FLINT, MI - EPA officials issued a letter saying they are worried about Flint's neglect to stock enough chlorine tablets to treat the city's water.

In a letter stamped July 19, EPA officials said the City of Flint ran out of chlorine tablets which help treat water for various bacteria.

JoLisa McDay, interim utilities administrator in Flint.

"We were very concerned to learn that on Friday. July 16 the City ran out of chlorine tablets for the pellet chlorinators, resulting in an additional chlorination being available at either of Flint's reservoirs," said the letter. It went on to say that after EPA officials contacted Flint, City officials did "take steps to increase chlorine addition at the plant and to obtain chlorine pellets on an emergency basis."

City of Flint Interim Utilities Director, JoLisa McDay said, "the facility always maintained supplies of chlorine on site to be administered to drinking water as needed."

A statement issued by Flint Spokeswoman, Kristin Moore, also said the city had other things in place outside of chlorine tablets if needed.

"While there may not have been chlorine tablets on hand..there was always bleach on hand in liquid form that could be administered if needed," said Moore. "Therefore, there was no danger present to public health..There was no lapse in operation for the chlorine system at the (water treatment plant.)"

Moore said the water plant was transitioning from calcium hypochlorite pellets to sodium hypochlorite which is used in larger cities similar to Flint and is "more efficient" than the calcium hypochlorite tablets.

In June, EPA had directed the city to add the new equipment to boost the level of chlorine in the city's water warning that the situation was "urgent" with the summer weather.

Chlorine is a disinfectant used to protect water systems from bacteria, including Legionella, which can lead to Legionnaires' disease and a flu-like illness called Pontiac fever.

Officials have been investigating a possible link between an outbreak of Legionnaire's Disease and a catastrophic switch of the city's water supply to the Flint River. The water was switched back to a Detroit feed after it was discovered that river water had corroded pipes and caused high lead levels in homes around the city.

Since the lead crisis, the EPA has been closely monitoring the city's water operations.

"While the City is moving toward an appropriate change in chlorination systems as the reservoirs, the City cannot lose capacity to add chlorine at the reservoirs before the new chlorine feed systems become operational," the letter said. "The lapse in ability to add chlorine at the reservoirs, and the fact that no action to secure pellets appear to have been taken until EPA elevated the issue and MDEQ intervened, demonstrate a continuing need for the City to take stronger action to effectively manage the drinking water system."

The letter was sent to Weaver and MDEQ officials.