If, in the opinion of the budget-making authority, such reserve fund is insufficient to meet the cost of any capital or nonrecurring expenditure, property tax revaluation or plan of conservation and development which it deems immediately necessary, it may, with the approval of the legislative body, authorize that an appropriation be made therefor, provided the total of such fund and the sum anticipated from a tax collected for the purposes of sections 7-360 to 7-364, inclusive, in the year following the date when such authorization is made is estimated by said budget-making authority to be sufficient to meet such expenditures. Nothing in said sections shall prohibit a municipality from supplementing said reserve fund to meet the cost of capital or nonrecurring expenditures, property tax revaluation or plan of conservation and development by issuing bonds in accordance with the applicable provisions of the statutes.