A timeline of the water testing fiasco at the Jacob Riis Houses

City officials told residents at the New York City Housing Authority’s Jacob Riis Houses on Saturday the water was safe to drink again, and blamed the testing company for faulty results that showed arsenic in the water supply and left tenants without water for more than a week.

In a statement, Mayor Eric Adams said the city will pursue legal action against Environmental Monitoring and Technologies after it “introduced arsenic into the samples.” He also expressed doubt about subsequent tests produced by the company last week showing Legionella bacteria in the water at the East Village housing complex. A City Hall spokesperson said previously, when announcing the Legionella detection on Wednesday, that the administration expected the results were wrong, because the bacteria can not be spread through drinking water. 

Adams declared Saturday he drank the water at Jacob Riis himself after several new rounds of samples came back clean. 

“I know the last eight days have been unbearable for the residents of Jacob Riis Houses, but, this morning, the New York City Department of Health and Mental Hygiene reviewed the final test results for contaminants and found the water to be well within (Environmental Protection Agency) drinking water quality standards,” Adams said. “We can confidently say the water at Riis Houses is and has been free of any discernible amount of arsenic since the initial tests were initiated in August and meets EPA standards.”

See our timeline to keep track of the developments:

Thursday Aug. 4: NYCHA officials are alerted about cloudy water conditions at the houses, but do not order testing until eight days later The City reported. 

Friday Aug. 12: NYCHA has the Department of Environmental Protection test for e-coli and chlorine.

Tuesday Aug. 16 NYCHA announces that it’s OK to drink the tap water.

Friday Sept. 2: New York City Public Advocate Jumaane Williams holds a press conference at the Jacob Riis Houses to release a report documenting deplorable conditions at several NYCHA complexes across the city, including mold, pests, service outages and public safety issues.

Friday Sept. 2: New York City Mayor Eric Adams distributes bottled water to residents after 10 p.m., though the public was not yet aware the water supply at Jacob Riis was contaminated with arsenic.

Friday Sept. 2: After 11 p.m., city officials warn residents not to drink or cook with the tap water because it had tested positive for arsenic. The City reports that officials had known about the arsenic for two weeks.

Saturday Sept. 3: At an emergency meeting, residents express outrage that they had been kept in the dark about the water conditions.

Saturday Sept. 3: Manhattan Borough President Mark Levine assures East Village residents there is no evidence of arsenic contamination in the surrounding neighborhood.

Saturday Sept. 3: The federal monitor appointed to oversee NYCHA in 2016, Bart Schwartz, announces a probe into the water conditions.

Sunday Sept. 4: Officials release results of water tests conducted a day prior that showed no elevated arsenic levels.

Monday Sept. 5: Additional testing finds no arsenic, though the mayor’s office still advises residents not to use the water as it awaits test results on 100 additional samples. City officials speculate that the plumbing system, rather than the water supply, could be the source of the contaminant. The initial positive tests were taken at high-rise buildings where the water is routed to a roof tank; the new negative samples were taken from low-rise buildings.

Monday Sept. 5: Residents are instructed to help flush out the system by letting their faucets run for three hours at a time on three consecutive floors.

Monday Sept. 5: The federal monitor orders the city to preserve all documents related to the water quality issues at the complex.

Thursday Sept. 8: City officials said subsequent tests showed Legionella – the bacteria that causes Legionnaires Disease – in the water, but cast doubt on the findings, both because no cases of the disease had been detected at the complex and Legionella cannot be spread through drinking water. 

Saturday Sept. 10: Adams declares the water at the housing complex was never unsafe to drink and blames Illinois-based Environmental Monitoring and Technologies for introducing arsenic into the samples.