03/23/2015 11:51 EDT | Updated 05/23/2015 05:59 EDT

Montreal upgrading wastewater treatment with ozone filtration

The City of Montreal will install an ozone filtration system at its Jean-R. Marcotte​ wastewater treatment plant in Rivière-des-Prairies.

This project will be the the world's largest waste water treatment plant to use ozone filtration..

The city says ozone filtration does a better job of reducing the risk of water-borne viruses and bacteria and cleansing traces of cosmetic and pharmaceutical products and industrial waste.

For example, the city says ozone filters are 99 per cent effective at removing fecal coliform and enterococcus bacteria.

The city already uses ozone filters to treat its drinking water.

Ozone filters also do not require chemical additives to be mixed with water.

The plant treats wastewater before it is returned to the St. Lawrence River to reduce contamination.

It treats 2.5 million cubic metres of water daily, the equivalent of the volume of the Olympic Stadium.

Right now the city uses chemical additives to treat water.

The city says it has already completed feasibility studies and it will issue a call for tenders to install the ozone filters next month.

The system is expected to be running by 2018.

The city estimates the total cost for the project to be $98.5 million for installation, and $9 million annually in operating costs.

The provincial and federal governments will cover 85 per cent of the cost as part of a joint infrastructure program.

Ozone filters work by passing water through high-intensity ultraviolet lamps. 

The ozone acts as an oxidant which eradicates harmful bacteria and additives with no byproducts.