This is an overnight walk from Ormiston Gorge in Tjoritja / West MacDonnell National Park in the Northern Territory. Part of the route is on the Pound Walk from Ormiston Gorge, and the remainder is along Ormiston Creek.
The official Ormiston Gorge overnight walks guide suggests that you leave the Pound Walk at the first creek crossing after exiting the gorge itself, but I decided to just follow the track until the final creek crossing. Walking in and along the creek is noticeably slower than following the track as there's quite a bit of boulder-hopping and sand to walk through, so leaving the track earlier may actually be e good idea.
The campsites at Bowmans Gap are situated on the northern side of the gap. Note that you need an NT parks pass, and the Bowmans Gap campsites are on the NT parks campsite booking site, so you don't need a remote camping permit. There are no facilities at Bowmans Gap, but there are plenty of sandy campsites.
Depending on recent rainfall, you may be able to get water at several waterholes along the way and at Bowmans Gap itself. I recommend starting the walk with enough water for a complete return trip in case there's no acceptable water available along the way. It's unlikely that you will find flowing water — it will almost certainly be in waterholes filled from recent rainfall events, so treat it appropriately.