I embarked in a river location, in which the river shared some squares with a murky pool. Apparently there's a bug in the current version of Dwarf Fortress, which means that the river is slowly becoming stagnant, spreading from the intersection tile.
How can I fix this? Is there another program that can be used to edit the location to move/delete the murky pool and remove the stagnant-flag from the affected river tiles?
It's slowly creeping closer to my well, so please hurry!