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One Hundred and Thirty-Second

Progress Report to the

International Joint Commission by the International Lake Ontario-St. Lawrence River Board

Covering the Period

1 March 2019 through 31 August 2019

25 September 2019

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Cover: From top left clockwise to bottom left: 1. Ogdensburg, NY 26 June, 2019: Bryce Carmichael, US Secretary

2. Flooding in Toronto, Ontario at Ontario Place, 02 June, 2019: Environment and Climate

Change Canada Staff 3. Flooding at Lake St. Louis, 02 June, 2019: David Fay, IJC

4. Flooding at Edgemere Drive, Greece, NY, 28 May, 2019: US Army Corps of Engineers,

Buffalo District

Executive Summary HYDROLOGICAL CONDITIONS, OUTFLOWS AND LEVELS Record inflows from Lake Erie and record high discharges from the Ottawa River into the lower St. Lawrence River during the spring resulted in another year of high water levels throughout the Lake Ontario – St. Lawrence River system, including the highest Lake Ontario water levels on record with the lake cresting at 75.92 m (249.08 ft). The resulting impacts of these unprecedented conditions affected all interest groups with the most noticeable impacts absorbed by the shoreline property owners throughout the Lake Ontario - St. Lawrence River system, despite every effort to alleviate the impacts of high water on all stakeholders. Water levels at the beginning of the reporting period on March 1st were above average, but forecasts were still indicating at the time that only under the very wettest of water supply sequences would water levels exceed the high criterion H14 thresholds, with no indication at that time that water levels would reach historic high levels. The end of February had been marked by widespread rain and very mild temperatures, causing significant snowmelt and runoff at the start of the reporting period in addition to continued high inflows from Lake Erie. Inflows from Lake Erie are an especially important factor in the determination of water levels as they typically contribute approximately 85% of the total water supplies into Lake Ontario. Water levels in March remained above average, but rose very little owing to dry conditions and high outflows, and levels were not significantly above March of 2018. With no indication of a significant risk of record high water levels to come, outflows were set according to Plan 2014 at some of the highest rates since the 1960s when regulation began. The high outflows resulted in extremely low water levels on Lake St. Lawrence, immediately upstream of Moses-Saunders Dam, which required careful adjustments over several weeks in winter and the first part of March to maintain a minimum level there of 71.80 m (235.6 ft) to protect municipal and domestic water intakes in this area. Outflows remained high through the end of March, and then followed the maximum L-limit starting in late-March with the opening of the St. Lawrence Seaway. This continued into April. Cool temperatures delayed snowmelt during the first half of the month, but by mid-April, as temperatures warmed, rainfall and snowmelt increased significantly in the Ottawa River basin, increasing flows into Lake St. Louis and the lower St. Lawrence River to record-high values. As high inflows from Lake Erie also continued, water levels began rising rapidly throughout the Lake Ontario – St. Lawrence River system. As has been the case during most springs since regulation began in 1960, Lake Ontario outflows were reduced as the Ottawa River increased in an attempt to balance high levels upstream and downstream. Plan 2014’s F limit is based in large part on previous Board operations, and it prescribes the maximum outflows that can be released from Lake Ontario while balancing the flood and erosion risk in the St. Lawrence River on and downstream of Lake St. Louis. As the water levels of Lake Ontario rise, the F Limit target water levels on Lake St. Louis also rise. The 2019 Ottawa River freshet broke the 2017 records, not only for maximum peak flows, but also for volume, lasting for three months before returning to average flows. Outflows from Lake Ontario were temporarily reduced, helping to mitigate – but not eliminate – the impacts in the St. Lawrence River downstream during the two peaks of this historic event. Meanwhile, upper Great Lakes water levels also rose in early spring and Lake Erie exceeded historic record highs at the start of May. Record inflows from Lake Erie, combined in part with the reduced outflows, resulted in Lake Ontario water levels rising rapidly from late April to late May. Throughout May and June, cool wet weather also contributed to high net basin water supplies. It is important to note that though the total amount of precipitation over the Great Lakes and St. Lawrence River basin was very high during the late winter and spring, there were some localized areas around Lake Ontario that did not receive as much wet weather as other areas in the system. Net total supplies to Lake Ontario in April were the 8th highest on record. Continued wet weather and record inflows from Lake Erie resulted in the month of May setting a record for

