The Pittsburgh Water and Sewer Authority announced Tuesday that it is now in compliance with Environmental Protection Agency standards for lead levels in drinking water.
PWSA tested tap water at 128 residences and found that the 90th percentile level was right at the EPA action level of 15 parts per billion. That means that less than 10 percent of homes were above 15 parts per billion.
The results of the testing were as follows:
- 45 homes had non-detectable levels of lead
- 25 homes were between 2.1 and 5 ppb
- 30 were between 5.1 and 10 ppb
- 16 were between 10.1 and 15 ppb
- 12 were above 15 ppb
“The goal is to be nonexistent or zero,” said PWSA interim executive director Bob Weimar.
After exceeding the action level last summer, PWSA is required to show that it is at or below 15 ppb for two consecutive rounds of testing. The next round of testing will take place in December.
Compliance testing from June 2016 showed a level of 22 ppb, which put PWSA in violation of the Safe Drinking Water Act. Tests in December 2016 showed the level had dropped to 18 ppb. Prior to last summer, compliance tests had not been performed since 2013, when the 90th percentile level came back at 14.8 ppb, just shy of the EPA action level.
“While the work on the issue by the City and the PWSA over the past year is clearly paying off, there is still a lot of work to do,” Peduto said.
Weimar said the drop in lead levels is due in part to improvements in corrosion control.
In 2014, while under the management of a company called Veolia, PWSA changed the chemical it uses to prevent corrosion in lead pipes, without authorization from the state. Many observers say it was that change, from soda ash to the cheaper caustic soda, that lead to the spike in lead levels two years later.
Weimar said PWSA is now using lime and soda ash for corrosion control, but has plans to change chemicals again.
“The intent is to use a phosphate-based compound which has been shown nationwide to have the highest degree of effectiveness in mitigating this type of corrosion,” Weimar said.
The 2016 exceedence triggered a clause in the Safe Drinking Water Act that requires the replacement of 7 percent of lead service lines per year. The authority and the city are now grappling with how to comply with that regulation. PWSA said state law bars it from replacing the private side of a water service line – from the curb to the house – at the same time it replaces the public side.
A bill that would allow the city, not the authority, to take over the task of replacing the private side is expected to be discussed in City Council this week.
A bill in Harrisburg that would have allowed any water authority to replace private lead service lines has passed the Senate but awaits action in the House.
In the meantime, the city has distributed 20,000 water pitchers that filter out lead, with an emphasis on vulnerable populations including pregnant women and households with small children.