Unsafe Maui Water persists despite filters, reflecting California Wildfire lessons

The language is stark: People in torched areas of Maui should not try to filter their own drinking water because there is no “way to make it safe,” Maui County posted on its Instagram account this week. The message reached Anne Rillero and her husband Arnie in Kula, who were eating yet another meal of frozen pizza. The couple feels incredibly lucky they and their home survived the fires that raced across Maui in recent days, wiping most of Lahaina off the map. The number of confirmed fatalities was raised on Friday to 114 people.
When a neighbourhood organisation alerted them not to drink their water and to air out the house even if they run the tap, the couple decided to eat off paper plates to avoid exposure. No washing dishes.
“It’s alarming that it may be in the water system for a while,” said Rillero, a retired conservation communication specialist who has lived on the island for 22 years. Brita filters, devices connected to refrigerators or sinks and even robust, whole-home systems are unlikely to address the “extreme contamination” that can happen after a fire. “They will remove some of it, but levels that will be acutely and immediately toxic will get through,” said Andrew Whelton, a Purdue University researcher and expert in water contamination after wildfires in urban areas. The Maui fires damaged hundreds of drinking water pipes, resulting in a loss of pressure that can allow toxic chemicals along with metals and bacteria into water lines.
“You can pull in contaminated or dirty water from the outside, even when those lines are underground,” said David Cwiertny, a civil and environmental engineering professor at the University of Iowa. Hundreds of families could be in the same situation as the Rilleros in the Lahaina and Upper Kula areas, where people have been told to minimize any contact with county water including showers.In Lahaina alone, aerial imagery and damage assessment data generated by Vexcel Data show 460 buildings apparently undamaged by the fires. These are places where people are returning.