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For 1999 and after, click on the date for the corresponding eight-hour average peak ozone map for that day.

In October 2015, EPA revised the 8-hour ozone standard and changed the Air Quality Index (AQI) to align with this new standard. Maps for days in 2007 and earlier are based on the 1997 8-hour ozone standard (0.08 ppm). Maps for 2008 through 2015 are based on the 2008 ozone standard (0.075 ppm). Maps for 2016 through 2022 are based on the 2015 ozone standard (0.070 ppm). Click Here for a table showing the revised AQI breakpoints for the 1997, 2008, and 2015 ozone standards.

Bridgeport | Cornwall | Danbury | Greenwich | Groton | E. Hartford | Hamden | Madison | Middletown | New Haven | Stafford | Stratford | Torrington | Westport

Bridgeport
Operating from 1988 to 1997
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1994 6 11 0.117 June 18 0.093 July 2 0.092 July 13 0.082 July 6
1995 9 12 0.103 June 18 0.102 Aug 1 0.101 Aug 2 0.087 Aug 21
1996 4 5 0.082 July 6 0.081 July 18 0.080 Aug 4 0.079 Aug 23
1997 10 16 0.101 July 15 0.097 June 29 0.095 June 21 0.089 July 14
Cornwall
Operating from 2002 to Present
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
2002 24 34 0.121 Aug 13 0.117 Aug 14 0.101 July 22 0.099 Aug 11
2003 11 17 0.098 June 25 0.091 June 26 0.087 July 2 0.085 April 15
2004 7 9 0.099 July 22 0.086 June 24 0.084 Aug 10 0.083 May 13
2005 11 23 0.099 June 9 0.096 Aug 12 0.095 June 25 0.094 July 26
2006 13 21 0.100 June 19 0.094 June 18 0.089 June 22 0.085 July 10
2007 20 29 0.123 July 9 0.095 June 25 0.091 Aug 30 0.089 Sept 26
2008 4 9 0.090 April 19 0.081 June 10 0.079 April 18 0.077 June 13
2009 0 3 0.074 April 27 0.074 May 22 0.072 June 7 0.070 May 21
2010 2 5 0.087 May 1 0.083 Sep 2 0.074 Sep 1 0.072 July 12
2011 1 2 0.085 July 21 0.074 June 21 0.070 June 7 0.069 July 11
2012 3 6 0.079 July 13 0.079 July 17 0.079 Aug 9 0.073 April 16
2013 2 3 0.085 May 31 0.081 Sept 11 0.075 April 28 0.068 June 1
2014 1 1 0.079 June 17 0.069 May 12 0.068 May 27 0.066 June 2
2015 4 6 0.084 May 8 0.079 Sept 18 0.076 May 4 0.076 Aug 3
2016 4 7 0.091 May 26 0.081 May 25 0.079 Aug 25 0.078 May 27
2017 0 1 0.071 May 17 0.069 April 11 0.069 June 10 0.067 June 12
2018 1 4 0.080 July 2 0.075 July 16 0.072 May 2 0.071 May 25
2019 0 0 0.067 June 5 0.066 July 30 0.062 July 11 0.062 July 16
2020 0 0 0.065 June 9 0.064 June 10 0.064 July 22 0.063 June 25
2021 1 1 0.076 May 21 0.070 May 26 0.069 Aug 26 0.068 April 28
2022 0 3 0.073 Aug 20 0.071 May 21 0.071 Aug 4 0.070 July 28
Danbury
Operating from 1982 to Present
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1994 15 20 0.102 July 2 0.100 Aug 9 0.096 Aug 4 0.093 June 17
1995 14 17 0.122 July 13 0.097 Aug 1 0.094 July 4 0.093 June 30
1996 9 11 0.085 Aug 23 0.084 July 14 0.082 July 6 0.081 Aug 26
