Hamilton’s drinking water is safe and well-monitored, this is the take-away from the 2020 Annual Drinking Water Report released at the end of February as required by Ontario Regulation 170/03.
The City maintained full testing of the distribution system during 2020, with only in-home lead testing suspended due to COVID.
This lead testing requires staff to enter into homes to get samples. The City increased testing in its Lead Pipe Loops to compensate.
“Plumbing samples provide water quality data as seen at the residential taps that have service lines which are known or suspected to contain lead. Without this sampling data, the City of Hamilton loses one source to observe the effectiveness of the Corrosion Control Program (CCP)”, wrote Andrew Grice, Director of Hamilton Water, in response to TPR questions. “As part of the CCP, the City of Hamilton installed three pipe loops with confirmed lead services, as an additional data set for monitoring and observing the effectiveness of the CCP”.
In 2018, the City added orthophosphate to treated water to prevent corrosion of metal pipes, especially old lead pipes which nearly 20,000 Hamilton homes continue to have on the private property portion of their water service.
2020 testing shows ead levels in the water system continues to decrease, including at the three pipe loops.
Hamilton’s water supply is constantly tested from the intake pipe in Lake Ontario to the further reaches of the system. During 2020, there were 15 events of what is termed an “adverse water quality incident” which occurs when any test does not meet strict quality standards. Ontario’s standards are very strict, and reports of adverse findings made public, following the Walkerton water disaster.
The detection of any coliform, as an example, triggers a report. Most of the adverse findings were not confirmed with nearby water samples.
Chlorine levels are required to be above a minimum threshold. When those thresholds are not met, it triggers a flushing of that section of the water system to restore chlorine levels, increased monitoring, and detailed reporting.
COVID-19’s closure of schools, businesses, and many institutional uses changed water flow patterns. Chlorine disinfectant dissipates over time, and with lowered water usage in some parts of the system resulting from COVID, this is a concern Hamilton Water is monitoring.
Thus far, Hamilton Water has only found one area of the system where this is was a concern. [Hamilton’s water distribution system is highly interconnected which improves its resiliency and minimizes impacts of demand changes.]
The sampling station across from 31 Currie Street, in the East Mountain Berrisfield neighbourhood, is along a section of pipe which services multiple schools, including the Barton Secondary School building.
Grice states that COVID closures is a likely cause for the decreased water flow in this section, and the most likely reason for the decreased chlorine counts found in September and October.
“The flow dynamics in the water distribution system near Currie St during COVID-19 may have been reduced due to a decrease in water consumption by industrial, commercial and instructional facilities in the area”, Grace wrote in response to questions.
”Hamilton Water installed an auto flushing unit on Currie St to improve water circulation within the water distribution system. After installing the auto flushing unit we have seen no concerns with the water quality in the area”.
In 2020, one of the repeated locations of coliform detection was likely the result of an old fixture/tap which the water samples were taken from at the City of Hamilton Operations Yard at 308 Rymal Rd East.
Coliforms were repeatedly found in the water samples at this location, until the tap was replaced. At which point, repeated and routine sampling did not detect coliforms.
Ontario’s Ministry of Environment and Climate Change conducts extensive inspections of Hamilton’s water system. The 2020-2021 inspection was underway when the 2020 annual report was published.
EDITORS NOTE:
Hamilton Water Director Andrew Grice was very forthcoming with reports and data. The Public Record requested and received detailed lead testing information, including individual result reports. Further, requests for water flow information related to COVID changes were provided quickly with great detail. Emily Trotta, who has taken over communications for the Public Works department during COVID, was very helpful in assisting to facilitate the transfer of data.