In Dying Light: The Beast, the Hydro-Puzzle side quest takes you on a mission to fix the city’s water problems and uncover some hidden treasures along the way. This guide will show you how to start the quest, navigate the Water Repairs Facility, and find the safe in the office that holds valuable items and the key to the Chief Engineer’s Office.
How to start the Hydro-Puzzle Quest

You can unlock the Hydro-Puzzle side quest after finishing the main story quest Power Gambit in Dying Light: The Beast. Once you’ve activated the first Relay Station (you’ll find it just east of the Town Hall), Pietro will contact you over the comms asking for help. If you head over to the Old Villa area, Pietro will mention some problems with the water supply and ask Kyle to check it out. From there, your next stop will be the Water Pumping Station.
Hydro Puzzle Safe – Office Key Location


Make your way to the Water Repairs Facility and find a way inside. You can climb the scaffolding on the side of the building to reach the terrace, where there’s an open-air duct you can crawl through. Once inside, take care of any infected you encounter and keep moving forward until you reach a small office with a Sage inside.
The safe there opens with the combination 27-1-15, and inside you’ll find some valuable items ( Military Medkit) along with a key to the Chief Engineer’s Office. There will be lots of zombies inside, so be careful and have a lot of ammo and your weapon ready.
To know all the safe codes in Dying Light: The Beast, read our article on “All Safe Codes, Combinations & Locations – Dying Light: The Beast”