper Lamborn Mesa facility to serve the needs of users and the 27 private water companies that rely on the town for treated water. Both facilities have been undergoing upgrades and repairs as part of the Lamborn Mesa Water System Improvements project. Approved about two years ago, the project is funded by a combination of grants and loans from the Colorado Department of Local Affairs, the Colorado Water Conservation District, and the Colorado Water Resources & Power Development Authority.
The 1MG facility project includes rehabilitation of the decades-old concrete tank and construction of a new roof to replace an aging and out-of-compliance metal and wood roof. Problems began after the tank was drained late last fall, the new roof was nearing completion, and the final application of the tank lining, designed to keep treated water from leaking out, was being applied. As the project was winding down in May, and shortly after irrigation ditches began flowing, pressure from water seeping up under the tank damaged the floor, the liner, and the tank walls where they meet roof trusses.
The water is believed to have come from a nearby irrigation ditch, and compounded by unseasonably heavy rainfall in May. How and why damage occurred, and how to fix the problem, has baffled engineers throughout the summer. They do agree, however, that if repairs had occurred and the tank was filled before irrigation water was turned on, pressure from inside the tank would have prevented any damage.
Berry said that staff, trustees, engineers and contractors are all committed to getting the facility back on line and have spent countless hours on finding a solution. The myriad of contract negotiations and other legalities have also kept town attorney David Marek busy. The public works department has installed a drainage project to divert ground water away from the structure to help prevent further damage.
Getting the tank back on line is a matter of public health, and "is our priority," said Berry.
The seriousness of the problem was highlighted early this summer when 11 water line breaks occurred during a three-week period. A mid-June break in a line on Lamborn Mesa left users without water for several hours.
In early August, trustees directed the Glenwood Springs engineering firm SGM, which was contracted in January to provide engineering work for rehabilitation of the facility, to study the problems and report back to the town. Representatives Chad Polson and Brandyn Bair presented their findings at the Aug. 25 board meeting. SGM created 266-page design specs manual for prospective bidders, with work to include installation of a new 6-inch concrete floor, repairs to the tank lining, and repairs to the walls joints caused by the shifting of the floor.
Trustees unanimously approved SGM's proposal, amended to clarify the timeline and specifics of the process. According to the timeline, the earliest the tank can be put in service is in mid-December. The town put out a call to contractors and held a mandatory pre-bid meeting Monday morning for floor repairs, followed by a site visit. Requests for Proposal will be published this week in the DCI and bids are due this Friday, with the award tentatively scheduled for a vote at the Sept. 8 board meeting.
Concrete work is anticipated to begin mid-September. The town wants the tank ready for disinfecting the first week of December, and back on-line by Dec. 11.
"It is a very tight schedule," but absolutely necessary, said Berry.
At the Aug. 25 meeting, and part of the overall water improvements project, trustees also voted to approve a change order for the upper Lamborn plant for installation by contractor Alpine C.M., Inc., of a temporary above-ground bypass pipe. The project is intended to "resolve conflicts between the existing German Creek Spring raw waterline and the new treatment plant building retaining wall."
The temporary pipe is intended to assure an uninterrupted supply of water to the plant during construction. According to a letter from the town's engineering firm, WestWater Engineering, the project is necessary to allow concrete work for the new treatment plant building to begin.
Cost installation for the 170-foot temporary bypass pipe is $6,986, and increases the total contract to $948,872.11.
Trustees also approved a reduction of $2,260 in the contract with Alpine C.M. for reseeding the area around the 1MG tank, which the town plans to complete next spring. The change was necessary to close the DOLA grant for the project. Cost to the town will only include re-seeding of grass around the treatment plant, according to Berry.
Also approved was the 13th amendment to WestWater Engineering contract to cover cost of administration and construction inspection related to the 1MG roof replacement project.
Total cost for the additional work is $16,485, which increases the engineering contract with WestWater to $396,979.