Discuss the role of state and local public health agencies in insuring high quality drinking water
Keeping the high quality of drinking water and maintaining safe disposal of public wastes are the basic tools to ensure the health of the community.
In 1974, Congress passed the Safe Drinking Water Act (SDWA) to protect public health and to establish national drinking water standards. The Environmental Protection Agency (EPA) established the Public Water System Supervision (PWSS) program under the SDWA’s stipulations. The EPA sets the rules to ensure safe water for human consumption, including Maximum Contaminant Levels (MCLs), treatment techniques for contaminant drinking water, monitoring, reporting, and notifying violations to the public.
Continuously since 1912, Virginia has had its own protective state public drinking water program within the VDH, maintaining primacy for the PWSS program since 1977. Virginia submits data to the EPA’s Safe Drinking Water Information System (SDWIS) on a quarterly basis including inventory statistics, incidence of MCLs, violations and enforcement actions. Virginia also reports to the EPA on annual basis about MCLs, treatment techniques, variance and exemptions, and violations.
Public Water Systems (PWS5) are defined as systems which use potable water lines under pressure to connect to at least 15 service connections or serve 25 people for 60 days each year at a minimum. The PWSs serve communities (towns, homes), non-transient communities (schools, factories) , and transitional non-communities (restaurants, parks). PWSs are operated under permit through the Waterworks Regulation to ensure properly standardized drinking water treatment and distribution’).
In Virginia, the average personal water consumption is 100 gallons per person per day, making sewage and wastewater treatment very important. The state’s program for sewage and wastewater regulation is mandated by the state’s Health Laws. Currently, all centralized municipal and private sewage collection, treatment and sludge management operations are overseen by either the Virginia Discharge Pollutant Elimination System (VPDES) or a Virginia Pollution Abatement (VPA) permit. The Department of Environmental Quality administers the regulations to manage these programs.
A water and wastewater treatment process consists of a progressive combination of unit operations. Mandated by state law, the conventional treatment for the purification of surface water for drinking water includes flocculation coagulation, sedimentation, filtration, and disinfection. Wastewater treatment includes several levels; primary (removing portions of suspended solids), secondary (biological treatment altering solids content), and tertiary (reducing/removing difficult contaminants) treatment. Tertiary treatment may also use Advanced Water Treatment including chemical clarification and filtration’)
The septic tank is a natural sewage treatment and disposal system, which relies on bacteria to digest and clean wastewater. Mostly used by private homeowners, these can sometimes cause contamination due to a lack of knowledge and/or poor maintenance. Both federal and state agencies have specific regulations covering septic tanks, which have precise numerical standards and requirements to limit the danger’)
The contamination strength of wastewater is represented by the concentration of physical, biological, and chemical contaminants or pollutants. In measurement, Biochemical Oxygen Demand (BOD) represents the original organic matter content of wastewater being processed. After digestion, solids and many other contaminants are tested for after treatment and the wastewater may be further processed to a standard level of purity.
Microbial disinfection of wastewater is used to minimize the numbers of microorganisms reintroduced to the environment’). Some pathogenic organisms present in treated un-disinfected sewage effluent can cause infectious diseases. Under law, sewage effluents should be disinfected and adequately diluted when being discharged. Chlorination is a conventional disinfection method for both drinking water and wastewater. Its performance reliability is well established.
Ultraviolet light irradiation systems and ozonation system are among the other more expensive options available.’)
The potable water which human beings use comes primarily from rain, surface sources (rivers, lakes), and ground supplies (percolation of rainwater and runoff. Treated wastewaters can also be a water resource, reused for irrigation, industrial, some recreational, and non-potable residential purposes. In Northern Virginia, operated by the Upper Occoquan Sanitary Authority, treated wastewater is used as a potable water supply due to supply shortages. Recycled drinking water treatment requires an additional level of safeguards and an advanced wastewater treatment facility’)
Keeping and protecting our water resources are extremely important to the public health, needing not only government regulations but also every resident’s effort.