1. You begin at this firefight.
2. Don't bother participating in the firefight. Instead, run down the road in this direction.
3. Enter through this open door and the unlocked gate beyond.
4. Ascend the stairs to the top floor. Exploring other floors is pointless as they all dead-end.
5. Pass through this unlocked gate then continue through the doorway at the end of the hall.
6. Once in this room you'll spot that hole in the wall. Crawl through and drop to a ledge outside.
7. Climb the two ladder-like pipes on the right then follow the beam to an air vent.
8. Ready your Colt M4 then drop through the vent to battle these two, plus a third above.
9. A medium medkit is in thorugh the first doorway and armor is through the second.
10. Pass through those blue doors and battle two patrols beyond.
11. Fight your way up these stairs.
12. Defeat three guards - two are equipped with McMillan M87Rs - before descending the ladder at the end of the hallway.
13. Step onto the balcony and battle these three in the next room.
14. Grab the large medkit from the cabinet seen on the left before descending the ladder seen on the right.
15. Defeat these three before grabbing the armor from the cabinet on the far-right wall.
16. The balcony affords a view of the firefight you left at the beginning of the level.
17. Drop to the floor below. If you are lucky you can take out this patrol two floors down.
18. Defeat these four before descending the stairs.
19. You'll find an armor vest hidden back here.
20. Descend the nearby stairs to the lower level. Defeat these two and grab the armor from a cabinet behind them.
21. Ready for a major battle as you pass through these doors.
22. Clear out the opposition before descending the ladder seen on the right.
23. More of the same down here. Clear out the area then approach the nearby stairs.
24. Before descending the stairs you'd be well advised to snipe this patrol waiting at the bottom.
25. Clear the area then grab the large medkit from the cabinet visible far-right. Proceed through the door behind you.
26. Take out the lone patrol on the right before ascending the stairs to the left.
27. Advance through those blue doors on the left.
28. Two patrols and a cabinet with armor are ahead.
29. To the left you'll find more resistance below. Descend the stairs.
30. A cabinet by the stairs holds armor. Defeat these two before climbing the ladder ahead.
31. Here's the welcoming committee when you reach the top.
32. This is a tough area to clear -- more guards will pour in from upstairs.
33. On the upper level you'll find another guard behind the grating on the right. Hop through the vent on the left.
34. There are two guards to defeat here. Grab armor from the cabinet and descend the stairs.
35. Clear the area then descend this ladder on the left. Ignore the door visible on the right for now.
36. After a small battle you can grab the large medkit from the cabinet seen on the left.
37. Rotate this pipe to stop the leaking steam on the level above.
38. Backtrack up the ladder, past the broken (but no longer steaming) pipe, then prepare for a battle as you open the blue doors ahead.
39. You'll find this guard just inside the door, plus three more popping up from behind these barricades.
40. A fifth is waiting in ambush here.
41. Through yet another blue door you can see your reward up ahead - a cabinet with armor. Jump over the broken railing in front of the cabinet to the crates below.
42. You'll find this medkit here.
43. Proceed down this ladder.
44. You'll battle these three guards, plus a forth up the stairs on the left. A large medkit is in a cabinet down the right corridor.
45. You'll find two guards and a cabinet with armor in this small room.
46. Follow the outer wall to this position, where you'll find three guards, including one just visible under the stairs.
47. Ascend the stairs, then take these stairs back down. Defeat the two guards then climb under the large door as indicated.
48. You'll find armor behind those crates. Ramp up the board to the level above.
49. Ramp up this board and follow the pipe.
50. Climb into the vent above.
51. Exit from the vent and clear out these three below.
52. Drop to the vent, then the pipe, then the stairs to the level below.
53. You'll find armor in the cabinet seen on the right.
54. Climb your last ladder of the level.
55. Defeat this guard then climb through the vent behind him.
56. Drop through this hole to the ledge, pipe, then stairs below.
57. Four guards are on the other side of this door - a good time for adrenaline mode.
58. Activate the indicated switch, then watch the three rods on the right rise into place. Once all three lights have turned from red to green, you're good to go.
59. Descend the stairs and continue past the formerly-steaming pipe. Your sniper rifle and/or adrenaline mode helps take out the three final guards of the level.
60. Once all three are down, descend that ladder visible rear-left.
61. You've found the barrels. Walk toward the end of this walkway to trigger the ending cutscene.
62. A firefight ensues.
63. But your comrades are unable to prevent the barrels from falling into the water, contaminating the waterworks.