Site: C1 (Inlet) and C2 (Outlet)

C1 is where water partially treated by the phytoremediation system, enters.

The water is further being treated by water plants like the Water Canna, Common Rush, Lotus and Papyrus Sedge as it flows through the C-shaped pond before exiting out of C2. These water plants take up chemicals that become pollutants if not removed, and metabolises them. Examples are phosphates and nitrates that are needed in a plants diet for healthy growth.

Certain plants, like the Water Canna, carry out phytotransformation and help transform recalcitrant compounds found in organic pollutants, such as pesticides and solvents, into non-toxic compounds that are not harmful to the environment. They do this by partially breaking down these compounds (in metabolism) as such compounds cannot be broken down to their most basic molecules by water plants. Most of the plants, like the Common Rush, simply take up nutrients and filters suspended solids in the water at the same time.

The distance of C1 and C2 combined is long and filled with considerably large amount hydroponics. Hence, it is ensured that almost all of the unwanted nutrients in the water are taken up by the hydroponics before it enters the pond. This is proven by the decrease in Total Dissolved Solids and Chloride concentrations, Turbidity, Hardness, BOD and COD values from C1 to C2 (Table A).

Table A