Is it just me, but if there’s enough drainage send a train with hundreds of ice blocks, drop them off in alcoves along the tube tunnel and they’ll melt absorbin

Is it just me, but if there’s enough drainage send a train with hundreds of ice blocks, drop them off in alcoves along the tube tunnel and they’ll melt absorbing large amounts of heat. Maybe not 500 GW I grant you, and water and electricity need to be kept well apart, but sure some areas could be isolated. I’m guessing drainage is an issue, but there’s always a risk of flooding I would have thought there would be drains and pumps already there.