[MUD_Wizard]

Originally Posted by Sephiroth

You can say that if, without re-segmentation, they add downstream capacity such that the additional downstream channels are not pinched from an existing set, then at the instant of cut over to the new system, downstream congestion would be halved.

They would be pinched from an existing set though, most likely.

It really depends whether it's just one node that is over-utilised or more than one node in the area.

Also the amount of over-saturation. If one drain gets clogged rain will flow into another nearby drain, but once all drains are maxed out the water has nowhere to go.