1997 19 22 0.112 June 30 0.107 June 25 0.106 July 27 0.105 Aug 10
1998 16 27 0.102 Aug 24 0.094 Aug 23 0.092 May 29 0.092 July 15
1999 22 25 0.115 July 17 0.111 July 16 0.111 July 29 0.106 May 31
2000 9 18 0.097 June 10 0.096 June 2 0.092 June 26 0.090 June 24
2001 22 25 0.112 June 19 0.107 June 20 0.098 Aug 2 0.096 July 22
2002 26 33 0.121 Aug 13 0.120 Aug 14 0.110 Aug 2 0.109 June 11
2003 12 14 0.103 June 25 0.088 June 29 0.086 June 26 0.085 July 2
2004 7 12 0.098 July 22 0.092 June 8 0.086 June 24 0.086 Aug 20
2005 16 22 0.110 June 26 0.109 Aug 12 0.106 July 27 0.104 July 26
2006 13 17 0.103 June 18 0.098 June 19 0.088 July 26 0.087 June 22
2007 18 25 0.108 July 9 0.100 Aug 3 0.098 July 10 0.092 June 26
2008 9 14 0.093 June 28 0.091 June 10 0.088 April 19 0.086 June 14
2009 3 7 0.083 May 22 0.080 Aug 18 0.076 July 16 0.074 Aug 4
2010 7 15 0.097 Sep 2 0.091 July 16 0.088 May 1 0.084 June 27
2011 6 10 0.089 July 21 0.086 June 9 0.083 June 21 0.083 July 6
2012 8 15 0.090 July 13 0.087 Aug 9 0.085 July 17 0.084 Aug 17
2013 4 10 0.088 Sept 11 0.079 May 31 0.076 June 21 0.076 June 76
2014 3 9 0.084 June 17 0.082 Aug 27 0.080 May 27 0.074 June 3
2015 6 15 0.088 Sept 18 0.084 May 8 0.080 Sept 8 0.079 June 12
2016 8 12 0.099 May 26 0.087 June 26 0.082 May 25 0.081 May 27
2017 1 8 0.078 May 17 0.075 Aug 3 0.074 June 30 0.072 May 18
2018 3 7 0.092 July 2 0.082 June 18 0.081 July 16 0.075 May 2
2019 0 6 0.075 July 16 0.075 July 30 0.074 Sept 22 0.072 July 27
2020 0 1 0.071 June 9 0.068 Aug 10 0.067 July 19 0.067 July 22
2021 0 4 0.075 May 26 0.074 Aug 26 0.072 Aug 6 0.071 June 7
2022 2 7 0.076 July 21 0.076 Aug 4 0.075 July 1 0.075 July 28
Greenwich
Operating from 1982 to Present
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1994 21 27 0.129 July 6 0.116 June 18 0.111 July 7 0.107 July 13
1995 19 23 0.122 July 14 0.108 Aug 1 0.106 Aug 2 0.102 June 19
1996 14 18 0.104 July 18 0.099 Aug 4 0.098 Aug 5 0.093 Aug 6
1997 20 26 0.138 July 15 0.118 July 14 0.103 June 21 0.101 July 17
1998 23 27 0.097 Aug 24 0.092 June 25 0.089 July 4 0.089 Aug 23
1999 17 24 0.119 July 16 0.114 July 18 0.113 July 17 0.107 July 24
2000 11 14 0.113 June 10 0.095 June 2 0.085 May 7 0.084 June 1
2001 22 25 0.131 Aug 7 0.117 Aug 9 0.107 July 25 0.098 June 19
2002 26 35 0.120 Aug 13 0.110 July 18 0.106 July 2 0.103 June 11
2003 15 21 0.124 June 26 0.106 June 25 0.105 June 24 0.099 Aug 21
2004 3 5 0.085 June 9 0.084 July 22 0.079 June 8 0.075 July 2
2005 17 22 0.110 Aug 13 0.099 Aug 11 0.093 July 27 0.089 July 26
2006 11 16 0.100 July 17 0.099 June 18 0.099 July 18 0.097 Aug 1
2007 10 19 0.093 July 17 0.090 June 26 0.085 June 1 0.084 June 27
2008 14 18 0.105 June 10 0.102 July 18 0.090 July 19 0.088 June 7
2009 1 3 0.079 Aug 15 0.073 July 16 0.072 Aug 4 0.068 Aug 10
2010 7 10 0.091 Sep 1 0.082 July 12 0.082 Aug 17 0.079 July 7
