Water Treatment
To ensure that the water is safe for drinking, the NWC subjects the water to an expensive treatment process, which involves:
- The collection of the untreated water from surface water sources (rivers or streams), or from underground sources (wells or springs) via intake works.
- The water is then taken through pipes to a treatment plant, which is specially constructed and equipped for this purpose.
- At the treatment plant, expensive equipment and chemicals are then utilised to treat the water that is later distributed to customers.
Although the specific details may vary depending on the type of treatment system available, the water treatment process usually involves five (5) distinct stages. They are:-
- Screening and Aeration
- Coagulation and Flocculation
- Sedimentation and Disinfection
- Filtration
The process described above may be shortened or compressed depending on the quality of the raw water source, the available treatment infrastructure, the preferred treatment method or other factors. For instance, water that is taken from the aquifer via wells is usually only disinfected. This is so because this water is usually much purer than surface water because it is filtered naturally through the earth before rising to the surface.
All through the water treatment process the water is tested to make sure that the quality is just right. Some of the water samples that are collected are taken to a laboratory where they are examined to make sure that the water meets the Interim Jamaica Drinking Water Criteria and the World Health Organization (WHO) standards.
Water quality is monitored to quantify the following:
| Nitrates | Calcium | Total coliform | Nitrites | Sodium |
|---|---|---|---|---|
| Total Faecal Coliform | Silica | Magnesium | Total solids | Total Dissolved Solids |
| Iron | Manganese | Total Suspended Solids | Phosphates | Sulphate |
| Fluoride | Chloride | Total Plate Count | Specific Conductivity | Aluminium |
| Alkalinity | Turbidity | Colour | Chemical Oxygen Demand | Biochemical Oxygen Demand |
Health and aesthetics are the main determinants for the safety of water. The NWC uses the Interim Jamaican Criteria developed from WHO guidelines to set the standards for the potability of water. The NWC also conducts research and implements cost-effective solutions for the treatment of Jamaica's water supplies.
Our team consists of a range of chemists, microbiologists, environmental scientists as well as trained laboratory analysts, laboratory attendants, field assistants and administrative staff committed to providing accurate data to ensure the best potable water quality - free from coliform bacteria, free from colour, odour and taste.
Also see : Wastewater Treatment