If they treated the pipes they could stop infection to the water.
It was caused from the improper treatment that caused the lead aging pipes to leach lead into the water supply, leading to extremely elevated levels of the heavy metal neurotoxin.
The high lead in the water causing damage to the heart and kidneys. Children with elevated blood-lead levels may have risen from about 2.5% in 2013 to as much as 5% in 2015. It also caused Legionnaires' disease that killed 10 people and affected another 77.
The water was effected in April 2014 and went on for 4 years.