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Overview
Public Involvement
Phase 1 Report
Fact Sheets
Videos
GLAM Committee
Contact
Executive Summary
Chapter 1
1.0
Introduction
1.1
Purpose
1.2
Research leads to a Decision Support Tool
Chapter 2
2.0
Background on the system, the key players, and outflow regulation
2.1
Lake Ontario and the St. Lawrence River
2.2
The International Joint Commission
2.3
The International Lake Ontario-St. Lawrence River Board
2.4
The Great Lakes-St. Lawrence River Adaptive Management Committee
2.5
Public Advisory Group for phase 1 of the expedited review of Plan 2014
2.6
Plan 2014 outflow regulation
2.7
The uses and interests of Lake Ontario and the St. Lawrence River
2.7.1
Municipal and industrial water systems
2.7.2
Commercial navigation
2.7.3
Hydropower production
2.7.4
River and lake shoreline properties
2.7.5
St. Lawrence River and Lake Ontario ecosystems
2.7.6
Recreational boating and tourism
2.8
Indigenous Nations
Chapter 3
3.0
The Board and its deviation authority
3.1
The Board and extreme high water in 2017 and 2019-2020
3.1.1
High water in 2017
3.1.2
High water in 2019-2020
3.2
The Board and GLAM Committee collaborate
3.2.1
How the Board works
3.2.2
Factors that complicate deviation decisions
3.2.3
Information the Board wants and needs
3.3
The GLAM Committee examines Plan 2014’s limits for deviation possibilities
3.3.1
I Limit possibilities
3.3.2
L Limit possibilities
3.3.3
F Limit possibilities
Chapter 4
4.0
Data to inform the Board and the Decision Support Tool
4.1
Municipal and industrial water systems: Impacts to service
4.1.1
Surveys of Lake Ontario and St. Lawrence River municipal and industrial water use facilities
4.1.2
Assessment of water intake sensitivity on Lake St. Lawrence
4.1.3
Other activities and next steps
4.2
Commercial navigation: Financial and logistical impacts
4.2.1
Study estimates industry losses from navigation halts
4.2.2
Industry views on navigation halts
4.2.3
Other activities and next steps
4.3
Hydropower production: Winter operations
4.3.1
More aggressive I Limit deviation potential
4.3.2
Other activities and next steps
4.4
River and lake shoreline properties
4.4.1
Residents provide detailed impact reports
4.4.2
Municipalities’ impact data
4.4.3
Simulating building and agricultural land inundation
4.4.4
Other activities and next steps
4.5
Ecosystem response to deviation decisions
4.5.1
Winter operation impacts on Lake St. Lawrence biota
4.5.2
Other activities and next steps
4.6
Recreational boating: Data gathered from marinas
4.6.1
Marina and yacht club survey
4.6.2
Identifying potential tourism impact metrics
4.6.3
Other activities and next steps
4.7
Indigenous Nations
4.7.1
Reaching out to Indigenous Nations
4.7.2
Other activities and next steps
Chapter 5
5.0
GLAM Committee’s Decision Support Tool
5.1
Decision Support Tool water-supply forecasts
5.2
Metrics: Impact zones and broad-based views
5.3
Summarizing and visualizing the data in the Decision Support Tool
5.4
Tradeoffs displayed in the Decision Support Tool
5.5
Risk and uncertainty and the Decision Support Tool
Chapter 6
6.0
Input from Public Advisory Group
6.1
Public Advisory Group Work on the Decision Support Tool
6.2
Public Advisory Group’s assessment of the Phase 1 public engagement process
6.3
GLAM Committee appreciates Public Advisory Group’s work
Chapter 7
7.0
Findings and Recommendations from Phase 1 and transitioning to Phase 2: What comes next?
7.1
Summary of Key Findings
7.2
Recommendations from Phase 1
7.3
Transitioning to Phase 2 of the Expedited Review and a fulsome review of Plan 2014
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Executive Summary
Findings & Recommendations
Figures & Tables
Appendices
Figure 1
Fraction of the time that Plan 2014 rule curve or limits were applied versus the fraction of time that deviations were conducted in 2017 through 2020
Figure 2
Examples of shoreline impacts in 2017 and 2019.
