(4) Through the present day, the majority of the lands added to the reservation in 1909 remain inundated due in part to the flowage of natural runoff and drainage water from the irrigation systems of the Imperial, Coachella, and Mexicali Valleys into the Salton Sea.
(the majority of the lands; remain inundated; due; to the flowage of natural runoff and drainage water from the irrigation systems of the Imperial, Coachella, and Mexicali Valleys into the Salton Sea)
the majority of the lands
remain inundated
due to the flowage of natural runoff and drainage water from the irrigation systems of the Imperial, Coachella, and Mexicali Valleys into the Salton Sea