Yes and NO It depends what's ...
Published by Dahn Rosenquist, Laqua Treatment AB
Yes and NO
It depends what's in the water . Using wetland ( reed) you have no barrier if it would be any organic toxins in the water.
If it's "only" N in the water wetland is ok.
Better is to use bio-filter etc. Willow or other non food crop to uptake of NPK and the soil absorbs heavy metals. Willow will later then uptake the metals in the stem witch in combusting will be concentrated in the fly ash.
In Sweden many of the landfills use bio filtration in willow.
One other way is to put in a barrier etc peat ash, or activated coal
/dahn/
laqua.se