The Sainte-Angelique water treatment plant was commissioned in 1994 in order to reduce the iron and manganese contained naturally in the groundwater. WSP’s services were required to upgrade and increase the capacity of the plant from 10.5 MLD to 19 MLD. WSP performed preliminary studies, treatability pilot testing, detailed design, and contract administration for the upgrade and expansion.
The pilot testing included the physical/chemical removal treatment process, as well as the biological removal process of iron and manganese from underground water. Based on the outcome of the pilot testing, a chemical-free treatment was selected to be the preferred treatment approach. The transformation of the existing oxidation/greensand filters into biological filters allowed water production capacity to almost double, reaching 19 MLD, without enlarging the building. Other important benefits brought by the new technology were the significant savings on filtered water used for the backwash of the filters, and the interruption of potassium permanganate usage -- a hazardous chemical.
The drawings and specifications were prepared in compliance with the requirements of the new drinking water treatment design guidelines. Value engineering was performed in order to meet the client’s budget, which included the participation of the pre-selected biological filtration equipment supplier. One of the biggest challenges was maintaining the drinking water production at all times during this work, especially during the transformation of existing filters.