net total supplies of 11,150 m3/s (393,400 cfs), exceeding the previous record for May of 11,040 m3/s (289,900 cfs) set in May 2017. At the same time that record flows in the Ottawa River were occurring, the net total supply in April and May 2019 combined was the 2nd highest two-month total on record, behind only April and May 2017, further illustrating the exceptional nature of these events. During the week ending 10 May, the water levels of Lake Ontario exceeded the criterion H14 high level that applies at that time of year, authorizing the Board to deviate from regulation Plan 2014. As wet conditions continued throughout the month it became clear through the Board’s forecasts that the likelihood of reaching extremely high water levels on Lake Ontario was increasing. Outflows were increased according to the F-limit as Lake Ontario rose, increasing the water levels maintained in the lower St. Lawrence River at Lake St. Louis. Considering the continuing near-record inflows from the Ottawa River, which were contributing to severe flood damages along the lower St. Lawrence River from Lake St. Louis to Lake St. Pierre, the Board decided to continue following the F Limit at that time in May in an attempt to balance these impacts with the damages and impacts that were also increasing on Lake Ontario and the upper St. Lawrence River. This decision came after significant deliberation and consideration of language in criterion H14 to provide all possible relief to riparians upstream and downstream (of Moses Saunders dam).

Late in May, the Ottawa River flows began to decline more rapidly. This allowed immediate increases of Lake Ontario outflow, despite Lake St. Louis still being slightly above the uppermost F Limit and still f looding. Within a few days, by 6 June, outflows had reached the L Limits of Plan 2014, the maximum outflow rate deemed safe for commercial navigation. Also on 6 June, water levels on Lake Ontario peaked at 75.92 m (249.08 ft), and the Board decided to deviate from Plan 2014 and after careful consideration of the range and degree of risks for all stakeholders, increased the outflow above the maximum L-limit to 10,400 m3/s (367,300 cfs) on 13 June. This was equivalent to the record maximum sustained outflow first released in 2017. These outflows caused the Seaway to put in place mitigation measures such as restricted passing zones, tug assistance, and slower transit speeds to ensure safe transit of vessels under the high outflow conditions. These mitigation measures were implemented at significant cost to the Seaway Corporations. This record-high sustained outflow of 10,400 m3/s (367,300 cfs) was maintained for 69 days until 21 August. This was by far the longest period of sustained record outflows ever maintained through St. Lawrence River. With the available capacity of Moses-Saunders Dam exceeded through much of this period, the excess flow was released through Long Sault Dam. Thereafter, major deviations continued as the Board decided to continue to release outflows above Plan 2014, increasing outflow to 200 m3/s (7100 cfs) higher than maximum L-limit for safe navigation in order to further accelerate the decline in Lake Ontario levels and lower the lake as quickly as possible. The Seaway Corporations maintained the mitigation measures they had imposed in the spring to ensure safe navigation was able to continue despite the continuance of record-high outflows. Deviations and outflows above Plan 2014 continued through the remainder of the reporting period.

BOARD ACTIVITIES The Board met in person once in early March, along with International Joint Commission (IJC) staff, associated subcommittees, and advisory groups to assess conditions and to review regulatory operations, outreach efforts, feedback and adaptive management initiatives. Discussion of current conditions recognized that Lake Erie levels were higher than average and there was above-average snowpack in the Ottawa River basin, but the early March forecast risk of high water levels was not significantly different than what was observed during many previous

years when there were no high water events. Once it became clear that unprecedented high water supplies in the entire Lake Ontario – St. Lawrence River basin, including the Ottawa River valley, were occurring the Board began meeting regularly by teleconference to address their responsibilities for setting the outflow of Lake Ontario. The Board met 17 times during the reporting period to proactively set outflows that would provide all possible relief to riparians upstream and downstream of the dam.

