A proposed increase in Ameren natural gas rates would affect parts of the Quad-Cities.

Ameren Illinois has filed the request with the Illinois Commerce Commission, stating the rate increase is needed to recover the costs of infrastructure investments and to compensate for increased costs of delivering natural gas to customers, according to a company news release.

If the company were granted the full amount it seeks, the increase would amount to an additional $50 million for Ameren. That would translate into monthly increases for customers of about $2.52, $2.87 or $4, depending on where they live and the amount of natural gas they use.

Ameren covers parts of Rock Island and Henry counties and all of Mercer County, said an Ameren spokeswoman. Customers in those areas could expect to see a $2.87 increase.

The ICC is reviewing the request, a process expected to take about 11 months.

The Citizen's Utility Board has issued a release stating it will monitor the rate hike request and argue against any portions of the increase it deems unnecessary.