Wooster City Council has approved legislation to find a contractor to replace key components in the wastewater treatment plant.   The project is part of a larger effort to renovate the aging water infrastructure at the facility.  The estimated cost to make the needed upgrades at the facility increased by nearly $900,000 from $1.8 million to $2.7 million, largely due to inflation, according to the city.  Despite the increase, users will not see any rate increases as the city will foot the bill from its sanitary sewer budget and bonds to cover the extra expense.