Monthly mean water levels

Monthly mean water level in metres referred to chart datum.

Lakes Superior Huron St.Clair Erie Ontario
2009 January -0.06 0.01 0.55 0.55 0.56
  February -0.10 0.01 0.55 0.57 0.62
  March -0.12 0.09 0.66 0.82 0.72
  April -0.07 0.20 0.74 0.92 0.92
  May 0.05 0.34 0.80 0.96 0.99
  June 0.10 0.41 0.85 0.95 0.96
  July 0.14 0.44 0.84 0.92 0.92
  August 0.19 0.44 0.80 0.85 0.83
  September 0.21 0.37 0.73 0.74 0.58
  October 0.16 0.29 0.59 0.63 0.40
  November 0.15 0.27 0.53 0.57 0.30
  December 0.10 0.22 0.47 0.52 0.28
2010 January 0.01 0.15 0.34 0.49 0.31
  February -0.06 0.11 0.04 0.42 0.34
  March -0.11 0.09 0.36 0.47 0.35
  April -0.12 0.11 0.49 0.59 0.46
  May -0.12 0.13 0.58 0.71 0.51
  June -0.07 0.20 0.67 0.82 0.65
  July -0.01 0.26 0.68 0.77 0.77
  August 0.0 0.24 0.65 0.69 0.70
  September 0.02 0.16 0.52 0.52 0.52
  October -0.01 0.07 0.45 0.47 0.41
  November -0.06 -0.04 0.32 0.38 0.30
  December -0.13 -0.14 0.31 0.36 0.32
2011 January -0.08 -0.19 0.08 0.33 0.29
  February -0.27 -0.22 0.10 0.25 0.21
  March -0.33 -0.19 0.27 0.53 0.41
  April -0.29 -0.09 0.49 0.70 0.65
  May -0.16 0.1 0.75 0.96 1.03
  June -0.05 0.21 0.82 1.08 1.13
  July 0.05 0.26 0.81 0.98 0.94
  August 0.08 0.24 0.76 0.88 0.74
  September 0.03 0.13 0.24 0.80 0.56
  October 0.01 0.08 0.62 0.77 0.46
  November -0.04 0.07 0.55 0.71 0.38
  December -0.11 0.04 0.08 0.90 0.42
2012 January -0.19 -0.01 0.62 0.88 0.60
  February -0.26 -0.04 0.59 0.87 0.79
  March -0.27 0.00 0.55 0.86 0.77
  April -0.2 0.03 0.59 0.81 0.72
  May -0.14 0.05 0.58 0.77 0.71
  June 0.00 0.07 0.58 0.72 0.70
  July 0.10 0.04 0.54 0.64 0.59
  August 0.07 -0.03 0.45 0.54 -0.34
  September 0.00 -0.14 0.35 0.45 0.30
  October -0.07 -0.26 0.21 0.33 0.14
  November -0.09 -0.33 0.19 0.35 0.09
  December -0.14 -0.39 0.14 0.32 0.08
2013 January -0.21 -0.43 0.12 0.32 0.18
  February -0.24 -0.39 0.14 0.36 0.32
  March -0.29 -0.37 0.24 0.42 0.38
  April -0.28 -0.25 0.36 0.52 0.52
  May -0.09 -0.07 0.44 0.60 0.68
  June 0.06 0.05 0.59 0.73 0.90
  July 0.17 0.09 0.85 0.94 0.66
  August 0.24 0.08 0.62 0.78 0.79
  September 0.28 0.04 0.56 0.66 0.59
  October 0.25 0.01 0.45 0.57 0.42
  November 0.20 -0.01 0.39 0.47 0.40
  December 0.15 -0.03 0.39 0.44 0.33
2014 January 0.09 -0.04 0.29 0.50 0.44
  February 0.04 -0.05 0.20 0.44 0.41
  March 0.04 -0.05 0.20 0.44 0.41
  April 0.07 0.06 0.56 0.70 0.63
  May 0.27 0.27 0.73 0.85 0.94
  June 0.40 0.38 0.81 0.90 0.97
  July 0.46 0.46 0.86 0.90 0.89
  August 0.47 0.48 0.86 0.87 0.76
  September 0.50 0.51 0.86 0.81 0.58
  October 0.51 0.54 0.78 0.75 0.39
  November 0.47 0.54 0.70 0.65 0.26
  December 0.40 0.53 0.73 0.67 0.26
2015 January 0.34 0.51 0.55 0.66 0.36
  February 0.27 0.50 0.34 0.53 0.30
  March 0.22 0.48 0.53 0.49 0.21
  April 0.24 0.52 0.77 0.71 0.42
  May 0.33 0.59 0.82 0.81 0.61
  June 0.43 0.68 1.02 1.02 0.81
  July 0.48 0.73 1.16 1.24 1.01
  August 0.48 0.72 1.08 1.12 0.91
  September 0.49 0.70 1.02 1.00 0.71
  October 0.40 0.58 0.86 0.84 0.47
  November 0.38 0.54 0.72 0.72 0.36
  December 0.39 0.55 0.72 0.67 0.27
2016 January 0.35 0.57 0.78 0.73 0.43
  February 0.29 0.56 0.77 0.77 0.62
  March 0.26 0.61 0.92 0.91 0.77
  April 0.28 0.77 1.09 1.10 0.91
  May 0.30 0.82 1.10 1.15 0.89
  June 0.41 0.84 1.11 1.11 0.82
