Here they dropped distribution pressures because there has been zero pipeline maintenance in the system aside from repair as it fails and some small sections ( with the largest leaks) being replaced with HDPE pull in place piping. This was to reduce the non metered loss from 50% to 30%, as basically every pipe leaks, every tap point is rotted near to nothing and the valve stem seals are often a century past the replace by date.
One reason I put in a 0.2 micron filter is this, as the regular daily water cut off scours the piping system, depositing all the asbestos mud into the water as it scours the pipes coming back to full, and I do not want to drink that sludge. Filters go brown pretty fast even without this scouring, there is a lot of sediment and junk in those century old pipes, that has accumulated through the years as sections were replaced and mud got into the system. Still has lead pipes in places, and a lot of the copper piping was lead soldered.
The pull in place was done so there was no need to remove and dispose of asbestos cement pipe, just hydraulic crack it with the tunnelling machine as the new pipe is pulled through the bore, and then cut down at each customer tap and drill into the pipe with a clamp on tap. They just marked all the fire hydrants in the affected areas with a blue painted top to indicate the presence of the HDPE pipe, so the fire brigade knows there is a lower maximum flow rate available on these points, as there is a smaller 4 inch pipe instead of the old 6 inch fibre cement pipe.
As to sprinkler systems, there are multiple reasons for installing them, either the height of the building, the occupancy profile or what is stored or manufactured there. Whatever the reason, you will have the same arrangement, a Christmas tree ( or a few on larger buildings, which is the name for the control block that does flow detection, alarm activation of the water bell, non return valving and a booster connection along with a draw point into the large water mains) that pressurises the piping, the pipe tree and isolation valves to shut the parts off for maintenance, so you can do service a floor at a time and still have the system armed, the pipes into each section ( always exposed red painted steel pipe, with clamped sections for easy pipe section replacement) and finally the sprinkler heads, with the detector element ( either fusible metal block or glass frangible plug) and a spray nozzle in there to act as control units.
Larger buildings you will have either a small header tank on the roof to provide back up pressure so there is water in the system long enough for the fire brigade to arrive and provide boost water pressure, and in some cases large tanks on the property and boost pumps as well, either electric with a backup generator or simple diesel pumps alone.
At the very least the building should have has hose reels per floor, with hose pipe at the regulatory 30m length, and such that any 2 can be used on any fire. that these were either not there, or not working, is a direct reflection on the building owners, as this is a part they are required to maintain.