The Townsend's vole is a large vole with large ears that extend above the fur, a long brownish or blackish tail and brownish or blackish feet equipped with brown claws.

In Oregon, it has been found along the Pacific Coast south to southern Coos County, throughout the Willamette Valley with eastward extensions along the Columbia River to near Hood River; the McKenzie River to Douglas County; and the Rogue River to Prospect, Jackson County. With few exceptions, Townsend's vole is associated with moist habitats: meadows, lowland pastures, riparian zones, boggy lands, marshes, and irrigated fields densely vegetated with grasses and sedges.

It is active t throughout the year and thought the diel cycle. It readily enters the water and is a good swimmer and diver. These voles construct and use a complex system of runways. Nests of grasses are constructed above ground on hummocks in winter but below ground in summer.