[1] The creek continues generally northeast until it becomes a tributary of the Beaver River (North Canadian River) in Oklahoma at a point east-northeast of Hardesty, Oklahoma, west of Balko, Oklahoma, and north of U.S. Route 412 near the Texas County/Beaver County line, downstream from the Optima Lake project.

[2] North Palo Duro Creek in turn originates at about the Dallam County/Hartley County line east of Dalhart and west of Cactus in Texas.

[3] South Palo Duro Creek originates east of the Hartley County/Moore County line, west-northwest of Dumas, Texas.

[6] The reservoir was created for both water supply and recreation purposes.

[6] But the reservoir has never reached more than a few percent of its capacity: both the creek and reservoir rely on surface runoff to fill, in an area with little rainfall and prone to drought.