The current study is on East Calcutta Wetland (ECW) which is a model for multi-use resource recovery system with activities like pisciculture and agriculture. The entire city's soluble waste is disposed into the raw sewage canals which finally drains into the shallow, flat bottom fish ponds called Bheri. These sewage fed fisheries act simultaneously for the purification process like removal of heavy metals, coliform reduction as well as fish production at a commercial scale.