This kind of thing - unfortunately - does happen. Likely more often than one realizes.

Here, back in Sept. 2002, the City of Winnipeg's sewage system had a drastic failure. Resultant of 462,500 cubic meters (122,179,596 US gal.) of raw - untreated sewage pumped into the Red River. During the fall-out of the failure, I found out this system fails on average - 11 times a year - not in same quantities - but repetative failures.

What happened to the City - nothing. Sure - court dates and charges - they got a slap on the wrist with a please fix-it. Recommendations for fixing - that's about it. (I'll stop before I rant).

There was a short upset to the rivers fishery on the big dump - but nothing severely noticeable to the average fisherman. There was more the impact to recreational activites (ie/ beach-going) due to high e-coli levels. Now this is warm water species (channel cats, carp, freshwater drum, sauger, walleye, northern pike, etc.). The fishery survived and is still going strong - maybe due to tolerance already attained by the repeat offences ? .. ? .. ? ....... Still - not something we like to hear about (or wade in) ......