Is it merely an assumption that this is hydraulic fluid? When I first saw it, I thought they had turned on fire hoses to obstruct a potential shooter's line of sight. Additionally, if you observe closely, it appears to be spraying from two directions: the obvious one and another one directly opposite, 180 degrees across from the main spray. Notice that both produce an angled exit spray pattern, indicating that the fluid is being expelled from a small orifice at high pressure.
Is it merely an assumption that this is hydraulic fluid? When I first saw it, I thought they had turned on fire hoses to obstruct a potential shooter's line of sight. Additionally, if you observe closely, it appears to be spraying from two directions: the obvious one and another one directly opposite, 180 degrees across from the main spray. Notice that both produce an angled exit spray pattern, indicating that the fluid is being expelled from a small orifice at high pressure.