There are complaints about notification, but Ameren says it used its normal notification process.
Ameren plans to shut off power to some businesses and residences to make improvements to its power system.
Due to safety concerns, Ameren's policy is to only tell customers who would be affected.
Customers have told us the power outage will take place from 4:30 to 8:30 Sunday morning and will affect an area of downtown.
Many customers have said they are upset by the little notification from the utility.
However, Ameren has told us that it started calling customers as early as six days ago.
Ameren Spokesperson Stacey Shangraw said, "We have a list of customers that are impacted by that outage, and we have been calling the residential customers since yesterday, and the business customers have been notified everywhere from six days ago until now."
The improvements are part of a 7-million dollar project that will go toward enhancing the safety and reliability of the power system.
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