The latest round of work on the Lake Decatur dam is underway and will include a barrier aimed at keeping invasive Asian carp at bay.
The $4 million project is set to be finished by fall 2014.
The (Decatur) Herald & Review reports the first phase of the project was completed in 2011.
The latest round of work includes fixing concrete and repairing erosion damage. Meanwhile, crews will also remove a failed tailwater dam, which was built more than a century ago.
Keith Alexander is director of water management in Decatur.
He says replacing the entire Lake Decatur dam would cost more than $60 million, so it's more cost-efficient for crews to do "preventative maintenance" work every five to 15 years.