If the work in the office of the auditor by reason of the existence of drainage districts is so increased that the regular officer is unable by diligence to do the same, the board of supervisors may employ such additional help as may be necessary to keep the records and transact the business of the drainage districts. The expense of such help shall be paid by the districts in proportion to the amount of work done therefor.
89 Acts, ch 126, §2
CS89, §468.154