Flint Water Crisis Caused By Interrupted Corrosion Control: Investigating “Ground Zero” Home

TLDR

In April 2014, Flint, Michigan switched to the Flint River as a temporary drinking water source without implementing corrosion control. An intensive monitoring event at a Flint residence found all samples exceeded 15 μg/L lead, and forensic analysis linked the high lead to destabilization of lead‑bearing corrosion rust layers on a galvanized iron pipe downstream of a lead pipe. Lead levels rose from 104 to 707 μg/L over ten months, coinciding with water discoloration, and subsequent blood lead spikes in children prompted a state of emergency and public‑health interventions that likely prevented a worse exposure event.

Abstract

Flint, Michigan switched to the Flint River as a temporary drinking water source without implementing corrosion control in April 2014. Ten months later, water samples collected from a Flint residence revealed progressively rising water lead levels (104, 397, and 707 μg/L) coinciding with increasing water discoloration. An intensive follow-up monitoring event at this home investigated patterns of lead release by flow rate-all water samples contained lead above 15 μg/L and several exceeded hazardous waste levels (>5000 μg/L). Forensic evaluation of exhumed service line pipes compared to water contamination "fingerprint" analysis of trace elements, revealed that the immediate cause of the high water lead levels was the destabilization of lead-bearing corrosion rust layers that accumulated over decades on a galvanized iron pipe downstream of a lead pipe. After analysis of blood lead data revealed spiking lead in blood of Flint children in September 2015, a state of emergency was declared and public health interventions (distribution of filters and bottled water) likely averted an even worse exposure event due to rising water lead levels.