I have been watching magnet fishing and people love to toss stuff over bridges without a second thought on the environmental impact. Hiding evidence I can almost understand but not lawnmowers, car batteries, etc.
It seems deeper fines should be made to discourage this terrible behavior.
I doubt that anyone has researched the origin of such junk in detail.
If it doesn’t fit in your rubbish bin, generally it costs time, effort and money to properly dispose of things. Tossing it off a bridge is efficient.
Likely there’s a not inconsiderable proportion of anti-social behaviour, like stealing a bike and throwing it into a waterway afterwards.
Mostly the second point. I would wager from experience that the majority of small man-portable conveyances that wind up at the bottom of lakes and rivers are there because they were stolen and thrown there. Bikes, motorcycles, rental scooters, shopping carts, etc. The reason is hooliganism, and the contributing factors are alcohol and teenagerhood.
Just for the record, teenage hooligans-in my experience -are actually preferable to the adult hooligans.
Seriously. Teenagers might get drunk and do stupid shit but they’re scared of getting caught and run away. Many times they’ll even clean up after themselves if you’re not a total dick.
Adults tend to stand their ground and pick fights.
(Also, every demographic you care to name steal shit. Sobriety, income, race. None of it matters.)