This could be a result of your design. Water always flows towards the nearest drop/hole as long as it is less than 7 blocks away. Your water is flowing out towards the channels you dug. For more info, read this: http://www.minecraftwiki.net/wiki/Water#Spreading
Happens to me too. Windows 7, Java 7
This could be a result of your design. Water always flows towards the nearest drop/hole as long as it is less than 7 blocks away. Your water is flowing out towards the channels you dug. For more info, read this: http://www.minecraftwiki.net/wiki/Water#Spreading