When the city governing board determines that there is a surplus in the municipal utilities fund over and above any amount necessary to provide adequately for the operation and maintenance of the utility, it may transfer from the surplus in the fund to the general fund or to any other fund a total sum of not more than twenty percent of the gross receipts of the municipal utilities for the fiscal year during which the transfer is made. So, for example, if a city had $500,000 in gross receipts to the utility fund for the year, they could transfer twenty percent ($100,000) to the general fund by motion of the governing body provided the utility fund had that much in surplus. A larger amount may be transferred upon resolution of the governing body and approval by the voters at a regular city election. (NDCC 40-30-12)