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Resources and references
About the Great Lakes LaMPs study...
Glossary of terms
In Ontario, drinking water quality is addressed by the Ontario Drinking Water Objectives. There is no organized water quality monitoring program for private water supplies. However, the public water treatment plants are required to regularly monitor the finished water for chemical and microbiological quality as outlined in the Ontario Drinking Water Objectives.
The Ontario Ministry of Environment’s Drinking Water Surveillance Program (DWSP) monitors raw (incoming source water), treated (at the treatment plant after water has been treated), and distributed water (at the consumer’s tap) at selected locations throughout the province for over 200 parameters. DWSP maintains a database of contaminant levels measured in raw, treated and distributed water from about one quarter of all municipal treatment plants in Ontario, representing about 85% of the population serviced by municipal water supplies..
The U.S. EPA has established legally enforceable standards for public water systems called National Primary Drinking Water Regulations (NPDWR). These standards are used to protect the quality of drinking water by limiting levels of contaminants in public water systems that can adversely affect public health. Public water systems are required to monitor drinking water for a host of contaminants to ensure consumer safety. Frequency of monitoring in the U.S. is dependent on the type of system, whether the source water is surface or groundwater, the type of contaminant, whether or not a contaminant has been previously detected or has exceeded the standard, and the number of people served by the public water system.
Currently, the U.S. EPA does not regulate aluminum under its drinking water program but has a secondary, non-enforceable standard of 50-200 µg/l (this number is based on organoleptic properties). The U.S. EPA is working to determine if aluminum is of health concern and has placed aluminum on its Contaminant Candidates List (CCL). This list is the source of priority contaminants for the Agency’s drinking water program. Priorities for drinking water research, occurrence monitoring, guidance development, including the development of health advisories are drawn from the CCL. The CCL also serves as the list of contaminants from which the Agency will decide whether of not to regulate specific contaminants.
The U.S. EPA requires public water systems to be monitored for bacteriological, inorganic, organic, and radiological contaminants. Monitoring of drinking water includes physical and chemical characteristics of the water, as well as analysis for contaminants resulting from natural sources or human activities.
Information on local water quality is available from several sources, including the state public health department and local water supplier. To inform the public of the results of the chemical analyses of drinking water and to demonstrate a commitment to protect human health, the U.S. EPA requires each community water system to generate an annual Consumer Confidence Report (CCR) that is made available to all residents receiving water from that water system. CCRs provide information about the source of water used, its susceptibility to contaminants where a source water assessment has been completed, the levels of contaminants detected in the water, the likely source(s) of contaminants, and potential health effects of any contaminant detected above that specific Maximum Contaminant Level (MCL). Copies of CCRs exist at the state and county level, and can be reviewed to give an indication of overall quality of treated surface water and groundwater, and the condition of the drinking water service.
Each state also has a department that regulates drinking water systems, and these agencies can also provide information about the local water supply and its quality. In addition, the U.S. EPA maintains a database which contains information on individual ownership, locations, violations, and enforcement actions. Most state drinking water databases include system detection information.
Last modified: April 29, 2003