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2017 Map of O'Sullivan Dam

Name: 2017 Topographic Map of O'Sullivan Dam
Creator: U.S. Geological Survey
Published: 2017
License: https://creativecommons.org/publicdomain/mark/1.0/

USGS Topo · Published 2017

About this map

O'Sullivan Dam serves as the massive anchor for this landscape, holding back the waters of the Potholes Reservoir at the northern edge of the survey. The terrain is defined by the sharp transition from the elevated heights of the Frenchman Hills down to the agricultural expanse of the Royal Slope. This descent is marked by a complex series of basalt coulees and potholes that have been filled by the Columbia Basin Project's irrigation return flows.

A chain of water bodies, including Upper Goose Lake, Lower Goose Lake, and Blythe Lake, follows the path of the Goose Lake Wasteway. This drainage network ultimately feeds into Lower Crab Creek as it winds toward the boundary between Grant Co and Adams Co. The southern portion of the map reveals a rural grid of roads like W McManamon Rd and W Herman Rd, providing access to the wetlands and lakes that characterize this unique geological depression.