Figure 3
Lake Ontario water levels 2, 2017-2020
Figure 4
Map of Lake Ontario and the St. Lawrence River
Figure 5
Water surface profile of the Great Lakes System
Figure 6
Roles and responsibilties of The International Lake Ontario- St. Lawrence River Board
Figure 7
Examples of municipal infrastructure flooding
Figure 8
Montréal is a major port on the St. Lawrence River
Figure 9
Moses-Saunders Power Dam on the St. Lawrence River, used to regulate outflows from Lake Ontario
Figure 10
Map of the St. Lawrence between Iroquois, Ontario and Lake St. Louis, Quebec including main facilities
Figure 11
Sandbanks Provincial Park, Prince Edward County, Ontario
Figure 12
Great egret hunting in a marsh of the St. Lawrence River
Figure 13
Federally-recognized Indigenous lands directly adjacent to the shoreline Lake Ontario or the St. Lawrence River
Figure 14
Flooding of homes along the shoreline within the Tyendinaga Mohawk Territory, May 2017
Figure 15
Total precipitation accumulation in April and May 2017 based on percent departure from the 2002-2016 mean.
Figure 16
Weekly net total supplies for the Lake Ontario basin in 2017, compared to record highs, lows and long-term average.
Figure 17
Lake Ontario outflows in 2017, showing when limits and Board deviations applied
Figure 18
Lake Ontario water levels in 2017, showing when limits and Board deviations applied
Figure 19
Ottawa River flow into the St. Lawrence River, 2017-2020
Figure 20
Residential and agricultural flooding along the shoreline of the St. Lawrence River near Maskinongé, Quebec
Figure 21
Lake Ontario outflows in 2019, showing when limits and Board deviations applied
Figure 22
Lake Ontario water levels in 2019, showing when limits and Board deviations applied
Figure 23
Plan 2014 Maximum L Limit showing actual flows in 2019 which exceeded the limit by 200 m3/s (7,100 cfs) as Lake Ontario levels dropped.
Figure 24
Lake Ontario outflows in 2020, showing when limits and Board deviations applied
Figure 25
Lake Ontario water levels in 2020, showing when limits and Board deviations applied
Figure 26
Actual (observed) versus pre-project (simulated) conditions from 2017 through 2020
Figure 27
Outflow impacts on water levels across the Lake Ontario – St. Lawrence River system
Figure 28
Vessel in the Seaway
Figure 29
Map of the St. Lawrence River, Lake Ontario to Montréal, along with hydro facilities
Figure 30
Facilities participating in LURA survey
Figure 31
St. Lawrence River ice cover, January 2018
Figure 32
2019 impacts by week
Figure 33
Illustration of flood inundation under different water levels
Figure 34
Illustration of transects generated on the Lake Ontario shoreline.
Figure 35
Transects incorporating homes and other buildings.
Figure 36
Simulated flooding of agricultural land surrounding Lake St. Pierre based on 2019 conditions
Figure 37
Low Lake St. Lawrence levels at Whalen Park Boat Launch, January 2020
Figure 38
Brockport (N.Y.) Yacht Club, April 2017
Figure 39
New York boating and tourism impacts by water level
Figure 40
illustration of forecast inputs (green) and outputs (blue and yellow) along with illustration of comparison forecast graphs for Lake Ontario levels (water supplies similar to 2005 highlighted in red)
Figure 41
locations with impact zones
Figure 42
Conceptual illustration of differences in community impact zones. Example impact zones for a number of different communities around Lake Ontario.
Figure 43
Graphical illustration comparing forecasts for a single water supply sequence using different deviation strategies relative to example impact zones.
Figure 44
Illustration of tradeoffs between impact zone communities based on the expected number of days at or exceeding the major water level category using the 80th percentile of forecast scenarios
Figure 45
Illustration of the number of buildings impacted upstream and downstream
Figure 46
Assessment of risk exposure. Risk = severity of impact times the probability of occurrence
Figure 47
Implications of uncertainty on repercussions and likelihood of outcomes
Table 1
List of six uses and interests as identified in ILOSLRSB, 2006 and IJC, 2014
Table 2
Lake St. Louis (Pointe Claire) levels corresponding to Lake Ontario levels for limiting lower St. Lawrence River flooding damages (F Limit).
Table 3
Indigenous Nations and Key Watersheds/Waterways
Table 4
Limits and area for further investigation
Table 5
Plan 2014 prescribed flows, 2017 to 2020.
Table 6
Actual flows, 2017 to 2020.
Table 7
Ranking of temporary Seaway closure scenarios, least to most costly
Table 8
Impacts related to commercial navigation scenarios
Table 9
Excerpt from output for Brighton, Ontario impact zone
Table 10
Differences between Phase 1 and Phase 2 of the expedited review effort
GLAM Committee membership
Credits and Acknowledgements
References
List of Contributors
Letter from the IJC to the GLAM Committee Initiating the Expedited Review of Plan 2014
List of Acronyms
Glossary of Terms
Letter from the IJC to the GLAM Committee Initiating the Expedited Review of Plan 2014
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