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2023 Map of O'Sullivan Dam

Name: 2023 Topographic Map of O'Sullivan Dam
Creator: U.S. Geological Survey
Published: 2023
License: https://creativecommons.org/publicdomain/mark/1.0/

USGS Topo · Published 2023

About this map

Potholes Reservoir dominates the northern horizon of this central Washington landscape, where the high desert meets a complex network of man-made irrigation and natural drainages. South of the dam, the terrain rises sharply into the Frenchman Hills, a prominent basalt ridge that overlooks the agricultural expanse of the Royal Slope. This area is defined by the massive infrastructure of the Columbia Basin Project, evidenced by the Potholes Canal and West Canal, which distribute water across the arid plateau.

Much of the eastern and southern portions of the map are preserved within the Columbia National Wildlife Refuge, a rugged territory of coulees and lakes including Corral Lake, Black Lake, and the winding Lower Crab Creek. Small settlements like Marine View sit near the reservoir's edge, while the southern boundary follows the Crab Creek Lateral and the Grant-Adams county line. The map illustrates a unique hydrosocial landscape where historic watercourses like Deadman Lake are integrated into modern water management systems.