The following are a selection of data elements. Many of the elements listed below are not required to be reported and are therefore not available for all public water systems. Data, when available, may be analyzed at numerous spatial levels, including national, Regional, State, county, community, and ZIP code. Records have facility specific latitude and longitude values, including those generated from ZIP codes. In accordance with EPA policy, latitude and longitude will have to be reported for each PWS water intake point on a phased basis, beginning in 2000 and complete by 2004.
Dates are available for all violations and when systems return to compliance.
It is difficult to analyze trends in contaminants since only levels exceeding the MCL are reported. There is a standard reporting timeframe. Inventory is required annually, all other data is required quarterly. Any violations that are identified within the last quarter must be reported within 45 days of the end of the quarter within which they were identified. For instance, some rules specify the reporting of annual averages.