Oil Trough residents are asking the Army Corp. Of Engineers for an impact study relating to flooding. In April, the city had its worst case of flooding in 22 years. Officials say the White River crested at 35 feet, just 4.5 feet lower than it did in 1982. Residents say levees placed near the river banks disrupted the flow of the river, causing water to back up into their homes and businesses. Corp. officials say it could take weeks to determine whether a study is needed and could cost at least $7 million to fund.