The regulation representatives provided the Board with daily information on conditions in the system during the peak of the event, including reviews of hydrologic conditions and forecasts. Provision of this information continued through summer as often as necessary. The Operations Advisory Group (OAG) continued its weekly teleconference to apprise the regulation representatives of operational requirements and constraints, and responded to Board queries during the high water crisis. Experts from different interest groups were consulted to provide input on the impacts of proposed regulation strategies on all stakeholder groups. Additionally, the Board constantly coordinated information on regulatory strategies with the Ottawa River Regulation Planning Board.

COMMUNICATION ACTIVITIES During the reporting period, the Communications Committee, individual Board members, the secretaries and the regulation representatives were actively engaged in outreach, information exchange and liaison with stakeholders throughout the Lake Ontario – St. Lawrence River system.

The Board made a concerted effort to enhance public communication through its website and Facebook pages while addressing the anguish of many who suffered damages from high water in 2019. Since the beginning of March, 16 media releases were published and posted on its website. Many additional posts on the Board’s Facebook page addressed issues of concerns to those on the page. Board members and staff met with individuals and agencies around the Lake Ontario – St. Lawrence River basin. The Canadian Regulation Representative provided regular water condition updates with provincial water managers, conservation authorities and municipalities in Ontario. The US Regulation Representative participated in regular teleconferences addressing the emergency high water levels in New York State.

TABLE OF CONTENTS

1. Hydrological Conditions ......................................................................................................................................... 3 1.1. Lake Ontario Basin - Net Basin Supply............................................................................................................... 4 1.2. Precipitation.............................................................................................................................................................. 4 1.3. Supply from Lake Erie ............................................................................................................................................ 4 1.4. Lake Ontario – Net Total Supply .......................................................................................................................... 4 1.5. Ottawa River Basin ................................................................................................................................................. 4 2. Regulatory Operations ........................................................................................................................................... 5 2.1. Regulation Overview............................................................................................................................................... 5 2.2. Deviations from Regulation Plan 2014 ............................................................................................................... 6 2.3. Water Levels throughout the System .................................................................................................................. 6 2.4. Iroquois Dam Operations....................................................................................................................................... 8 2.5. Long Sault Dam Operations.................................................................................................................................. 8 2.6. Raisin River Diversion ............................................................................................................................................ 8 2.7. St. Lawrence Seaway Report ............................................................................................................................... 8 2.8. Hydropower Peaking and Ponding ...................................................................................................................... 8 3. Board Activities........................................................................................................................................................ 9 3.1. Board Meetings & Conference Calls ................................................................................................................... 9 3.2. Board and Committee Membership Changes.................................................................................................... 9 3.3. Communications, Outreach and Engagement .................................................................................................. 8 3.4. Gauging Committee ..............................................................................................................................................10 4. Adaptive Management Committee ....................................................................................................................10

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LIST OF TABLES Table 1. Provisional Monthly Mean Supplies to Lake Ontario Table 2. Provisional Precipitation over the Great Lakes and Lake Ontario Basins Table 3a. Summary of Weekly Flows, Operational Adjustments and Deviations Table 3b. Summary of Flow Changes Table 4. Lake Ontario Recorded and Preproject Levels and Outflows Table 5. Attendance at Meetings

LIST OF FIGURES Figure 1. Monthly Net Total Supplies to Lake Ontario Figure 2. Daily Ottawa River Flow at Carillon Figure 3. Lake Ontario Daily Outflows Figure 4. Daily Lake Ontario Water Levels Figure 5. Lake Ontario Actual, Preproject & Plan 2014 Levels Figure 6. Daily Lake St. Lawrence Levels at Long Sault Dam Figure 7. Daily Lake St. Louis Levels at Pointe-Claire Figure 8. Daily Port of Montreal Levels at Jetty # 1 Figure 9. Daily Lake St. Peter Levels at Sorel

Appendix A: Communications Committee Summary of Activities Appendix B: Communications Committee Membership Appendix C: Facebook Summary Report Appendix D: Glossary, Abbreviations, and Background Information on ILO-SLRB website

Appendix D, available on the Publications page of the Board’s website, provides the background information that had been included in the main body of these reports previously, allowing this report to focus on the issues and conditions of the reporting period.