2011 8 11 0.093 June 8 0.087 June 7 0.086 July 7 0.081 Aug 20
2012 15 21 0.095 July 17 0.090 June 20 0.089 Aug 31 0.088 June 28
2013 8 11 0.089 May 30 0.083 July 18 0.082 July 19 0.082 Aug 21
2014 4 5 0.091 July 7 0.083 June 17 0.081 Aug 27 0.078 July 8
2015 9 14 0.091 Sept 17 0.089 Aug 15 0.086 June 11 0.084 July 29
2016 10 12 0.091 May 26 0.089 May 25 0.087 July 6 0.085 July 21
2017 3 4 0.090 June 12 0.086 May 18 0.084 July 20 0.074 May 17
2018 9 14 0.095 July 10 0.086 July 9 0.086 Aug 6 0.084 Aug 8
2019 5 8 0.086 July 4 0.086 July 16 0.084 July 29 0.084 July 30
2020 4 6 0.065 July 30 0.083 June 9 0.081 July 19 0.077 July 21
2021 8 11 0.094 Aug 26 0.082 June 6 0.078 June 30 0.078 Aug 6
2022 5 12 0.085 July 20 0.079 Aug 4 0.077 Aug 2 0.076 July 13
Groton
Operating from 1985 to Present, Relocated 2007
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1994 14 22 0.105 July 13 0.096 July 7 0.094 July 16 0.093 July 27
1995 10 13 0.119 July 19 0.113 Aug 21 0.113 July 14 0.101 June 18
1996 12 15 0.120 July 18 0.098 May 20 0.097 July 6 0.095 June 14
1997 23 25 0.153 July 15 0.125 July 14 0.107 June 25 0.104 Aug 2
1998 10 16 0.109 June 26 0.090 Sept 6 0.089 Aug 27 0.083 Aug 4
1999 20 25 0.132 June 7 0.104 June 23 0.103 July 6 0.096 May 30
2000 10 14 0.124 June 10 0.105 June 11 0.085 May 9 0.084 Aug 8
2001 15 19 0.099 Aug 7 0.095 Aug 1 0.090 Aug 2 0.090 Aug 8
2002 14 19 0.127 July 2 0.114 July 18 0.102 July 1 0.095 Aug 13
2003 11 16 0.113 June 26 0.112 June 27 0.104 June 25 0.095 July 5
2004 3 4 0.095 June 9 0.079 May 12 0.077 June 8 0.075 May 12
2005 10 13 0.093 Sept 12 0.088 June 8 0.086 April 20 0.085 Aug 11
2006 7 9 0.110 July 18 0.100 Aug 2 0.092 Aug 3 0.090 Aug 1
2007 5 19 0.095 May 25 0.090 July 8 0.089 June 28 0.089 Aug 3
2008 6 9 0.094 July 19 0.093 June 10 0.081 July 17 0.080 July 18
2009 1 5 0.083 Aug 18 0.075 Aug 15 0.074 Aug 26 0.073 Aug 17
2010 3 8 0.078 June 24 0.078 Sep 1 0.076 June 5 0.075 July 17
2011 9 11 0.088 July 22 0.085 July 23 0.083 July 18 0.082 June 7
2012 8 14 0.104 June 29 0.092 Aug 31 0.091 July 18 0.087 June 20
2013 6 7 0.091 July 19 0.090 June 25 0.086 June 24 0.085 May 30
2014 0 0 0.069 May 27 0.065 July 26 0.065 Aug 5 0.064 May 12
2015 6 12 0.086 June 11 0.080 Aug 31 0.079 July 29 0.077 Aug 15
2016 3 10 0.087 May 25 0.082 July 15 0.080 May 26 0.075 June 7
2017 4 6 0.090 May 18 0.090 June 13 0.081 June 12 0.078 June 11
2018 2 6 0.082 July 10 0.081 July 2 0.075 May 2 0.074 May 26
2019 3 7 0.079 June 29 0.079 July 4 0.076 Aug 8 0.075 July 28
2020 3 4 0.094 July 30 0.077 Aug 5 0.076 July 27 0.071 July 13
2021 3 6 0.079 June 5 0.076 Aug 13 0.076 Aug 26 0.075 Aug 7
2022 0 4 0.073 July 24 0.073 Aug 9 0.072 July 20 0.071 Aug 5
E. Hartford
Operating from 1982 to Present
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1994 19 27 0.135 June 18 0.103 July 2 0.103 Aug 9 0.099 July 20
