DISSOLVED OXYGEN

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 milligrams per liter. For details about the data, press here.

The highest reading, 18.1, occurred in 1/85, and the lowest, 7.6, in 9/93. All of the readings above 14.6 (10 percent of the samples), are shown in blue and all that are below 9.3 (another 10 percent), are in red.

 Averages by
Season and by
5-year Period:
 
(Overall = 12.0)
Jan-Mar14.0
Apr-Jun 11.1
Jul-Sep 10.4
Oct-Dec 13.0
1980-84 12.0
1985-89 12.3
1990-94 12.2
1995-99 11.8

YearJanFebMar AprMayJunJulAug SepOctNovDec
1980                   11.9 12.2 11.1
1981 14 13.8 13.7 11.9 10.1 7.8 12.2 9.2 10.9 10.4 14.8 16.2
1982 15.2 10.2 13 13.2 12.6 10 9.5 7.8 9.8 15 13.8 15.1
1983 13.3   13.3 12.8 11.6 10.1 10.1 8.6 11.8 11.6 13.4 13.8
14.8
1984 16.2   15.5 12.8 10.2 10.2 10.2 9.0 10.2 10.2 13.2 13.4
1985 18.1   13.1 12.7 9.6 9.8 11.8
11.8		 10 10.5 12.2 12.7 15
1986 15.2   13.4 10 10.6 9.8 10.6 12.2 10 13.9 14.3 13.2
1987 14.3   13.7 11.4 10.6 10.1 9.7 12.4 12.4 13.7 11.4 13.2
1988 13.9   12.7 12.4
12.2		 10.7
9.8		 9.8
11.4		 9.9
10.2		 12
13.5		 11.8 12.4
12.6		 12.2 14.6
1989 14.9 15.2
13.2		 15
12.4		 13.2
13.5		 10.8
8.4		 9.7
9.3		 9.4
9.8		 9.0
12.4		 11.2
9.0		 10.3 12.7 14.6
1990 12.6
9.1		 14
15.5		 12.6
12.4		 13.4
12.2		 11.8
11.1		 10.4
10		 9.5
9.42		 9.0
11.8		 9.9
11.8		 12
10.3		 13.2
13.6		 13
14
1991 14   12.3 13   10.2 12.6 11.7 11.7 11.3 13.8 14.2
1992 15   14.2 12.8 14.8 9.9 9.3 9.9 14 12.3
12		   14.6
1993   15.7 14.4
13.8		 12.4
11.54
10.6
11.9		 10.8
9.9
10.8
9.2		 9.8
9.6
10.2
9.3
10		 8.6
9.2
9.98		 9.98
10.1
9.98		 7.6
9.8
9.8
10
9.3		 9.8
11
14.2
12.4		 13
13		 12.7
13
1994 15 15
14.3		 15
15
13.1		 11.6
11.1
11.8
11.8		 10
11.2
10.2
10.7
12.8		 12
9.8
8.8
8.0
9.4		 13.3
10.8
11
10.9		 11.1
10.4
10.2
10.6
8.9
11.1		 10 13.0 13.9 11.9
1995 13.8 14.9 11.5 14.0 11.5 9.4 10.7
9.4		 11.5 10.0 12.0    
1996 14.0 14.8   10.9   8.8 8.4 9.6 10.3 10.5   13.5
1997   14.2   12.0 12.4
11.6		 11.2 10.0
10.0
9.1		 9.0
9.0
10.8		 9.4
9.4
9.0
9.0
9.9