pH, LAB MEASUREMENT

The measurements shown below were made at USGS station 01209710, located on the Norwalk River near the Perry Avenue bridge. All of the measurements are in standard pH units. For details about the data, press here.

The highest reading, 8.9, occurred in 8/86, and the lowest, 6.8, in 10/84. All of the readings above 8.2 (12 percent of the samples), are shown in blue and all that are below 7.2 (another 14 percent), are in red.

 Averages by
Season and by
5-year Period:
 
(Overall = 7.73)
Jan-Mar7.62
Apr-Jun 7.77
Jul-Sep 7.91
Oct-Dec 7.61
1980-84 7.53
1985-89 7.89
1990-94 7.71
1995-99 0.000

YearJanFebMar AprMayJunJulAug SepOctNovDec
1980                   7.4 7.2 7.5
1981 7.6 7.5 7.6 7.5 7.8 7.6 8.0 7.7 8.0 8.1 7.9 7.3
1982 7.4 7.5 7.5 8.0 8.1 7.3 7.6 7.5 7.8 8.0 7.6 7.4
1983 7.3   7.2 7.3 7.5 7.5 7.7 7.8 8.2 7.1 7.4 6.9
1984 7.3   7.2 7.2 7.6 7.7 7.4 7.6 7.2 6.8 7.4 7.5
1985 7.4   7.6 7.6 7.4 7.6 7.8 7.6 7.4 7.5 7.0 8.0
1986 8.2   8.2 8.1 7.9 8.1 8.1 8.9 7.9 8.3 7.8 7.7
1987 7.5   7.47 8.03 7.8 8.1 8.1 8.9 8.5 8.5 8.2 8.0
1988 7.8   8.0 7.8 7.8 8.4 7.7 8.1 8.3 8.5 7.8 7.6
1989     8.3 8.0 7.9 7.6 8.1 7.8 8.2 7.5 7.6 7.6
1990 7.7   8.0 8.5 8.3 7.9 7.9 7.6 8.4 7.3 7.8 7.6
1991 7.8   8.3 8.6   8.0 8.5 8.1 8.4 7.8 7.7 7.7
1992 7.8   7.6 7.8 8.0 7.5 7.7 7.6 7.8 7.6   7.6
1993   7.6 7.2
7.4
7.3
6.9
7.6
7.3
7.4
7.7
8.0
7.6
7.8
7.2
7.2
7.5
7.3
7.9
8.6
7.5
7.3
7.9
7.7
8.4
7.4
7.8
7.2
7.5
7.2
7.6
7.1
7.6
7.4
7.3
7.9
7.1
6.8
1994 7.6 7.0
7.3
7.5
6.9
6.8
7.4
7.5
7.1
7.9
7.3
7.7
8.3
7.0
7.6
7.3
7.2
6.9
7.1
7.2
7.4
7.8
7.7
7.9
8.0
7.4
7.8
7.3
7.8
7.6