This beautifully deceiving “lagoon” is actually a toxic soup filled with cars, carcasses, and trash…of course this doesn’t stop people going for a dip. So the town dyed it black!
Former quarries often flood, forming swimming holes perfect for dangerous leaps off of cliffs, and horsing around with friends. Unfortunately they can also have some nasty residues left over from their industrial days.
In the case of the blue lagoon, calcium oxide, used as part of the quarrying process has left the lagoon with a pH of 11.3, compared to ammonia’s pH of 11.5 and bleach’s pH of 12.6. If that is not enough, the site has been used as a dumping ground. Signs leading up to the lagoon read:
“Warning! Polluted water. Lagoon known to contain: Car Wrecks, Dead Animals, Excrement, Rubbish” and “Warning! Do not enter water, due to high pH levels. This can cause: Skin and eye irritations, Stomach Problems, Fungal infections such as thrush” and “Think! would you swim in ammonia or bleach?”
However the draw of the turquoise water, turned green as limestone rocks leach calcite crystals into the water, is simply too alluring. Families drive to the lagoon and children regularly go swimming in it with the simple warning not to dunk their heads or swallow any water.
Update: As of early 2018 the lagoon is now black and been told by police it will continue to be like this for the foreseeable future so swimming not advised as it could dye your skin.