Push the box to the right until you see the platform above. Jump over the box and climb up the ladder. Pull the platform all the way to the right. Climb down the ladder and make sure the box is positioned close to the left-hand side of the gap in the platform above. If it is, pull the lever next to the ladder and the room will start to fill with water.
Climb up the ladder and jump to the box, when the water level is high enough, jump from the box to a second ladder on the left-hand wall. At the top, run into the alcove on the right and pull out a second box. Jump on this and when the water rises, jump up to the next platform.
Run to the left and slide down the slope, jump for the lower platform and pull the handle to open the platform up a bit. When the balloon pops out of the water, quickly shut the platform behind it and then roll it over to the right side and position it beneath the wooden section of the top platform. Climb the ladder to the top platform and stand on the wooden section. As the water raises so will you. Jump up to the higher platform when able.
Continue up the hill; pull the lever to the right of the ladder. This will fill the hole above you with water, causing the crate to float, once the water has stopped gushing in; pull the lever a second time. Climb the ladder and jump to the crate and across to the middle platform with a second lever. Pull this lever to bring down a large block to increase the water level, use this and the nearby crate to jump across to the upper platform.
After all of that jumping and lever pulling, its time for a quick breather! When you are ready, continue to the right.