1995 13 22 0.113 July 13 0.108 June 30 0.097 July 4 0.095 July 14
1996* 3 7 0.081 July 6 0.079 July 8 0.076 June 13 0.075 May 19
1997 11 14 0.137 June 25 0.124 June 21 0.098 June 30 0.097 Aug 10
1998 10 13 0.103 Aug 24 0.095 July 17 0.084 Aug 6 0.082 July 17
1999 16 19 0.105 July 17 0.099 July 16 0.095 June 1 0.094 July 29
2000 4 11 0.097 June 10 0.087 July 3 0.079 June 26 0.078 June 9
2001 15 22 0.114 June 20 0.102 June 19 0.096 July 23 0.093 Aug 9
2002 16 22 0.126 Aug 13 0.104 Aug 14 0.100 Aug 11 0.100 Aug 12
2003 5 8 0.084 June 26 0.083 June 25 0.077 June 27 0.077 July 4
2004 5 10 0.087 July 22 0.082 June 17 0.077 May 15 0.077 June 8
2005 12 13 0.103 July 27 0.095 July 26 0.091 June 9 0.088 June 8
2006 6 9 0.111 June 18 0.098 June 19 0.087 June 22 0.086 May 29
2007 9 16 0.107 Aug 3 0.100 July 9 0.097 June 27 0.097 July 10
2008 4 9 0.089 June 10 0.086 June 7 0.080 June 28 0.080 July 3
2009 1 3 0.076 April 28 0.073 May 22 0.071 Aug 18 0.066 April 25
2010 4 6 0.089 Sep 2 0.079 July 28 0.077 July 16 0.076 June 27
2011 3 5 0.092 July 21 0.081 June 21 0.080 July 11 0.072 June 6
2012 6 11 0.091 July 17 0.079 Sept 13 0.077 July 13 0.077 Aug 17
2013 4 7 0.086 Sept 11 0.078 July 19 0.077 May 31 0.077 June 21
2014 5 9 0.083 July 7 0.082 Aug 27 0.077 June 17 0.077 July 8
2015 3 8 0.084 Sept 18 0.079 May 8 0.076 Sept 7 0.075 Sept 8
2016 3 7 0.093 May 26 0.081 May 28 0.076 July 22 0.075 May 25
2017 1 4 0.078 May 17 0.075 May 18 0.072 June 10 0.071 June 30
2018 1 1 0.083 June 18 0.070 Aug 7 0.067 May 25 0.067 July 3
2019 3 5 0.077 July 16 0.077 July 19 0.077 Sept 22 0.072 July 30
2020 0 0 0.069 July 19 0.068 June 4 0.065 June 9 0.064 June 22
2021 0 1 0.074 June 7 0.069 Aug 11 0.068 Aug 26 0.066 May 26
2022 2 4 0.081 July 1 0.077 Aug 4 0.075 Aug 5 0.074 June 26

*Site did not meet 75% minimum data completeness requirement
Hamden
Operating from 1999 to 2003
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1999 18 24 0.117 July 24 0.115 July 17 0.109 July 16 0.105 July 18
2000 7 15 0.104 June 10 0.088 May 7 0.083 May 9 0.081 June 2
2001 15 23 0.110 Aug 9 0.104 June 30 0.102 Aug 7 0.101 July 25
2002 24 28 0.124 Aug 13 0.122 July 9 0.106 Aug 12 0.103 July 18
2003 9 12 0.105 July 4 0.096 June 25 0.092 July 26 0.091 June 24
Madison
Operating from 1982, relocated in 2012
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1994 18 29 0.123 July 13 0.115 June 18 0.097 Aug 9 0.093 July 6
1995 23 26 0.141 July 14 0.135 June 19 0.126 Aug 21 0.117 July 15
1996 15 20 0.107 July 18 0.103 July 6 0.098 July 16 0.095 June 14
1997 25 29 0.151 July 15 0.119 July 14 0.113 June 25 0.109 Aug 2
1998 15 25 0.107 June 26 0.105 June 25 0.097 Sept 6 0.097 Sept 27
1999 22 24 0.130 June 7 0.114 July 6 0.105 July 16 0.104 July 17
2000 16 18 0.121 June 10 0.104 June 11 0.093 June 9 0.087 Aug 27
