Drinkable water to be restored by mid-December. Multiple factors at play, another warns.

By Laura Lee

This is a developing story and will be updated.

Water restoration in the City of Asheville has a long-awaited timeline, according to Asheville City Council member Maggie Ullman.

In an Instagram video posted Friday morning, Ullman said there is a “Plan B” if the aluminum sulfate treatment (alum) treatment does not sufficiently reduce the sediment at the North Fork Reservoir. The plans will bring “an end to this crisis, hell or high water,” she said.

The U.S. Army Corps of Engineers (USACE) will build mobile filtration systems all along the dam, City Water Resources spokesperson Clay Chandler confirmed to BPR.

The mobile filters are designed to reduce the sediment in the water enough to allow it to be pushed out for distribution.

The mid-December timeline set by the USACE is a “best-case scenario,” Chandler said.

The USACE is “reasonably certain” that they can treat the million of gallons of water a day required to flush the system, Chandler said.

Beginning late Wednesday, the filtration system at North Fork has been able to treat some of the raw water from the reservoir, even at the high levels of turbidity after the storm.

Before this week, experts at the site hesitated to put water with such high levels of sediment into the North Fork filtration system- one of only two in the state that is not equipped to handle extreme turbidity.

READ MORE: Curtains, chlorine and caustic soda: What you need to know about the Asheville water outage

The existing North Fork system does not have the capacity to treat the full amount necessary to flush the system and return drinking water to the city: about 25 million gallons.

The USACE expects to build out the mobile filtration system in 35 days. The timeline presumes no delays from weather or construction.

If the plan is successful, the USACE-built system would produce about 15 million gallons of potable water with the existing North Fork filtration system producing the remaining 10 million gallons needed to flush the system.

A 35-day process from when the plan was approved by the USACE leadership on Wednesday would put the build completing around December 4.

“The target right now is to begin pushing nothing but potable water into the system sometime around Thanksgiving,” Chandler said.

Even after the water is in the filtration system, customers should expect to continue to be under a boil water notice for at least 10 days to two weeks as the system flushes.

Chandler said the filtration systems would remain at North Fork for the foreseeable future.

Original treatment plan continues

The USACE build does not affect the current treatment plan of applying the alum treatment to segments of the reservoir, Chandler said. Water resources does not expect the treatment would interfere with the alternative plan by the USACE

At a briefing earlier in the week, Chandler said he expected to have results of this week’s alum treatment by Monday.

The treatment was the second at the reservoir since the storm, but the first treatment had little to no effect on turbidity. At earlier briefings, Chandler said the high winds during the first treatment rendered it mostly ineffective.

If the second treatment was efficient in reducing the turbidity levels, water resources would likely apply another treatment next week, he said. The timing of a third treatment may be contingent on the contractor’s schedule.

Time also reduces turbidity levels, presuming no additional intervention by extreme weather, Chandler said in an earlier interview. “The only foolproof way to clear turbid water is to wait for those particles to decide they want to sink,” he said.

“Every day that passes…is going to help the clearing process,” Chandler said.

The alum treatment could outpace the build out of the mobile filtration system, but both plans are contingent on a variety of factors including weather and availability of materials and contractors.

In the meantime, Ullman expressed her joy at having an alternative plan. “I’m gonna celebrate that unknown is now known,” she said.

This story was updated to reflect the newest information about the USACE plans.