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1. Hydrological Conditions 1 2 As noted in the Executive Summary, 2019 brought unprecedented waters supplies to the Lake 3 Ontario - St. Lawrence River system, including the Ottawa River basin. Resulting water levels 4 throughout the system reached record highs and caused a multitude of severe high-water 5 impacts. All possible outflow regulation strategies were explored that could potentially provide 6 relief to those impacted. However, these efforts continued to be challenging, owing to the 7 physical limitations of the Lake Ontario – St. Lawrence system, the wide range of interests 8 impacted by water level f luctuations upstream and downstream, and the limited influence of 9 outflow regulation and its ability to alleviate high water conditions when faced with the extreme 10 events observed in 2019. 11 12 A stable ice cover was maintained through winter, and began slowly melting without incident in 13 late-February and early March, allowing outflows to be increased to well-above average values 14 that continued during March and into April. The high outflows, combined with relatively cool, 15 dry weather resulted in a below-average rise in Lake Ontario levels in March. 16 17 Cool temperatures continued in April and delayed snowmelt during the first half of the month, but by 18 mid-April, as temperatures warmed, rainfall and snowmelt increased significantly in the Ottawa River 19 basin, increasing flows into Lake St. Louis and the lower St. Lawrence River to record-high values. 20 The Ottawa River peak more than doubled its long-term average (1963-present), and the high 21 f lows from the Ottawa River into the lower St. Lawrence River lasted for about three months. 22

23 Wet spring weather extended to the Great Lakes basin as well. Each of the upper Great Lakes 24 exceeded record-high levels in spring, with the exception of Lake Michigan-Huron, which was 25 slightly below record-highs throughout. On Lake Erie, this resulted in record outflows through 26 the Niagara River and into Lake Ontario by the start of May. Conditions around the Lake 27 Ontario basin itself were also very wet in April and especially May, and combined with record-28 inflows from Lake Erie, April and May together recorded the 2nd highest two-month net total 29 supply on record, just shy of the previous record set in April and May 2017. 30 31 Water levels on Lake Ontario rose quickly in late-April and May in response to the high inflows and in 32 combination with the outflow reductions in mid-April and early-May as the Ottawa River rose, 33 which helped to mitigate, but not eliminate flooding and other high water damages 34 downstream. Similarly, on Lake St. Pierre, in the lower St. Lawrence River, water levels in late-April 35 exceeded the highs seen in 2017. Outflows from Lake Ontario were increased as the Ottawa River 36 subsided, increasing the level maintained at Lake St. Louis to similar values seen in 2017. Flooding 37 and high water damages were reported both upstream and downstream throughout this period. 38 39 Cool, wet weather persisted through June and into July, which was close to average. August 40 was hot with below-average rainfall. Inflows from the upper Great Lakes remained above 41 normal throughout the reporting period. Inflows from Lake Erie exceeded record highs in May 42 through August. Thus, net total inflows to Lake Ontario remained well above normal, even 43 during the drier late-summer conditions in its local drainage basin. 44 45 Lower St. Lawrence River levels began to decline in June as the Ottawa River subsided and 46 despite record-outflows from Lake Ontario. Lake Ontario water levels persisted at seasonal record 47 high levels for several weeks, largely due to record inflows from Lake Erie and despite the record-high 48 outflows, and this continued until mid-August when they fell below the record levels last seen in 49 August 1947. 50

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51 1.1 Lake Ontario Basin - Net Basin Supply 52

53 The local net basin supplies (NBS) to Lake Ontario (see Appendix C for definition) were slightly 54 below average in March and August, and above from April through July. Net basin supply was 55 the fifth highest on record (1900-2018) for the month of May. Monthly NBS values for the period 56 of March through August overall was the 10th highest on record. Monthly data and the averages 57 for the six-month period are provided in Table 1. 58