2001 21 24 0.133 Aug 7 0.126 Aug 9 0.105 June 30 0.100 July 25
2002 31 36 0.134 July 2 0.126 July 18 0.114 Aug 13 0.110 July 9
2003 16 25 0.124 June 25 0.117 June 27 0.115 June 26 0.101 July 5
2004 5 8 0.111 June 9 0.086 June 8 0.084 July 20 0.077 June 15
2005 16 23 0.099 Aug 13 0.096 Sept 12 0.093 July 19 0.092 July 21
2006 8 14 0.114 July 18 0.100 Aug 2 0.095 June 18 0.095 Aug 3
2007 13 23 0.105 May 25 0.101 Aug 4 0.095 June 26 0.093 July 8
2008 7 10 0.105 July 19 0.092 July 18 0.085 June 10 0.078 July 17
2009 1 5 0.079 Aug 17 0.075 Aug 26 0.074 Aug 5 0.073 Aug 18
2010 7 14 0.082 July 4 0.081 July 17 0.080 July 6 0.079 July 5
2011 8 10 0.103 July 22 0.097 June 7 0.097 June 8 0.092 July 18
2012 11 15 0.100 Aug 31 0.099 June 29 0.093 June 20 0.090 June 21
2013 8 11 0.089 June 24 0.089 July 19 0.088 June 25 0.085 May 30
2014 0 2 0.074 July 22 0.074 May 27 0.070 July 31 0.069 July 28
2015 10 14 0.091 June 11 0.087 July 29 0.084 Aug 31 0.081 Aug 4
2016 7 10 0.089 May 25 0.086 May 26 0.082 July 18 0.080 Sept 14
2017 7 11 0.097 June 12 0.095 June 13 0.090 May 18 0.086 July 12
2018 5 13 0.087 Aug 29 0.086 July 10 0.080 May 26 0.077 July 1
2019 7 11 0.086 July 29 0.084 July 28 0.084 June 29 0.084 Aug 8
2020 4 12 0.095 July 30 0.088 July 27 0.085 Aug 5 0.080 July 28
2021 10 11 0.089 July 7 0.085 Aug 26 0.084 Aug 27 0.083 June 5
2022 3 5 0.078 July 20 0.077 July 24 0.076 Aug 2 0.075 Aug 9
Middletown
Operating from 1982, relocated in 2018
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1994 22 31 0.135 June 18 0.109 Aug 9 0.104 July 13 0.102 July 6
1995 23 30 0.123 July 14 0.123 Aug 1 0.110 July 13 0.102 Aug 2
1996 9 14 0.096 Aug 23 0.092 Aug 6 0.090 July 18 0.089 July 6
1997 18 20 0.145 June 25 0.113 June 21 0.108 June 30 0.103 June 12
1998 20 25 0.114 Aug 24 0.098 Sept 6 0.089 July 15 0.089 Sept 27
1999 20 25 0.128 July 16 0.122 July 24 0.113 July 17 0.107 July 15
2000 14 19 0.103 June 10 0.092 May 9 0.090 May 7 0.089 June 2
2001 22 28 0.111 June 30 0.111 Aug 9 0.108 Aug 2 0.102 June 19
2002 27 33 0.126 July 9 0.110 June 11 0.110 June 23 0.110 Aug 13
2003 12 16 0.111 July 4 0.096 June 24 0.093 June 27 0.092 June 25
2004 7 16 0.102 June 8 0.084 July 22 0.083 Aug 28 0.082 Aug 20
2005 16 21 0.110 June 25 0.106 June 26 0.099 Aug 13 0.096 July 26
2006 11 19 0.110 June 18 0.098 July 17 0.094 June 22 0.089 June 19
2007 15 25 0.111 June 26 0.101 June 27 0.099 Aug 3 0.093 July 9
2008 8 12 0.091 June 7 0.083 June 10 0.083 July 26 0.082 July 8
2009 1 3 0.081 April 28 0.075 Aug 18 0.071 Aug 4 0.070 April 27
2010 6 9 0.086 Sep 2 0.083 June 27 0.081 July 16 0.081 Aug 9
2011 6 6 0.090 July 11 0.088 July 6 0.087 June 8 0.080 June 7
2012 12 15 0.098 July 17 0.088 Aug 31 0.085 July 14 0.081 Sep 13
2013 6 8 0.097 June 25 0.086 May 30 0.085 July 19 0.082 May 31
2014 7 11 0.086 May 27 0.082 July 8 0.082 July 22 0.080 Aug 27
