Treatment removes contaminants before water flows into homes
Municipal water, also known as tap water, undergoes treatment at a municipal plant to eliminate pathogens and other contaminants. It is then distributed to homes and industry through a network of underground pipes. Although municipal water is not treated to the same extent as filtered or purified water, it must meet the safety limits established by the United States Environmental Protection Agency’s (EPA) drinking water standards.
Municipal water, meeting the stringent EPA drinking water standards, is deemed safe for human consumption. It serves multiple purposes, including bathing, cooking, cleaning, and irrigating crops and landscaping. Moreover, municipal water is widely utilized by various industries for their operational needs.
Regular monitoring of municipal water quality is crucial, and appropriate actions must be taken if any contaminants are detected. This proactive approach ensures that the safety and integrity of the municipal water supply are maintained, and any necessary measures are implemented to address and mitigate the presence of contaminants.
Municipal Water Treatment Infrastructure
A municipal water supply can be sourced from rivers, lakes, reservoirs, or wells. This source water is extracted and pumped to a water treatment plant, where it undergoes a series of processes to remove impurities and ensure its quality. The treated water is then stored in tanks or reservoirs before being distributed to households and businesses through an extensive network of water pipes. This infrastructure ensures that consumers can access a safe and dependable supply of water flowing directly from their taps.
However, it is important to note that the quality of municipal water can vary due to differences in source water and treatment technologies employed in different regions. These variations can result in differences in the quality and characteristics of the supplied municipal water.
Contaminants Regulated by the EPA
The EPA oversees the regulations of 90 primary contaminants commonly found in drinking water, including pathogenic microbes, toxic chemicals, heavy metals, and more. The legal limits for each contaminant are set at levels that prioritize the protection of human health while also considering the capabilities of drinking water treatment plants utilizing the best available practices and technologies. Under the Safe Drinking Water Act, states have the authority to establish and enforce their own drinking water standards as long as they meet the minimum requirements set by the EPA.
How Municipal Water Is Treated
Various technologies and processes are employed for the treatment of municipal water, with the selection depending on the quality of the source water and the specific contaminants that need to be eliminated. However, irrespective of the water source, the ultimate objective of any water treatment process is to ensure that the water quality meets the EPA standard for drinking water. This ensures that the treated water is safe and meets the required standards for consumption.
The water treatment process consists of several essential steps. Coagulants, which are positively charged chemicals, are added to the water. These coagulants neutralize the negatively charged particles present in the water, enabling them to bind together with the chemicals and form larger particles through the process of coagulation.
Next in the water treatment process is flocculation, which involves gentle mixing to encourage the coagulated particles to form larger and heavier aggregates called flocs. Following flocculation, the water goes through sedimentation and clarification, during which the flocs, being denser than water, settle to the bottom of the sedimentation chamber. This process helps in clarifying the water and removing suspended particles.
The clarified water is subsequently subjected to filtration to eliminate contaminants and then undergoes disinfection to eradicate any residual pathogenic microbes. The specific technologies employed in the filtration and disinfection processes may vary based on the specific contaminants being targeted and desired treatment outcomes.
Filtering the Clarified Water
In the filtration stage, the clarified water passes through filters composed of materials like activated charcoal, gravel, and sand, which possess pores of varying sizes. These pores permit the water to pass through while capturing particles larger than the pore sizes. Filtration is highly effective in removing chemicals, dust, bacteria, viruses, and parasites. Additionally, activated carbon filters are effective in addressing unpleasant tastes and odors in the water.
AUC Group’s portfolio of technologies encompasses advanced solutions such as multimedia filtration, microfiltration, and ultrafiltration. Multimedia filtration employs a diverse combination of media to effectively target a broad spectrum of contaminants. In microfiltration, water is directed through filters with pore sizes ranging from 0.1 to 1.0 microns, without the need for excessive pressure. Ultrafiltration involves water passing through a membrane filter with extremely small pores, typically ranging from 5 and 100 nanometers. This ultrafiltration membrane allows water, salts, and other small molecules to permeate while effectively retaining larger particles and contaminants.
AUC also provides reverse osmosis, an advanced filtration method that effectively removes additional particles from water, including salts and other small molecules. Reverse osmosis is particularly useful for desalinating seawater or brackish water to make it suitable for drinking purposes or treating recycled water for reuse. Typically, reverse osmosis is employed following the pre-treatment steps of microfiltration or ultrafiltration, enhancing the overall efficiency and performance of the water treatment process.
After Filtration Comes Disinfection
Although filtration effectively removes impurities and enhances water clarity, it is important to note that certain pathogenic microbes may still be present. To eliminate bacteria and viruses, disinfection of the water is necessary. This can be achieved through various methods, including ultraviolet (UV) light, ozone, or chemicals such as chlorine or chloramine. Each of these disinfection methods serves the purpose of neutralizing any remaining pathogens, ensuring the water is safe for consumption.
However, it should be noted that UV light and ozone aren’t effective methods for microbes as the water travels through pipes to the point of use. As a result, chemical disinfection methods are more commonly employed to ensure that water remains safe and free from contaminants upon reaching the tap. Chemical disinfection methods provide a continuous and reliable means of maintaining water safety throughout the distribution system.
AUC specializes in a diverse range of technologies designed for treatment of well water and surface water sources. Our expertise extends to decentralized water treatment plants, enabling us to deliver clean drinking water to rural communities that may not have access to nearby municipal water treatment facilities. We encourage you to contact AUC to explore our comprehensive water treatment solutions and learn how we can assist in providing safe and reliable water to your community.