The accident here was, not only did the technician use Galveston tap water, but by this time, the city of Galveston, which had a rather corrupt government at that time, it was well known throughout the United States. The water supply for Galveston, which is a city on an island right off shore from the mainland of Texas, its water supply is supplied through a large pipe running under Galveston Bay from the mainland to the island, and that's a rather large diameter pipe, and that's the source of Galveston water.
Over the years corrosion occurred in this pipe, allowing Galveston... sea water to enter and mix with the fresh water. It so happened that the city leaders were persuaded not to make repairs in this pipe because it would have been a situation that would have annihilated all of the sellers of fresh water to residents of Galveston, so they paid off the city leaders not to repair the pipe. Well, that was a huge plus for science, because the osmolarity of the water that the technician had mistakenly used was hypotonic, which means that it allowed the cells to swell, and that's what provided the conditions for spreading the chromosomes. To this day people who use that technique, and there are thousands, when they make up the solution to provide the spreading phenomena, proper osmolarity, are essentially making Galveston tap water of the 1950s.