The river flows generally west and northwest and then west again, joined by 21 tributaries including the Mackintosh, Murchison, Marionoak, Ring, Wilson, Stitt, Huskisson, Stanley, Heemskirk, Paradise, Owen Meredith, Savage, Whyte and Donaldson rivers before emptying into Hardwicke Bay and reaching its mouth in the Southern Ocean.

[2] The river is impounded at Bastyan by the Bastyan Dam (and adjacent hydroelectric power station) to form Lake Rosebury; and at Reece by the Reece Dam (and adjacent hydroelectric power station) to form Lake Pieman.

The construction of the power development scheme also altered the route of the Emu Bay Railway, and submerged a variety of rail heritage sites in the vicinity of the river, notably parts of the Wee Georgie Wood Railway or North Farrell Tramway line.

[6] The once-common suggestion that the river's English name comes from a convict "The Pieman" Alexander Pearce who was responsible for one of the few recorded instances of cannibalism in Australia, is not correct.

After a long series of offences in the colony, he was sent to the Macquarie Harbour Penal Station in 1822 but subsequently escaped, and was recaptured near the mouth of the river which now bears his nickname.