Wells, springs and mine sites with parameter concentrations that have equaled or exceeded drinking water standard(s), including location and parameter(s) are shown in Table 5.3-7A.  Impaired lakes and streams with site type, name, length of impaired reach, area of impaired lake, designated use standard and parameter(s) exceeded is shown in Table 5.3-7B.  Figure 5.3-10 shows the location of water quality occurrences keyed to Table 5.3-7.  All community water systems are regulated under the Safe Drinking Water Act and treat water supplies to meet drinking water standards.  Not all parameters were measured at all sites; selective sampling for particular constituents is common. A description of water quality data sources and methods is found in Volume 1, Appendix A. 

Well, Mine or Spring sites that have equaled or exceeded drinking water standards (DWS)

• Refer to Table 5.3-7A.

• Nine sites have parameter concentrations that have equaled or exceeded drinking water standards.

• Standards equaled or exceeded in this basin include arsenic, nitrate, beryllium, radionuclides and organic compounds.

Lakes and Streams with impaired waters

• Refer to Table 5.3-7B.

• Water quality standards were equaled or exceeded in three stream reaches on two streams.

• The standard exceeded in all reaches was E. coli.  The two reaches on Tonto Creek also exceeded the standard for nitrogen.

• All three impaired reaches are part of the ADEQ water quality improvement effort called the Total Maximum Daily Load (TMDL) program.  The final TMDL reports for the streams have been completed and draft implementation plans are available for the two reaches on Tonto Creek.