Potable Water Supply
Water is essential for life, health, and economic development. Protecting water resources and ensuring access to safe drinking water is a shared responsibility.
WASCO is committed to providing reliable access to high-quality potable water while protecting the country’s water resources from pollution and environmental impacts.
Water Sources of Lesotho
Water continuously moves through the natural water cycle, including evaporation, condensation, precipitation, infiltration, groundwater movement, and surface runoff through rivers and storage dams.
WASCO obtains water from various sources, including rivers, dams, and reservoirs, which undergo treatment processes before being supplied to customers.
The main source of water for Maseru is the Metolong Dam, which supplies Maseru, TY, Roma, Mazenod, and Morija.
The Metolong Water Treatment Plant has an average production capacity of 75 megalitres per day (ML/day) and a maximum production capacity of 94 ML/day.
The plant uses modern water treatment technologies to produce high-quality drinking water. Advanced processes, including powdered activated carbon (PAC) dosing, potassium permanganate treatment, and activated carbon filtration, help control taste, odour, algae, and other contaminants.
Water Treatment
Water treatment ensures that raw water from natural sources is purified and made safe for human consumption. Through carefully controlled treatment processes, WASCO removes impurities, harmful microorganisms, and other contaminants to meet drinking water quality standards.
WASCO applies a multi-stage treatment process that includes:
- Pre-settlement
- Coagulation
- Flocculation
- Sedimentation
- Filtration
- Disinfection (Chlorination)
Water Treatment Process
1. Pre-settlement: Pre-settlement removes excess sediments and reduces water turbidity through natural settling. This initial stage improves the efficiency of subsequent treatment processes.
2. Coagulation: During coagulation, chemicals such as organic polymers are added to the water to bind small particles together and form larger particles known as flocs.
3. Flocculation: Flocculation gently mixes the water, allowing smaller particles to combine and form larger flocs that can be removed more easily.
4. Sedimentation: During sedimentation, the heavier flocs settle at the bottom of tanks, while clearer water flows onward for further treatment.
5. Filtration: The filtration process removes remaining fine particles and impurities, improving the clarity and quality of the treated water.
6. Chlorination: Chlorination is used to disinfect water by eliminating harmful bacteria and microorganisms. Chlorine levels are carefully controlled throughout the process to ensure water remains safe from the treatment plant to the customer’s tap.
Quality Assurance
WASCO applies a multiple-barrier approach to water treatment, combining coagulation, flocculation, sedimentation, filtration, and disinfection to ensure safe and reliable drinking water.
Continuous monitoring and testing are conducted throughout the treatment process to verify treatment effectiveness.
WASCO also regularly collects and analyses water samples from customer taps across its service areas. Water quality testing is conducted in accordance with international standards, including the World Health Organization (WHO) Guidelines for Drinking-water Quality.
Through rigorous quality control and monitoring, WASCO ensures that customers receive safe, clean, and reliable drinking water.
