A unified municipality shall succeed to all the assets and liabilities of the municipalities it unified. A bonded indebtedness or other debt incurred before unification remains the tax obligation of the area that contracted the debt, except that by ordinance the tax obligation may be assumed by a larger area if the governing body determines that the asset for which the bonded indebtedness or other debt was incurred benefited the larger area before unification, or benefits the larger area after unification. However, bonded indebtedness or other debt for sewage collection systems, water distribution systems, and streets, even if determined to be benefiting a larger area than that which incurred the debt, remains the tax obligation of the area that incurred the debt.