The flooding of Gotham City was an event cause by The Riddler’s van bombs.
Background[]
After murdering multiple of Gotham elite including mayor Mitchell,Commissioner Savage,Gil Coulson and mob boss Carmine Falcone, Riddler plans to get revenge on Gotham by flooding the city,to achieve this he parks several vans around Gotham’s sea walls and on the night of the 5th November when Bella Reál’s election rally is taking place, they will go off causing heavy damage and many casualties.
Flooding[]
Batman and officer Martinez whilst in Nashton’s flat discover his plan to flood Gotham by blowing the sea walls while watching a video of him.As the same time the vans blow causing rapid flooding, multiple deaths and casualties instantly.
With the water engulfing many buildings and destroying them ,evacuation would not be enough in a panic Gotham Square Garden is used for citizens to be safe despite the building usually used for a hurricane and not for the whole sea wall being destroyed.
Aftermath[]
Knowing that he will arrest for his crimes Nashton instructs his followers to assassinate Mayoral candidate Bella Reál at her rally in Gotham Square Garden, this eventually lead to a confrontation between the Riddler’s followers and the Batman which leads to the Knight night defeating them.
Some time later Gotham Square Garden is used for Gotham’s citizens to be evacuated and to receive medical treatment. The city is put under martial law and Gotham’s criminal underworld used the opportunity to loot damage buildings and terrorise areas where the authorities can’t get get to.The national guard is called in to assist, with the vigilant known as the Batman helping where he can.