FINAL REPORT - International Joint Commission

21: Lac St. Louis annual water levels for the 50,000-year stochastic sequence for Plan 1958-DD. . 46
22: Lac St. Louis annual water levels for the 50,000-year stochastic sequence for Plan A + . . . . . 46
23: Lac St. Louis annual water levels for the 50,000-year stochastic sequence for Plan B + . . . . . 46
24: Lac St. Louis annual water levels for the 50,000-year stochastic sequence for Plan D + . . . . . 46
25: Montreal Harbour annual water levels for the 50,000-year stochastic sequence
for Plan 1958-DD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
26: Montreal Harbour annual water levels for the 50,000-year stochastic sequence for Plan A + . . 47
27: Montreal Harbour annual water levels for the 50,000-year stochastic sequence for Plan B + . . 47
28: Montreal Harbour annual water levels for the 50,000-year stochastic sequence for Plan D + . . 47
29: Lake Ontario water levels: average, 1% exceedance and 99% exceedance
based on the 50,000-year year stochastic simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
30: Long Sault water levels: average, 1% exceedance and 99% exceedance based on
the 50,000-year year stochastic simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
31: Lake Ontario outflows: average, 1% exceedance and 99% exceedance based on
the 50,000-year year stochastic simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
32: Lac St. Louis water levels: average, 1% exceedance and 99% exceedance based on
the 50,000-year year stochastic simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
33: Montreal Harbour water levels: average, 1% exceedance and 99% exceedance based on
the 50,000-year year stochastic simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
34: Economic benefits by region based on stochastic analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
35: Environmental benefit ratios by sector based on historical analysis . . . . . . . . . . . . . . . . . . . . 62
36: Net economic benefits over the 101 year historical sequence for Plan D + at Lac St. Louis. . . 64
37: Downstream flood damages under Plan A + relative to 1958-DD based on stochastic analysis . 65
38: Cumulative erosion (m) after 25 years for all plans, based on stochastic analysis,
for a sample property in a high erosive area in Monroe County, NY . . . . . . . . . . . . . . . . . . . . 66
39: Wetland plant community zones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
40: Lake Ontario meadow marsh frequency distribution for the 50,000-year
stochastic simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
41: Lake Ontario emergent marsh frequency distribution for the 50,000-year
stochastic simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
42: Five-year moving average of the net total supply (NTS) for the four stochastic centuries
(S1-S4) and the historical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
43: Lake Ontario levels under Plan A + (blue) versus 1958-DD (red) for the 101-year
extremely dry stochastic sequence (S1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
44: Lake Ontario levels under Plan B + (blue) versus 1958-DD (red) for the 101-year
stochastic sequence with the longest drought (S4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
45: Lake Ontario levels under Plan D + (blue) versus 1958-DD (red) for the 101-year
stochastic sequence with the wettest supplies and biggest range (S2). . . . . . . . . . . . . . . . . . 77
46: Five-year moving average of the net total supply (NTS) sequences for the four
climate change scenarios (C1-C4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
47: Schematic of Information Management Strategy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
List of Tables
1: Key Environmental Performance Indicators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2: Economic Performance Indicators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
3: Differences in Absolute Damages between the Historic Sequence and 50,000 year
Stochastic Sequence under Plan 1958-DD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
4: Summary Results (economic results determined from stochastic, environmental ratios
based on historical supply sequence) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
5: Summary Economic Impacts based on Historical Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
6: Economic Results by Interest and Region (based on stochastic supply sequence) . . . . . . . . 55
7: Percent Damage by Performance Indicator Relative to an Economic Baseline . . . . . . . . . . . . 58
8: Environmental Performance Indicator Results (Ratios) based on Historical Supplies. . . . . . . 60
9: Shore Protection Maintenance, by Lake Ontario County, based on the
Stochastic Supply Simulation (average annual values (in million U.S. dollars)
discounted at 4% over 30-year period) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Options for Managing Lake Ontario and St. Lawrence River Water Levels and Flows
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FINAL REPORT