Part of an hydroelectric complex counting four dams, Manic 5 and Manis 5 PA are two power houses installed in the valley of the Manicouagan river, north of Québec. Unveiled in 1970, this plant represents the higher multiple-arch and buttress dam in the world.

For the Manic 5 and Manic 5 PA sanitary water treatment, Hydro-Québec mandated the Groupe-conseil TDA to find a compact system that could be contained into a “treatment room” and allow a gravitational flow. The BIO-FOSSETM was in fact the right technology meeting all these specific criteria.

Following the evaluation of several technologies available on the market, Hydro-Québec opted for the H2O Innovation’s system of biofiltration: the BIO-FOSSETM. The company system had been chosen for its highperformance, its ease of maintenance and its small footprint.

The BIO-FOSSETM is a biological fixed growth process treating wastewater which is used after a primary treatment, usually a septic tank. The BIO-FOSSETM includes fine bubble diffusors and a synthetic textile which offers the ideal conditions for the wastewater treatment by micro-organisms.

Treatment Line

The treatment system is equipped with a septic tank (primary settling) which holds a part of the solids coming from the sanitary plants. The water that flows out of the septic tank is sent to the regulation tank which pre-oxygenates the water before it discharges in the principal section of the treatment: the BIO-FOSSETM. Then the suspended solids are hold in the secondary settling tank which clarifies the water before it drains away. For both Manic 5 and Manic 5 PA BIO-FOSSETM systems, the water that flows out the settling tank are discharged directly in the Manicouagan river. A sludge tank is also installed to store the biological sludge which is taken out from the settling tank. Finally, the system is set up under negative pressure in order to collect the odours that could emanate from the aerated biological system.

Results

• The Manic 5 and Manic 5 PA BIO-FOSSETM systems treat respectively 3 m3 of water per day
• The treated water is discharged directly in the Manicouagan river
• The systems do not require much maintenance (only 5 to 10 minutes per week)
• The water discharged is safe and respects most stringent standards (BOD5 = 4 mg/l , TSS = 13 mg/l)
• The systems do not emit any odour even if they are installed inside the power houses
• Hydro-Québec is very satisfied with the results obtained and is impressed by the ease of operation.

For Free Access to the full case study in PDF format click here