The state highway commissioner is hereby invested with full charge and control over roads heretofore or hereafter built or maintained by the state; and shall have the same authority to purchase or condemn land for highway purposes including lands containing gravel, stone or other material used and useful in highway construction as is or may be granted by law to township highway commissioners and to county road commissioners. The procedure that is, or may be, prescribed for condemnation proceedings instituted by boards of county road commissioners, is hereby expressly made applicable to such a proceeding when brought by the state highway commissioner. Such right of purchase or condemnation shall be deemed to exist in the case of the construction or maintenance of any road built or improved solely by the state, or by the state with federal aid, or by the state in conjunction with any of the municipalities of the state. The said commissioner may also exercise the same measure of authority as is or may be granted to county road commissioners with respect to the construction of drains when necessary for the construction or improvement of any highway within the contemplation hereof.