Houston lifts boil order

On Tuesday, Houston officials lifted an order that had called for more than 2 million people in the city to boil their tap water before drinking or using it.
A boil order had been in effect since Sunday, when a power outage caused pressure to drop at a purification plant.
The order led to the closure of businesses and schools, the Houston Independent School District included. Classes were canceled Monday and Tuesday as a result. The city’s order was rescinded shortly before 7 a.m. on Tuesday.
Water quality samples sent to the Texas Commission on Environmental Quality confirmed that the tap water meets regulatory standards and is safe to drink, according to the city.
“In an abundance of caution,” Mayor Sylvester Turner said at a news conference Monday, the city issued a notice affecting all of Houston and some adjacent areas. This was after two transformers – a main one and its backup – “uniquely and coincidentally” failed at a water plant. Low pressure resulted from the plant’s inability to treat and pump water into the transmission system.
Turner said that backup power generators would not have made a difference because the issue was within the plant’s system. The plant couldn’t receive power because the transformers were down.
“Turner said the power system at the water plant undergoes regular maintenance, but he did not give a timeline for how often,” she said. “I have ordered a diagnostic review of the system to understand how the problem was possible and how it can be prevented,” said the mayor.
“Turner said that sixteen sensors marked dips below the minimum pressure levels required by the Texas Commission on Environmental Quality, fourteen of them for only two minutes, and two of them for nearly thirty minutes.”
There is typically enough pressure for water to flow out of leaky pipes. Bacteria near pipes can be sucked into the system when pressure is lost, creating a health risk.