The addition, costing between $200,000 and $250,000, was endorsed by councillors on the second day of the DCC's annual plan hearing on Thursday.
Council waste and environmental solutions group manager Chris Henderson said all customers would have their vehicles weighed when entering and leaving, to calculate the weight of their rubbish loads.
Staff could charge by weight, rather than applying an average cost per vehicle type, which would reduce the fee for many customers.
It would also eliminate a source of friction between customers and staff at the pay booth, he said.
Councillors endorsed the move on Thursday, including Cr Lee Vandervis, who was swayed by arguments it would be fairer for customers.
Cr Jim O'Malley said it was a "no brainer" that would encourage people to recycle and remove "guessing" over the charges.
