Full list of all 70 PowerWash Simulator achievements. It takes around 35-40 hours to unlock all of the achievements in the base game on Windows.
The base game contains 40 achievements, and there are 3 DLC packs containing 30 achievements.
Complete the Conch Street job
Complete the Bikini Bottom Bus job
Complete the Krusty Krab job
Complete the Patty Wagon job
Complete the Invisible Boatmobile job
Complete the Mermalair job
In the Conch Street job, complete Patrick's Rock, Rock Hinge and Rock Underside last
In the Krusty Krab job, complete the Chum Bucket first
In the Patty Wagon job, complete the Pickles first
In the Mermalair job, complete Patrick's Identity Card first
Complete the Doc Brown's Van job
Complete the Time Machine job
Complete the Clocktower job
Complete the Holomax Theater job
Complete the Doc's Time Train job
Watch the Time Machine reappear
In the Clocktower job, ring the bell
In the Holomax Theater Job, activate the holographic shark
In the Holomax Theater job, clean the Grid Wall first
In the Doc's Time Train job, clean the Flux Capacitor and its Particle Colliders first
Complete the Land Raider job
Complete the Redemptor Dreadnought job
Complete the Rogal Dorn Battle Tank job
Complete the Imperial Knight Paladin job
Complete the Thunderhawk job
In the Land Raider job, complete the "Ultramarines II" Plaque first
Completely clean the Redemptor Dreadnought using only the yellow nozzle
In the Imperial Knight Paladin job, complete the Tilt Shield and Tilt Shield Purity Seals first
In the Rogal Dorn Battle Tank job, complete the Stowed Shovel first
In the Thunderhawk Job, complete the Retro Thrusters first