According to reports, Southampton Central station has flooded due to a leak, diverting all trains away from the station.
Trains are being diverted to Chandler's Ford, with disruption expected to last all day.
South Western Railway tweeted: 'Due to water leaking onto the railway at Southampton Central some lines are blocked.
'Train services running through this station may be cancelled, delayed or revised. Disruption is expected until the end of the day.'