Treatment Plants

The Authority manages the following 10 Wastewater Treatment Plants:

Item NoWastewater Treatment PlantDesign Flow (m3/day)Average Actual Flow (m3/day)Level of TreatmentTypes of effluent received for treatment (Industrial/Domestic/Leachate/etc)Use of treated effluent (irrigation, borehole injection/sea outfall, etc)
1

Montagne Jacquot

48,00033,000 - 38,000Advanced PrimaryIndustrial/DomesticSea Outfall
2

St Martin

69,00055,000 - 59,000TertiaryIndustrial/DomesticIrrigation/Sea Outfall
3

Grand Baie

5,5002,000 – 2,500TertiaryDomestic
Irrigation/Borehole Injection
4

Baie Du Tombeau

48,00033,000 – 38,000Preliminary Treatment
(Wastewater Plant)
Industrial/DomesticSea Outfall
5

Pailles

270Secondary followed by Chlorination
DomesticLeaching Field
6

Bois Marchand

550Secondary followed by ChlorinationDomesticLeaching Field
7

R. Du Rempart

270Secondary followed by Chlorination
DomesticLeaching Field
8

Flacq

400Secondary followed by Chlorination
DomesticLeaching Field
9

Dubreuil

270Secondary followed by Chlorination
DomesticLeaching Field
10

Vuillemin

400Secondary followed by Chlorination
DomesticLeaching Field

Major Wastewater Treatment Plants

Constructed in 2007, the Mt. Jacquot Wastewater Treatment Plant has a hydraulic design capacity of 48,000 m3/day, and provides an advanced primary treatment process, whereby the influent undergoes coagulation and flocculation process followed by primary sedimentation. It receives both domestic and industrial wastewater via two (2) main pumping stations, namely, Fort Victoria and Pointe aux Sables. Primary Sludge extracted from the primary sedimentation tanks are thickened and dewatered in a belt filter press and stabilized with hydrated lime prior to carting away to the Mare Chicose Landfill.

The St Martin Wastewater Treatment Plant was constructed in 2004, and has a hydraulic design capacity of 69,000 m3/day and treats wastewater up to tertiary level. The wastewater is treated in three (3) stages in the plant comprising inter alia of the primary, secondary and tertiary treatment process. The tertiary treated effluent from the plant is either supplied for the irrigation of sugar cane through 2 Nos. irrigation canals, namely, La Ferme and Magenta or discharged to the sea outfall. The more so, it is used for landscaping irrigation, as service water for cleaning on the plant, and a source of water for jetting units.

The sludge generated from the primary settling tank and secondary treatment are thickened and undergo stabilization through anaerobic digestion and finally dewatered prior to carting away to the Mare Chicose Landfill.

The Plant also includes a Combined Heat & Power system for the heating of sludge for digestion and power generation. The electricity generation through co-generation is about 20 to 25% of the total plant energy consumption

The Grand Baie Wastewater Treatment Plant was built in 2003. It has a hydraulic design capacity of 5,500 m3/day, and receives its wastewater from a network of 19 pumping stations located in different parts of Grand Baie. The wastewater is purely from domestic sources and undergoes treatment in three (3) stages at the plant which comprise inter alia of the primary (aerated chamber to remove grease and grit), secondary (Activated Sludge Plant for nutrients removal) and tertiary treatment process (Disc Filters and Chlorination). The tertiary treated effluent from the plant is injected in three (3) boreholes located nearby to the plant and in near future will be used for irrigation of golf course. The sludge generated from the secondary treatment are dewatered and stabilized with hydrated lime prior to carting away to the Mare Chicose Landfill.

The Baie du tombeau Wastewater Treatment Plant was built in 2000, and has a hydraulic design capacity of 48,000 m3/day and provides a preliminary treatment whereby the influent undergoes grit removal and screening. It receives wastewater from two main pumping stations namely Baie Du Tombeau no. 1 and Roche Bois.

The WMA has 6 small Wastewater Treatment Plants which receive only domestic wastewater. Currently situated at Pailles, Bois Marchand, Riviere du Rempart, Flacq, Dubreuil and Vuillemin, they were constructed in the years 1995 to provide secondary treatment of wastewater.

Small Wastewater Treatment Plants

Location Treatment Capacity
Pailles270m3
Bois Marchand550 m3
Riviere du Rempart270 m3
Flacq400 m3
Dubreuil270 m3
Vuillemin400m3