2015 7 12 0.084 Sept 17 0.082 Sept 18 0.079 Sept 8 0.078 May 8
2016 7 13 0.100 July 22 0.091 May 26 0.084 July 18 0.080 May 25
2017 6 8 0.086 May 18 0.085 June 12 0.081 May 17 0.079 June 11
2018 5 8 0.078 May 2 0.077 Aug 28 0.077 May 25 0.077 July 10
2019 6 7 0.087 July 16 0.082 July 29 0.077 July 19 0.076 July 30
2020 1 2 0.079 July 19 0.071 Aug 21 0.069 June 4 0.069 Aug 10
2021 7 11 0.086 June 5 0.079 Aug 12 0.079 Aug 26 0.078 June 30
2022 2 6 0.084 Aug 4 0.080 Aug 5 0.074 July 1 0.073 Aug 2
New Haven
Operating from 1982 to 1999, Restarted 2004
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1994 6 13 0.116 June 18 0.100 July 2 0.087 July 13 0.083 July 6
1995 7 10 0.107 June 14 0.098 Aug 1 0.095 Aug 2 0.092 June 18
1996 3 5 0.088 July 6 0.099 Aug 6 0.076 Aug 23 0.072 Aug 4
1997 12 14 0.102 July 15 0.099 June 25 0.092 June 21 0.089 Aug 2
1998 6 6 0.088 Aug 24 0.088 Sept 6 0.085 July 4 0.079 July 3
1999 12 13 0.105 July 17 0.099 July 16 0.095 June 1 0.094 July 29
2004 3 5 0.085 July 22 0.078 June 9 0.077 July 17 0.073 July 8
2005 7 9 0.108 Aug 13 0.085 Aug 12 0.084 June 25 0.080 June 26
2006 6 8 0.100 June 18 0.083 July 4 0.080 July 2 0.079 Aug 1
2007 6 9 0.087 May 25 0.087 July 17 0.085 June 2 0.082 July 9
2008 2 6 0.084 June 28 0.080 July 26 0.074 June 14 0.074 Aug 18
2009 0 1 0.071 Aug 15 0.065 July 17 0.063 Aug 16 0.062 April 28
2010 1 2 0.076 June 27 0.073 May 1 0.070 July 17 0.068 June 4
2011 6 9 0.098 July 11 0.085 June 8 0.083 June 7 0.080 July 22
2012 13 21 0.096 Aug 31 0.090 July 14 0.089 July 1 0.081 July 17
2013 3 9 0.084 May 31 0.077 June 25 0.077 July 19 0.075 June 7
2014 2 5 0.078 June 17 0.076 July 8 0.075 Aug 27 0.072 May 27
2015 6 7 0.093 June 11 0.088 Sept 17 0.084 Aug 15 0.081 Aug 17
2016 3 10 0.091 July 22 0.084 May 26 0.080 July 21 0.075 June 23
2017 3 5 0.089 June 12 0.085 May 18 0.079 July 20 0.075 June 11
2018 3 4 0.088 July 10 0.085 July 16 0.082 May 26 0.072 Aug 8
2019 4 7 0.089 July 16 0.086 July 29 0.081 July 28 0.078 Sept 22
2020 3 3 0.082 July 19 0.078 Aug 24 0.076 July 30 0.068 June 20
2021 3 4 0.081 July 7 0.078 Aug 7 0.076 June 5 0.071 June 30
2022 2 5 0.080 Aug 5 0.077 Aug 4 0.072 June 26 0.072 July 20
Stafford
Operating from 1982 to Present
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1994 19 27 0.109 Aug 9 0.101 July 2 0.100 Aug 4 0.097 July 20
1995 12 20 0.114 July 13 0.108 June 30 0.101 Sept 7 0.094 Aug 31
1996 9 15 0.100 Aug 7 0.084 July 8 0.083 June 8 0.083 July 9
1997 12 23 0.142 June 25 0.128 June 21 0.099 Aug 10 0.097 June 30
1998 19 27 0.118 Aug 24 0.114 July 15 0.101 July 16 0.098 May 29
1999 20 24 0.101 Aug 17 0.098 June 1 0.095 June 24 0.091 May 31
2000 6 14 0.098 June 10 0.084 July 3 0.081 June 26 0.079 June 16
2001 18 22 0.122 June 20 0.118 June 19 0.108 July 23 0.102 July 24
2002 25 31 0.116 Aug 13 0.112 June 11 0.111 Aug 14 0.102 Aug 11
