FLINT, MI - It could take up to 15 years and more than $60 million to replace lead water service lines in Flint, according to emails released by Gov. Rick Snyder.

A Sept. 28, 2015, briefing sent to the governor detailed the cost and timeline associated with replacing the more than 15,000 lead service lines in the city.

"Even if many crews were contracted, it would likely take up to 15 years to complete this work," the briefing reads.

There are less than 33,000 total service connections in the city.

The average cost to replace a lead service line at an individual home costs $2,000-$8,000, the briefing claims.

The Wednesday, Jan. 20, release includes 274 pages of documents, including communications on Flint water issues, public safety and lawsuits. However, only seven emails sent by Snyder on the city's water system were included in the distribution.

Many of the documents included previously-distributed press releases, talking points and studies.

The release of the emails comes after repeated calls from the MLive Media Group and others for Snyder to make all of his communications on Flint water public.

Emails from Snyder's office are exempt from the state's Freedom of Information Act.

The release, which the governor's office says all emails he sent and received regarding Flint from January 2014 through December 2015, comes the same day Snyder appealed President Barack Obama's decision denying a federal disaster declaration for Flint's water crisis.

Obama signed an emergency declaration Jan. 16 ordering federal assistance after some of the city's youngest residents were diagnosed with elevated blood lead levels following the switch to the Flint River as the city's drinking water source.

The appeal is seeking an unspecified amount of federal assistance to address long-term health threats, damage to the city's infrastructure and economic damage the city is experiencing during the crisis.