Flushing water mains continues to be the strategy to eliminate concerns about water quality in certain areas of the valley, Minot City Council members learned Monday.
Two residents from separate, affected areas asked the council to push the Public Works Department to correct the water problems. Both indicated they stopped drinking the water after a private water sample in northwest Minot tested positive for bacteria. The city's follow-up sampling has shown no bacteria.
"Can we get multiple water tests done over the course of a month to confirm the water is safe?" asked Nathan Mugaas, a resident of the old Lincoln School area in northwest Minot. "It just varies in quality from day to day and it really seems like it needs to bested from day to day."
Jason Sorenson, assistant public works director, said in the last week, the department has determined that the area affected in northwest Minot is relatively small, only about eight square blocks. The problem appears to be rust from old cast-iron water mains, he said.
The city has increased the chlorine in its pipes and established a flushing program from north to south in the affected area, introducing fresh water to try to clear the system.
"We are hoping it's a permanent solution," Sorenson said. "Sometimes it's just a matter of getting some high volume through the pipes, scour them and get the rust out."
Mugaas said he noticed water discoloration and odor after moving back into his flood-repaired home last December. This fall, an overflow valve on his nine-month-old water heater had to be replaced due to sediment in the water, he said.
"There's disagreement on what's going on but we know that something is going on," he said. "Can you, as city leaders, really help pressure the water department to get to the bottom of this problem, hold them accountable to get a resolution?"
Carolyn Moore, a resident of Green Valley in southeast Minot, reported damage to appliances installed new in her home after the flood. First District Health Unit tested the iron level in her water at 2.5 parts per million on a scale in which 0.3 ppm can cause staining of fixtures. Iron is not an element regulated in drinking water by health officials.
Moore said the city has been running water through a hose on a hydrant near her home on a continuous basis, which is helping to clear the water. But she questioned whether it is a long-term solution.
"I would like to see a permanent solution," she said. "The bottom line is even if there proves to be no safety concern with the water, there's definitely a quality concern. I think that deserves attention too."
Sorenson said there may have been a coating on cast-iron mains that wore away when water sat stagnant in the lines after the flood. It is unknown how long it might to to restore a coating, he said.
Asked by the council what the department's next step would be if flushing doesn't work, Sorenson's initial response was "more flushing." However, he added, the department might investigate whether any changes in treatment can help encourage coating of the pipe.
In other business, the council approved 23 requests that came through a review committee from residents seeking extensions on the temporary housing units that they acquired from the Federal Emergency Management Agency. The extensions carry a June 2014 deadline for removal.
The review committee will meet again Oct. 22 to consider additional requests. City planner Donna Bye reported the number of known units in use around the city now is up to 68, and not all owners have requested an extension. She said the city will order removal of units that don't have the extension permits.