2003 6 9 0.085 June 25 0.082 June 27 0.082 July 4 0.081 July 2
2004 6 10 0.089 May 15 0.085 Aug 20 0.083 July 22 0.081 Aug 3
2005 12 19 0.106 June 26 0.101 July 27 0.099 June 9 0.097 June 25
2006 8 15 0.105 June 18 0.100 June 22 0.096 June 19 0.089 Aug 7
2007 18 22 0.107 Aug 3 0.101 June 27 0.100 July 9 0.087 June 25
2008 7 13 0.094 June 10 0.087 June 7 0.087 July 3 0.084 July 8
2009 3 6 0.082 April 28 0.081 May 22 0.079 Aug 18 0.074 Aug 4
2010 6 15 0.101 Sep 2 0.087 July 28 0.082 Aug 9 0.079 July 16
2011 1 3 0.087 July 11 0.072 July 21 0.072 June 21 0.068 July 6
2012 8 19 0.096 July 17 0.086 May 13 0.085 Sept 13 0.083 Aug 17
2013 5 7 0.084 Sept 11 0.083 May 31 0.082 June 21 0.081 June 1
2014 5 9 0.082 July 7 0.081 June 2 0.077 June 17 0.077 July 8
2015 2 6 0.079 Sept 17 0.079 Sept 18 0.074 May 8 0.072 May 4
2016 1 5 0.082 May 26 0.074 May 25 0.073 May 28 0.072 July 22
2017 2 3 0.084 May 17 0.077 May 18 0.072 June 10 0.070 June 30
2018 1 4 0.082 June 18 0.073 May 2 0.071 May 25 0.071 Aug 7
2019 1 4 0.078 July 19 0.075 July 16 0.075 Sept 22 0.073 July 30
2020 0 0 0.068 June 4 0.066 July 19 0.063 Aug 11 0.063 June 25
2021 0 1 0.071 May 26 0.069 Aug 11 0.068 Aug 26 0.067 May 21
2022 1 2 0.077 Aug 4 0.074 July 1 0.068 Aug 5 0.068 Aug 20
Stratford
Operating from 1982 to Present
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1994 21 32 0.129 June 18 0.126 July 13 0.101 July 2 0.093 July 25
1995 18 21 0.130 July 14 0.117 Aug 1 0.117 June 19 0.115 Aug 21
1996 12 20 0.107 Aug 5 0.097 Aug 6 0.096 July 6 0.096 July 18
1997 26 31 0.143 July 15 0.123 July 14 0.106 July 17 0.103 Aug 2
1998 25 33 0.109 June 25 0.106 Aug 24 0.100 June 26 0.097 Aug 29
1999 17 25 0.133 June 7 0.104 July 16 0.100 July 17 0.096 July 15
2000 11 17 0.124 June 10 0.094 June 11 0.091 May 7 0.090 June 2
2001 18 29 0.131 Aug 7 0.120 Aug 9 0.110 July 25 0.102 June 30
2002 29 35 0.129 July 2 0.115 July 18 0.104 Aug 13 0.103 Aug 12
2003 15 24 0.125 June 25 0.114 June 26 0.106 July 4 0.101 June 27
2004 7 13 0.110 June 9 0.088 July 21 0.081 May 11 0.081 June 8
2005 13 20 0.096 Aug 11 0.096 Aug 13 0.092 July 21 0.090 Sept 12
2006 14 16 0.110 July 17 0.099 July 18 0.097 June 18 0.095 Aug 2
2007 15 23 0.095 June 26 0.094 July 17 0.093 Aug 2 0.092 May 25
2008 6 16 0.103 July 19 0.094 July 18 0.083 July 16 0.078 July 26
2009 2 8 0.084 Aug 15 0.081 Aug 17 0.073 April 28 0.073 Aug 16
2010 9 18 0.080 July 5 0.080 July 17 0.080 Sep 1 0.079 July 4
2011 8 13 0.095 June 8 0.092 June 7 0.088 July 11 0.087 July 7
2012 15 19 0.097 June 20 0.095 Aug 31 0.093 July 1 0.090 June 29
2013 10 17 0.094 May 30 0.091 June 25 0.090 July 18 0.090 July 19
2014 3 8 0.084 May 27 0.078 July 22 0.076 June 17 0.074 July 7
2015 10 15 0.095 June 11 0.094 Sept 17 0.086 Aug 15 0.086 Aug 17
2016 10 14 0.096 July 22 0.089 May 25 0.084 July 15 0.083 July 18
