Whenever fifty or a majority of the holders of title to, or of evidence of title to land susceptible of "irrigation" desire to organize an irrigation district for any or all of the purposes mentioned in RCW 87.03.010 and 87.03.015, they may propose the organization of an irrigation district in the manner provided herein; and when so organized, such district shall have all the powers that may now or hereafter be conferred by law.