The board of drainage commissioners may open all natural drains which they deem necessary in their respective districts and perform all work connected therewith, which they may deem necessary to make the opening of the natural drains effective.  They may cut and open new drains, ditches, and canals wherever deemed necessary.  In order to carry out the drainage works, the drainage commissioners may enter into contracts for the performance of these works, or purchase machinery and have the work performed under their supervision, and perform all other acts necessary to fully drain all the land in their districts and maintain the drainage when established.