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July 13, 2005
Chlorinated water and vegetation
I am managing a project for the Paxton Creek Watershed and Education Association that will entail retrofitting bioretention into a pair of stormwater detention ponds at a township-owned recreational facility. One of the ponds receives regular flows of highly chlorinated water (say 3 to 5 ppm chlorine) weekly when the whirlpool bath is emptied. The effect of this water seems to be evidenced by a "shoreline" below which no vegetation survives. The pond is planted in turf grass.
The other pond, which receives roof and parking lot runoff, has fairly healthy turf and a pretty nice stand of emergents in the low area, so the whirlpool discharge would seem to be the culprit.
Here's the question: can someone recommend vegetation that would stand up to the chlorine? We cannot ask the township to modify its practices, so we have to find a way to live with the discharge.
Posted by aquacura.com at July 13, 2005 09:46 AM
Comments
Jack Matson commented (attached to another category on the weblog) that, of course, chlorine is a biocide, intended to kill living things. He suggested that we either spray the water into the air to dissipate the chlorine or have the water pass through vegetative material (straw bales, for instance) to reduce the chlorine. Along those lines, how about a compost berm? The water passing through it would encounter a great deal of organic material, which would reduce the chlorine.
Any thoughts?
Posted by: Dave Sheridan at July 13, 2005 09:15 PM
Try Switchgrass. It is pretty resistant to Chlorine, and will also abosorb it. I think it will work at 5ppm, but you might want to check that.
Posted by: Cory Miller at July 19, 2005 11:06 AM
Do you know about this "Living Water Garden" project in China? http://www.keepersofthewaters.org/lwg.cfm
Thought you might be interested.
Posted by: Sally Mattison at August 9, 2006 06:03 PM
Thanks, Sally, for the link. I had not heard of this group, but have bookmarked their site. John Todd's Ocean Arks was working on a project in highly polluted canals in China. He was using his floating vegetation beds to clean some very nasty water, and was seeing some success. Technical and financial problems interfered. Here's a link: http://www.oceanarks.org/restorer/
Posted by: Dave Sheridan at August 11, 2006 11:52 AM