  July 0.49 0.84 1.09 1.04 0.75
  August 0.50 0.82 1.06 0.96 0.64
  September 0.50 0.78 1.01 0.89 0.50
  October 0.48 0.69 0.92 0.83 0.34
  November 0.39 0.59 0.79 0.76 0.28
  December 0.34 0.51 0.72 0.67 0.26
2017 January 0.27 0.47 0.79 0.79 0.42
  February 0.23 0.48 0.82 0.90 0.62
  March 0.19 0.53 0.89 0.98 0.80
  April 0.21 0.66 1.07 1.14 1.15
  May 0.36 0.80 1.21 1.32 1.60
  June 0.47 0.88 1.24 1.33 1.61
  July 0.55 0.99 1.30 1.31 1.49
  August 0.58 1.00 1.26 1.20 1.23
  September 0.60 0.93 1.18 1.08 0.88
  October 0.61 0.87 1.06 0.96 0.66
  November 0.58 0.85 1.04 0.96 0.67
  December 0.52 0.79 0.96 0.90 0.57
2018 January 0.45 0.73 0.84 0.88 0.63
  February 0.38 0.74 0.92 0.94 0.70
  March 0.34 0.76 1.11 1.18 0.73
  April 0.27 0.79 1.20 1.27 0.81
  May 0.30 0.92 1.28 1.38 1.06
  June 0.36 0.98 1.32 1.39 1.02
  July 0.45 0.98 1.31 1.32 0.86
  August 0.45 0.95 1.24 1.22 0.71
  September 0.50 0.94 1.22 1.16 0.54
  October 0.57 0.90 1.12 1.07 0.42
  November 0.56 0.86 1.10 1.08 0.42
  December 0.47 0.83 1.07 1.10 0.51
2019 January 0.42 0.81 1.01 1.13 0.63
  February 0.38 0.83 1.01 1.11 0.77
  March 0.37 0.86 1.16 1.15 0.77
  April 0.41 0.96 1.30 1.33 0.95
  May 0.57 1.17 1.49 1.55 1.50
  June 0.64 1.32 1.59 1.64 1.71
  July 0.66 1.37 1.64 1.63 1.60
  August 0.66 1.32 1.56 1.52 1.33
  September 0.66 1.27 1.46 1.37 1.04
  October 0.68 1.29 1.37 1.24 0.84
  November 0.61 1.26 1.31 1.18 0.84
  December 0.54 1.25 1.28 1.18 0.80
2020 January 0.51 1.26 1.40 1.30 0.85
  February 0.44 1.25 1.39 1.40 0.92
  March 0.37 1.22 1.43 1.45 0.98
  April 0.42 1.30 1.51 1.55 1.12
  May 0.44 1.38 1.58 1.58 1.16
  June 0.50 1.45 1.62 1.60 1.09
  July 0.56 1.46 1.63 1.55 0.98
  August 0.61 1.42 1.57 1.43 0.85
  September 0.59 1.34 1.48 1.33 0.65
  October 0.56 1.25 1.34 1.22 0.50
  November 0.51 1.20 1.25 1.15 0.40
  December 0.43 1.14 1.23 1.15 0.42
2021 January 0.34 1.07 1.22 1.19 0.42
  February 0.26 0.99 1.07 1.07 0.33
  March 0.22 0.95 1.14 1.08 0.29
  April 0.28 0.95 1.14 1.13 0.42
  May 0.31 0.95 1.17 1.18 0.52
  June 0.35 0.93 1.22 1.21 0.51
  July 0.36 1.00 1.33 1.31 0.61
  August 0.34 1.02 1.31 1.29 0.65
  September 0.31 0.93 1.24 1.17 0.59
  October 0.29 0.91 1.21 1.17 0.58
  November 0.18 0.77 1.08 1.13 0.66
  December 0.11 0.69 1.02 1.08 0.67
2022 January 0.04 0.60 0.92 1.04 0.66
  February -0.03 0.54 0.67 0.93 0.68
  March -0.05 0.53 0.92 1.03 0.79
  April 0.04 0.66 1.00 1.09 0.93
  May 0.24 0.75 1.10 1.17 0.97
  June 0.37 0.80 1.15 1.18 0.93
  July 0.42 0.81 1.13 1.12 0.75
  August 0.45 0.79 1.10 1.05 0.54
  September 0.45 0.71 1.01 0.96 0.35
  October 0.40 0.60 0.85 0.82 0.21
  November 0.40 0.55 0.74 0.75 0.20
  December 0.37 0.46 0.72 0.70 0.27
2023 January 0.32 0.43 0.75 0.78 0.45
  February 0.26 0.41 0.77 0.86 0.56
  March 0.23 0.43 0.90 1.04 0.68
  April 0.28 0.56 1.02 1.14 0.93
  May 0.47 0.69 1.05 1.15 1.16
  June 0.48 0.68 1.06 1.10 1.04
  July 0.48 0.70 1.10 1.10 0.94
  August 0.47 0.70 1.12 1.09 0.86
  September 0.43 0.64 1.04 1.05 0.68
  October 0.35 0.56 0.88 0.89 0.46
  November 0.26 0.51 0.77 0.79 0.29
  December 0.17 0.44 0.73 0.76 0.29

Elevation of chart datum in metres referred to International Great Lakes Datum 1985.

Lake   Superior Huron St. Clair Erie Ontario
Chart Datum IGLD 1985 183.2 176.0 174.4 173.5 74.2