For more than six decades, the wastewater treatment plant in Hastings has quietly operated near the city's historic downtown along the Mississippi River — with an environmental record that is one of the best in the country.

Now the Metropolitan Council is moving forward with longstanding plans to build a new $145 million wastewater treatment plant just outside town. Once the new plant opens in 2027, the old facility will be decommissioned, freeing up land for possible redevelopment near the city's riverfront.

Hastings has done a good job revitalizing its historic downtown area, said Met Council Member Wendy Wulff, whose district includes the Dakota County seat. At the same time, she said, "as things turned around in downtown, we knew we'd have to eventually relocate the wastewater plant to meet demand."

The regional planning body says the existing plant, built in 1955, must be replaced because it's not feasible to upgrade it. Improvements are necessary to accommodate future growth in the southeast metro area, officials say, as well as anticipated changes in the way the plant is regulated.

A virtual public hearing on the plant's relocation will start at 6 p.m. Wednesday. Members of the public are encouraged to read and comment on the plan so the council can decide whether any final revisions are necessary before moving forward.

The plant, at 100 Lea St., is "physically constrained" and expected to exceed its existing treatment capacity of a little more than 2 million gallons of wastewater daily by 2050, according to a Met Council report.

Continuing service at the existing plant through 2040 would cost at least $26 million in upgrades, the report notes.

Plus, Hastings' "sewered population" of 22,800 could increase by 24% by 2040, with employment growing by 18% in the same period — resulting in a 51% hike in wastewater flow, according to council estimates.

The new plant will be located on a 221-acre site southeast of the city on the border of Hastings and Ravenna Township, where a gravel pit operated until 2018. Construction is expected to begin in 2024 and take two years.

The future plant will be able to treat 10 million gallons of wastewater a day, nearly five times the capacity of the current facility. The plant's long-term service area will include portions of Marshan, Nininger and Vermillion townships,

As is the case now, treated wastewater will be discharged into the Mississippi River and solids trucked to the council's metro treatment plant in St. Paul for incineration.

"The effluent that comes out of the plant is a lot cleaner than that water we're releasing it into," Wulff said.

In 2020 the plant completed 30 consecutive years of full compliance with state and federal clean-water discharge permit requirements, according to the Met Council. Only two other plants in the United States had slightly better records, and another plant was tied with Hastings.

As 2021 comes to a close, the Hastings plant will have 31 consecutive years of full compliance. "The plant been a good neighbor," Wulff said.

The council, which owns and operates the existing plant and has already approved its relocation, will decide Feb. 23 whether to approve the plan for the project before submitting it to the Minnesota Pollution Control Agency for approval in March.

"Based on its age and obsolescence, we're happy to see the Met Council make the investment in the new facility," said Hastings City Administrator Dan Wietecha. With the future growth predicted for the Hastings area, he said, "We don't want the plant to be maxxed out."

Wietecha said it's too early to say what will replace the existing plant on its site near downtown Hastings.

"That's seven or eight years out," he said, but he added that the site's proximity to the Mississippi River gives it a "unique advantage."