2017 7 11 0.095 June 12 0.091 May 18 0.088 June 13 0.081 July 20
2018 8 14 0.099 July 10 0.090 Aug 29 0.087 Aug 28 0.083 May 26
2019 7 10 0.087 July 29 0.084 July 16 0.083 July 28 0.084 July 4
2020 4 8 0.087 July 30 0.083 July 19 0.080 July 27 0.076 Aug 5
2021 8 13 0.091 July 7 0.087 July 16 0.087 Aug 26 0.086 June 5
2022 5 10 0.086 July 20 0.085 Aug 5 0.082 Aug 2 0.081 Aug 4
Torrington
Operating from 1991 to 2000
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1994 11 24 0.100 Aug 4 0.098 July 20 0.096 Aug 9 0.095 July 2
1995 13 22 0.107 July 13 0.102 Aug 31 0.099 Sept 7 0.095 July 4
1996 10 16 0.096 Aug 7 0.096 Aug 8 0.092 July 8 0.092 June 8
1997 13 18 0.099 Aug 11 0.098 Aug 10 0.097 July 27 0.097 June 21
1998 19 25 0.098 May 29 0.098 July 14 0.098 July 15 0.097 Aug 24
1999 24 31 0.103 July 31 0.102 July 16 0.100 Aug 17 0.098 July 29
2000 9 12 0.097 June 10 0.087 June 2 0.086 June 26 0.085 June 24
Westport
Operating from 1996 to Present
Year # Days > 1st High (ppm) Date 2nd High (ppm) Date 3rd High (ppm) Date 4th High (ppm) Date
0.075 0.070
1996 14 22 0.111 July 18 0.108 Aug 5 0.099 July 6 0.097 July 17
1997 23 26 0.141 July 15 0.118 July 14 0.111 June 21 0.109 July 17
1998 19 27 0.106 June 25 0.106 Aug 24 0.093 Aug 30 0.089 July 13
1999 22 25 0.121 July 16 0.117 June 7 0.113 July 17 0.111 July 18
2000 11 12 0.120 June 10 0.089 May 6 0.085 June 2 0.084 May 7
2001 19 27 0.133 Aug 7 0.122 Aug 9 0.114 July 25 0.097 May 4
2002 30 33 0.117 July 18 0.114 Aug 12 0.111 July 2 0.109 July 9
2003 13 18 0.113 June 26 0.112 June 25 0.108 July 4 0.097 Aug 21
2004 8 13 0.099 June 9 0.087 July 22 0.082 June 8 0.081 July 2
2005 16 23 0.100 Aug 13 0.092 July 26 0.091 July 21 0.088 Aug 11
2006 14 20 0.119 June 18 0.109 July 17 0.102 July 18 0.089 June 22
2007 8 14 0.096 June 26 0.093 May 25 0.085 June 1 0.083 June 27
2008 10 15 0.103 July 19 0.095 July 18 0.093 June 7 0.090 June 10
2009 2 5 0.085 Aug 17 0.082 Aug 15 0.073 April 28 0.073 Aug 16
2010 10 13 0.087 Sep 1 0.083 July 12 0.079 July 5 0.079 July 21
2011 9 14 0.101 June 8 0.092 June 7 0.087 June 9 0.087 July 7
2012 14 19 0.093 July 17 0.092 Aug 31 0.091 July 1 0.089 June 20
2013 12 15 0.099 July 19 0.095 May 30 0.087 June 25 0.086 July 18
2014 7 9 0.088 Aug 27 0.084 June 17 0.082 July 8 0.081 July 7
2015 10 16 0.096 Sept 17 0.092 June 11 0.092 Aug 17 0.087 Aug 15
2016 11 16 0.097 July 22 0.090 May 26 0.087 May 25 0.087 July 21
2017 5 9 0.097 June 12 0.090 May 18 0.090 July 20 0.081 June 13
2018 9 12 0.094 July 10 0.084 May 26 0.084 Aug 8 0.084 Aug 28
2019 5 11 0.090 July 16 0.088 July 29 0.084 July 4 0.081 July 28
2020 3 6 0.083 July 19 0.077 July 25 0.077 July 30 0.073 July 27
2021 10 12 0.099 Aug 26 0.089 July 7 0.087 July 16 0.086 June 6
2022 6 14 0.088 Aug 5 0.082 June 26 0.082 July 20 0.081 Aug 4

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