The annual operation and maintenance budget shall include provisions for accumulation of a reserve fund for extraordinary maintenance or operation. The amount budgeted each year for the reserve fund shall be at least ten percent of the estimated cost of the annual routine operation and maintenance. Annual increments for the reserve fund shall be budgeted whenever the balance in the accumulated reserve fund is less than the current annual operation and maintenance budget. Expenditures from the reserve fund may be made by the managers whenever, in their judgment, extraordinary operation or maintenance of the project works is necessary.
SDCL 46A-14-67