The Great Lakes are one of the world's largest sources of fresh water, but many Americans in surrounding cities face a dark irony: They can't afford their rising water bills.

Northern Indiana Public Service Co. serves about 820,000 natural gas customers and 460,000 electric customers across 32 counties.

Vectren, which serves a significant portion of central and southern Indiana, has had some of the highest rates in the state. The merger with Houston-based CenterPoint Energy will not reduce rates immediately.

Indianapolis Power and Light seeks a rate hike to cover higher operating and maintenance costs and to cover the costs of the newly built Eagle Valley Generating Station in Morgan County.

The Indiana Utility Regulatory Commission plans April 23 and May 7 public hearings on the proposals that could raise its residential power rates about 10 percent.

While rates have been on the rise, the Hoosier state is burning less coal for electricity. Coal accounted for 65 percent of the fuel used for electricity in 2016, down from 85 percent in 2007.

The program is open to many whose household income is below 150 percent of the federal poverty level.