Less than two weeks after residents complained about high chlorine levels, the water provider for much of Collin County and the surrounding area said it met "regulatory standards."

The North Texas Municipal Water District released test results from throughout its system on Thursday afternoon. At all dozen testing location, the chlorine levels continued to fall below the federally set annual average of 4 parts per million. Some exceeded that number just slightly during its recently finished 28-day chlorine "maintenance" period but still met Environmental Protection Agency rules.

Some residents had recently complained about the smell and taste of the water. And some questioned if their rashes and other health problems were due to the water quality. The issue received a lot more attention after famed environmental activist Erin Brockovich publicly criticized Plano's water quality in a lengthy post on Facebook this month.

"Water provided by NTMWD is safe and meets all state and federal water guidelines," said Tom Kula, the district's executive director, in a written statement. "The chlorine maintenance process is backed by science and is a proven way to help safeguard public health."

Each year, just before spring, the water district uses plain chlorine as a disinfectant to address and prevent build up inside its pipes. The utility uses a combination of chlorine and ammonia the rest of the year.

While that's a common practice, Brockovich raised concerns about whether that's a safe or effective approach. She said on Facebook that the chlorine "burn," as its often called, meant that the utility has lost control of its water quality and said online that chlorine levels should not be near the federal limit.

Brockovich initially targeted Plano water. But that city, along with dozens of others, get their water from the North Texas Municipal Water District. That agency provides water to nearly 1.7 million people in the region.

This routine chlorine procedure, which the district has been using for a decade, was largely ignored by the public until Brockovich's intervention. Since then, a 12,000-member Facebook group called Safer Water, North Texas has formed to share information and put pressure on the North Texas Municipal Water District and local cities.

Much of the criticism has surrounded the smell, taste and perceived health issues from the chlorine procedure.

Brockovich has generally been more critical of the combination of chlorine and ammonia, known as chloramine. That's used to reduce dangerous disinfectant byproducts produced when chlorine alone is used. But experts say there is limited research into the health effects of byproducts caused by chloramine.

Brockovich and water consultant Bob Bowcock are scheduled to speak to concerned residents at 6 p.m. Thursday at Frisco Celebration Hall. Tickets are being initially offered for $10 to Safer Water, North Texas Facebook group members. The general admission tickets would be available later at $20.