Majority of tested homes in Columbia had no lead, safe copper levels in water
When the 2022 calendar year started, Columbia was under updated water quality parameters relating to testing for lead and copper. The city failed to conduct tests on water for those metals that year.
The city was made aware of the violation in February and took steps to rectify it. Columbia Water and Light announced results of the required testing Friday.
Out of the 100 service lines at single- and multi-family residences tested, 72 had no detectable lead in their water, 26 had lead below the actionable level and two had an above actionable level amount of lead. All 100 were below the actionable level for copper. Water in city mains do not have detectable lead, the city said. The city replaced all of its lead water mains in a project dating back 40 years.
"Lead in drinking water is primarily from materials and components associated with service lines and home plumbing," the city added.
More: Memo says staff, department structure blamed for Columbia's lack of water testing for lead, copper
Residences tested were those with known lead service lines, lead interior pipes or lead solder that joins copper pipes, the city said in its announcement. The next round of testing is scheduled in September.
At least 90% of test sites must not exceed actionable levels. In the case of lead, it is 15 parts per billion, while it is 1,300 ppb for copper. The city found that 90% of tests were at 2.64 ppb or below for lead.
For the two residences with lead levels above what is allowed, the city helped to "identify potential causes within the homes that may have contributed to the elevated results."
Additional samples were collected and tested from a different faucet in the residences and found that one residence still exceeded lead level limits. The city helped homeowners identify ways to mitigate lead levels through water service lines in the home.
"These measures resulted in a sample below the action level. Everyone who participated has received a letter detailing the results of their analysis," the city said.
More: City likely to contract with consultant for lead/copper testing in late April, early May
The city also received 62 requests for water testing apart from the 100 tests it was required to do. All results came back below actionable levels, the city said. Those who want their home's water tested can contact Deidra.McClendon@CoMo.gov to arrange it.
The city consulted with Black & Veatch Corp. on the state-required testing and is seeking a Drinking Water State Revolving Fund of up to $100,000 to map lead service lines.
The lead/copper rule relates to leaching of those two metals into water due to corrosion. Metal corrosion is more likely under acidic conditions. The city maintains a water pH between 8.1 and 9 and an alkalinity of more than 105 mg/L as corrosion prevention, previous Tribune reporting stated.
Because of how complicated the lead/copper rule is, returning the city to standardized testing was overlooked at the end of 2019 and going into 2020. Instead of testing 50 residential taps every three years, standardized testing requires the collection and analyzation of 100 samples, both in the first and second halves of the year. The city was placed back on standardized testing at the very end of 2021, but failed to conduct testing last year as required.
Charles Dunlap covers local government, community stories and other general subjects for the Tribune. You can reach him at cdunlap@columbiatribune.com or @CD_CDT on Twitter. Subscribe to support vital local journalism.
This article originally appeared on Columbia Daily Tribune: First 100 lead, copper water tests finished by city
