With funding from rate increase - significant upgrades of Water Treatment Plant
Built in 1995, the foundation and cement basin at Longmont’s Wade Gaddis Water Treatment Plant is crumbling.
“More importantly,” said Bob Allen, director of operations for Longmont Public Works & Natural Resources, “the site is too small to add all of the infrastructure needed for a modern water treatment plant.”
To rebuild the Wade Gaddis Plant and incorporate modern treatment technology would cost an estimated $70 million, according to a 2012 analysis by third-party consultant CH2M Hill. However, the consultant in 2012 estimated expanding the Nelson-Flanders Water Treatment Plant would cost an estimated $43 million. Current costs are estimated at $53 million.
“Expanding the Nelson-Flanders Water Treatment Plant is very cost-efficient,” Allen said. “It consolidates operations at a plant that has very low operating costs and allows Longmont to meet its long-term potable water needs.”
To fund the expansion, Longmont City Council on Dec. 3 unanimously voted to increase water rates by 9%. The rate hike, which takes effect in January, will increase the typical residential water bill from an average of $38.71 per month to $42.21 per month, according to Becky Doyle, rate analyst manager for the Department of Public Works and Natural Resources.
Once completed, the new raw water holding pond, effluent line and treatment equipment will replace the 15 million gallons of capacity at the Wade Gaddis Water Treatment Plant, as well as include much of the infrastructure required to add another 15 million gallons of capacity, which would allow Longmont to meet the water needs for the city’s future population.
Allen said the capacity will likely be added around 2030, but noted if the city grows beyond the framework outlined in the Envision Longmont multimodal and comprehensive plan, additional treatment capacity would be needed.
The Nelson-Flanders Water Treatment Plant, 13212 N. 53rd St., is near the confluence of several water sources, so consolidating water treatment operations at the location reduces risks for contamination and allows the city to eliminate its need for electrical pumps, as it distributes water solely using gravity.
Consolidating all of the water treatment operations in one building does, however, come with some risk. As such the expansion project will add some redundancies to ensure operations would never completely shut down. Those redundancies include a second raw water storage pond and secondary effluent line.
“Those are still a cheaper option than having to rebuild Wade Gaddis,” Allen said.
The Wade-Gaddis Water Treatment Plant also will be kept online in case of emergencies, such as a flood.
Construction of the Nelson-Flanders Water Treatment Plant expansion is expected to begin in 2021 and be completed by the middle of 2023.