2020 Map of Black John Coulee

About this map

Black John Coulee and several other deeply carved drainages define this Garfield County landscape, illustrating a complex hydraulic network in Montana's eastern plains. The map details the drainage patterns of Big Dry Cr and its tributaries, including Nelson Coulee and Russian Coulee, which flow through the arid terrain. The southern portion of the sheet is dominated by the winding course of Langs Fork, which carves through the township boundaries of T18N and T17N. This 2020 survey captures the region's topographical character, showing how seasonal water flow has shaped the coulees and creek beds across this sparsely populated section of the state. It provides a clear view of the relationship between the elevated plateaus and the low-lying Jones Cr basin, essential for understanding the local hydrology and land divisions in this part of the Missouri River watershed.