Public beaches were popular on the Charles River banks of Boston and Cambridge, MA. But in the mid-20thC swimming was banned due to pollution from industrial run-off upstream. Today, two generations later, the industry is long gone and the pollution content of the Charles River is finally low enough for safe public swimming. One huge problem is that while the water has been flushed of toxins, the sediment of the riverbed is overlain with concentrated toxic matter that precipitated out through the pollution years. Swimming cannot disturb this sediment or the water quality will plummet to hazardous levels. Eventually this area too will be flushed of toxins through natural processes, but that will probably only come to pass over several centuries.
The obvious solution is to dredge out the contaminated material, dispose of it in a landfill and replace it with clean material [creating a beach]. This solution is not only very expensive but fraught with the risk of even greater environmental harm. Why should the contamination merely be shifted to an undisclosed once-uncontaminated location? It would be best for it to remain in place to cleanse naturally.
Idea:
A wooden mesh platform [really big bamboo blind-esque] the size of a very large public pool is anchored to the 'beach' which could be a sand crib following the shore. The mesh platform is flush with the sand and can be rolled out where it floats low in the water but safely above the sediment bed. This will be the beach going out into the water for the bathers. A long bench could be at the deep end so bathers could sit out on the edge like a pool. In the winter it could roll back out of the water and up on the beach like a big frozen wave.-- scootie, Dec 26 2008 I'm just curious as to which contaminants we're talking about here.-- pertinax, Dec 26 2008 I would paddle my canoe up from Hartford to sit on the beaches of the River Charles. (If the water were cleaned up.)-- blissmiss, Dec 26 2008 FYI from: http://crwa.org/ watershed/sediments.html
“During the past century, sediment that accumulated in the Lower Basin has contained many inorganic elements (such as chromium, lead, copper, and mercury) as well as organic compounds (such as DDT and fossil-fuel combustion products like polyaromatic hydrocarbons). While some of the inorganic elements could have resulted from the natural breakdown of rocks, the presence of organic compounds can only be from human activities.”
I'm sure the caisson dam/dredging would work, but at great cost and with the 'disposal' of contaminated material, which means contaminating some other place. Part of the idea was that we must live with the waste since we created it.-- scootie, Dec 26 2008 //I don't think the problem is specific to one river//....? and?-- scootie, Dec 26 2008 So, have the authorities banned smoking within a 100 feet of the Charles river now?
el dueno-- el dueno, Dec 27 2008 [UnaBubba] Oh. No problem, use it everywhere you like...
It is not wishlisting. It is a cheaper alternative to caisson dam/dredging and a more fun/natural experience to just building a pool next to a river.-- scootie, Dec 27 2008 [el dueno] no smoking ban yet on the Boston side but you probably can't by cigarettes on the other side in the People's Republic of Cambridge.-- scootie, Dec 27 2008 random, halfbakery