After hearing, the Board may make a written order requiring the corporation to construct or maintain in good repair such fence, cattle guard, or farm crossing, or to make or alter such watercourse or ditch, or to remove such impediment to the same, within such time as it may fix. Such corporation shall not be required to open a ditch while the ground is frozen, nor to alter the natural course of or do any act in regard to a watercourse which it is not legally bound to do, nor to comply with such order until ten days after being served with a copy thereof. (Amended 1959, No. 329 (Adj. Sess.), § 39(b), eff. March 1, 1961.)