The wash enters the center-west bank of Lake Havasu on the California–Arizona border.

The 35-mile (56 km) long Chemehuevi Wash drains the center of Chemehuevi Valley; it begins southwest of the center of the Sacramento Mountains, with the water divide separating the northwest draining Ward Valley, a southwest tributary to the Piute Wash region west and northwest of Needles.

The Chemehuevi Wash and Valley drain southeasterly, then turn due east for about 12 miles.

The Chemehuevi Wash and Valley are about 15 miles (24 km) wide and the change in direction of the drainage to due east to meet the west shore of Lake Havasu is caused by the blocks of mountains, the Turtle Mountains southwest, and the Whipple Mountains southeast; the large Whipple massif is also the cause of the change in the due-south course of the Colorado River changing from southeast, back to southwest.

The Colorado River then continues mostly south, but again makes other turns before reaching the north of the Gulf of California.