The City of Rio Rancho decommissioned one sewage-treatment plan and is upgrading another to serve future development, save money and be more environmentally friendly.
At the Rio Rancho Governing Body meeting April 22, Utilities Director Jim Chiasson explained the project to decommission the 50-year-old Wastewater Treatment Plant 1 on Sara Road, move the sewage to Wastewater Treatment Plant 6 in the Cabezon subdivision and upgrade plant 6.
Five years ago, before Chiasson took his position in January 2017, the plan was to build a new plant on the site of Wastewater Treatment Plan 1, he said. However, the contractor couldn’t do the work within the city’s $25 million budget, which came from a ratepayer-funded loan.
So, Chiasson and his staff negotiated out of the contract and developed a new plan.
The city put a lift station, which pumps water from lower to higher elevation, on the plant 1 site and installed a force main line to use pressure to move wastewater from there to plant 6. The leftover money, in a separate project, is going to expansion and upgrades at plant 6, he said.
Once the new lift station was running, plant 1 was decommissioned April 24.
Utilities staff removed the sludge and cleaned basins in plant 1, and the contractor is finishing paving and construction cleanup.
Plant 6 has enough capacity to handle the 450,000 gallons per day of wastewater from plant 1, even before the upgrades are done, said city spokeswoman Annemarie Garcia in an email last week. If there were extra wastewater plant 6 couldn’t treat, the city would pipe it to Wastewater Treatment Plant 2, on Industrial Park Loop.
Huitt Zollars Inc. did the project engineering and oversight for about $897,000, and Albuquerque Underground Inc. built it for $5.9 million.
The utilities staff worked with the customers getting recycled water from plant 1, including Vista Verde Memorial Park, to make other arrangements. Chiasson said some customers could get recycled water from plants 2 or 6.
He said the new lift station on Sara included odor control that should be better for nearby residents and businesses. The site also has a new generator and transformer from PNM.
“That took a little bit of time, but that was a huge improvement, since the transformer was quite old,” he said.
The project included a new right-turn lane into the site to increase safety because semi-trucks delivering chemicals won’t have to swing out into traffic to make the necessary wide turn anymore.
Also, Lift Station 16 at Westside and NM 528 was upgraded and the direction it pumps was reversed. It used to pump uphill to plant 1, but now it pumps downhill to plant 6, meaning gravity will carry the wastewater and save power.
At plant 6, which is about a dozen years old, the city has added coarse screens and a building to house them.
“As the city grows, it’s not uncommon to see more and more stuff put down toilets that shouldn’t be, so this coarse screen is going to pull out a lot of that larger material so it doesn’t clog up the fine screens before the wastewater gets into further treatment,” Chiasson said.
Plant 6 upgrades also include a new generator pad, upgraded fine screens, and additional aeration basins and membranes to handle increased flow from plant 1 and new development. He said the plant’s capacity would increase from 1.2 million gallons a day to 1.8 million, covering the area for eight to 10 years into the future.
In addition, sludge from plant 6 previously had to be trucked to plant 2 for processing. The project will add a sludge-processing facility to plant 6, which will save time, gas and money by eliminating the six to eight truck trips per day, five or six days a week.
Chiasson said upgrades should alleviate smells at plant 6 because equipment for new or expanded processes is enclosed.
“We’re looking at substantial completion sometime in mid- to late October,” he said.
HDR Inc. did the engineering and is handling the oversight for plant 6 for not quite $1.5 million. RMCI Inc. is doing the construction for almost $13 million.
“We’ve consolidated the treatment over at Cabezon,” he said. “That means we need a little less operator time and effort, less chemicals, less electrical cost on the operations side.”
Even with the cost of getting out of the first contract, he said, the two projects combined are coming in $1.3 million under the loan amount, barring unforeseen changes.