Water Quality

Drinking water quality

• More on Water Quality Guidelines
• More on: CWA Water Quality
• More on:  WRU Water Quality

Drinking water quality in Mauritius is generally of a high standard, thanks to the country's commitment to providing safe and clean drinking water to its population. The government of Mauritius has implemented rigorous water quality standards and monitoring systems to ensure that the water supplied to its citizens meets international health and safety guidelines. The water treatment infrastructure, which includes processes such as filtration, chlorination, and disinfection, plays a crucial role in maintaining water quality.

Mauritius has taken measures to protect its water sources, including the management of watersheds and controlling pollution to prevent contamination. Additionally, regular water quality testing and monitoring are conducted to identify and address any potential issues promptly. This dedication to clean drinking water has not only benefited the health and well-being of the population but also supports the country's thriving tourism industry.

Surface water quality

Surface water quality in Mauritius varies depending on the specific bodies of water and their proximity to human activities.

The island nation has a diverse range of surface water sources, including rivers, streams, lakes, and lagoons.  

• Lagoons and Coastal Waters: The lagoons, which are subject to various environmental pressures due to urbanization, agriculture, and industrial activities. Pollution from urban and agricultural runoff can affect the water quality of these lagoons. However, the Government of Mauritius has taken steps to manage and protect these critical ecosystems through legislation and monitoring.
• Rivers and Streams: The water quality of rivers and streams can vary depending on their location and the surrounding land use. In areas where agricultural runoff and industrial discharges occur, surface water quality may be impacted. Proper land management practices, including erosion control and reducing pollution, are essential to maintain the quality of these water bodies.
• Freshwater Lakes: The freshwater lakes are valuable resources for both the environment and the local communities. Pollution and sedimentation can affect the water quality of these lakes, but efforts are made to manage and preserve these natural assets.
• Water Quality Monitoring: Mauritius has established water quality monitoring programmes to assess and address the quality of its surface waters. Regular testing and surveillance help identify areas where water quality may be compromised, allowing for timely corrective actions.
• Conservation Efforts: The Government of Mauritius, along with various environmental organizations, is committed to protecting and conserving surface water bodies. Conservation efforts include watershed management, reducing pollution, and enforcing environmental regulations to safeguard water quality.

It's worth noting that while many efforts are in place to protect surface water quality in Mauritius, challenges such as population growth, urbanization, and agricultural expansion continue to put pressure on these valuable resources. Sustainable land management practices and ongoing monitoring and conservation efforts are essential to maintain the quality of surface waters in the country.

Groundwater quality

Groundwater quality in Mauritius is a critical aspect of the country's water resources, as it plays a significant role in supplying both drinking water and supporting agriculture. Several factors impact groundwater quality in Mauritius:

• Salinity: The island's volcanic origin has led to the presence of various types of groundwater. In some areas, especially along the coast, groundwater may be influenced by saltwater intrusion, affecting its quality. This is a common challenge for islands with limited freshwater resources.
• Agricultural Practices: Pesticides, fertilizers, and other agricultural chemicals can potentially seep into the groundwater, impacting its quality. Proper management practices are essential to minimize contamination risks.
• Urbanization: In urban areas, industrial activities, sewage, and runoff can introduce pollutants into the groundwater. Wastewater treatment and storm-water management are crucial to prevent groundwater contamination.
• Wastewater Disposal: Improper wastewater disposal, especially from septic tanks and soakaways, can pose risks to groundwater quality. Ensuring proper sanitation and sewage systems is vital.
• Natural Occurrence of Contaminants: Some areas may naturally have higher concentrations of certain contaminants in the groundwater. Monitoring and treatment are necessary to provide safe drinking water.

Mauritius has made significant efforts to manage and protect its groundwater resources. The government conducts regular water quality monitoring and has established standards to ensure that the water supplied for drinking is safe. Additionally, community education and awareness programs are in place to encourage responsible groundwater use.

To maintain and improve groundwater quality, continued vigilance, sustainable land and water management practices, and investments in wastewater treatment and pollution control are essential. The protection of groundwater quality is vital not only for human health but also for the sustainability of agriculture and ecosystems on the island.

 Inland Waters Statistics  

Freshwater quality from selected boreholes by selected parameters

(Source: Digest of Environment, Table 29, 2023)

River water quality by selected physico-chemical parameters

(Source: Digest of Environment, Table 30, 2023)

Coastal and Marine Water Quality

Tourism and Recreational Activities: The country's picturesque coastal areas and beaches attract a significant number of tourists. While tourism contributes to the economy, it also places pressure on coastal waters due to increased human activities and potential pollution.

Fishing and Aquaculture: Coastal and marine waters are essential for the livelihoods of local fishermen and the aquaculture industry. Maintaining water quality is crucial to safeguard fish stocks and the seafood industry.

Shipping and Port Activities: Mauritius has a bustling port, and shipping activities can introduce pollutants and potential hazards to marine waters. Proper regulations and monitoring are necessary to mitigate environmental risks.

Coral Reefs and Biodiversity: The health of coral reefs and marine ecosystems is closely tied to water quality. Pollution and climate change-induced factors can adversely affect coral reefs and the diverse marine life they support.

Climate Change and Sea Level Rise: Rising sea temperatures and sea levels, attributed to climate change, can impact coastal and marine water quality. It can lead to coral bleaching events and the intrusion of saltwater into freshwater bodies.

Marine Pollution: Pollution from various sources, including industrial discharges, urban runoff, and shipping, can introduce contaminants into coastal and marine waters. Oil spills, in particular, can have devastating consequences for marine ecosystems.

Cyanobacterial Blooms: Occasional cyanobacterial blooms in coastal waters can pose health risks to both humans and marine life. Nutrient runoff from agriculture and other sources can contribute to these blooms.

To address these challenges, Mauritius has implemented measures to protect coastal and marine water quality. These include stringent regulations, regular monitoring, and the enforcement of environmental standards. The government also promotes sustainable fishing practices and conservation efforts to protect coral reefs and marine biodiversity. Despite these efforts, ongoing vigilance and proactive measures are required to address the complex interplay of factors impacting coastal and marine water quality. The preservation of these vital ecosystems is essential for both environmental sustainability and the economic well-being of the country.

Coral spawning - November 2023 episode (courtesy: S Jawaheer)

Turtle close to mangroves (courtesy: S Jawaheer)

Coastal/Marine Waters Statistics  

Range of levels of Nitrate-Nitrogen, Phosphate, and Chemical Oxygen Demand (COD) at established coastal sites 

(Source: Digest of Environment, Table 31, 2023)

Total Coliforms (TC) and Faecal Coliforms (FC) in coastal water at monitoring site and by station (2023)

(Source: Digest of Environment, Table 32, 2023)

Physical and chemical characteristics of coastal water by level and monitoring site - since 2017

(Source: Digest of Environment, Table 33, 2023)

Sea water quality in the lagoon at Terre Rouge Rivulet Bird Sanctuary, 2010 - 2019

(Source: Digest of Environment, Table 34, 2023)