59 1.2. Precipitation 60

61 Monthly precipitation amounts for the Lake Ontario and Great Lakes basins, and the average for 62 the six-month period are provided in Table 2. Precipitation over the Lake Ontario basin was 63 below average in March, above to well-above average in April, May and June, then below average 64 again in July and August. The monthly average precipitation from March through August over the 65 Lake Ontario basin was 84 mm (3.31 in), which was above average and has been exceeded 28 66 percent of the time. The monthly average precipitation from March through August for the entire 67 Great Lakes basin was 74 mm (2.91 in), which was near average, having been exceeded 48 68 percent of the time. Similar to Lake Ontario, the wettest months in the upper Great Lakes basin 69 occurred in April and May. 70

71 1.3. Supply from Lake Erie 72

73 Reflecting the high water levels in the upper Great Lakes, the inflows to Lake Ontario from Lake 74 Erie remained well above-average throughout the reporting period – and record high from May 75 through August - as shown in Table 1. The six-month average outflow of 7,740 m3/s is 76 provisionally the highest March through August average outflow since Lake Erie outflow records 77 began in 1900. 78

79 1.4. Lake Ontario – Net Total Supply 80

81 The monthly net total supplies (NTS) to Lake Ontario (see Appendix C for definition) are 82 provided in Table 1 and shown graphically in Figure 1. The monthly mean net total supplies 83 remained above average throughout the reporting period, and surpassed the record for the 84 month of May that was previously set in May 2017. May 2019 is also the 2nd highest net total 85 supply recorded in any month of the year (1900-2018), being exceeded only in April 1993. Net 86 total supplies were the 8th highest ever recorded in the month of April, and 2nd highest in each 87 of the months of June, July and August. Overall, the net total supply was 128 percent of 88 average during this reporting period, and is provisionally the highest March through August 89 average NTS since reliable record keeping began in 1900. Figure 1 shows the long-term 90 average monthly net total supplies for the period 1900 to 2018 and the supplies so far for 2019. 91 Also shown, for comparison purposes, are the monthly NTS for 2017 and 2018. The horizontal 92 bars above and below the curves on the graph are the long-term monthly NTS maxima and 93 minima. 94

95 1.5.Ottawa River Basin 96

97 Figure 2 shows the daily Ottawa River flows. Flows were about average in March. Following 98 cool temperatures and little rainfall near the beginning of April, Ottawa River flows rose quickly 99 as heavy precipitation, warmer temperatures and snowmelt increased starting in mid-April. The 100

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f lows of the Ottawa River in 2019 peaked 30 April at 9,217 m3/s (325,500 ft3/s) more than two 101 and a half times the average (1963-2018) peak of 3,547 m3/s (125,300 ft3/s) and above the 102 previous daily record-high of May 2017. Additional rainfall in May resulted in a second peak on 103 15 May, still near record highs and more than twice the average flow for this time of year. Ottawa 104 River flows generally declined slowly thereafter, falling below average values by late-July, where 105 they remained throughout the rest of the reporting period. 106

107 2. Regulatory Operations 108

109 2.1. Regulation Overview 110

111 In order to be responsive to conditions and the needs of all interests in the Lake Ontario – St. 112 Lawrence River system, the Board continuously assessed conditions throughout the reporting 113 period through numerous email exchanges along with the aid of regular monthly and weekly 114 reports from the regulation representatives. From late-April until 26 July the Board discussed 115 outflow strategies to address the extremely wet conditions through weekly teleconferences and 116 bi-weekly through August. The Board held 17 teleconferences during the reporting period. 117

118 Figure 3 shows the actual daily Lake Ontario outflows for the reporting period in comparison to 119 the long-term average, preproject and weekly plan-specified outflows. Tables 3a and 3b show 120 the flow changes including operational adjustments and deviations that occurred during the last 121 half year. Most deviations require that subsequent offsetting outflows return the level of Lake 122 Ontario to what it would have been if outflows had followed plan-prescribed flows all along. 123 However, operational adjustments are not required to be paid back by subsequent offsetting 124 outflows. 125

126 During the first week in March, outflows were set according to Plan 2014’s I limit, which 127 prescribes the maximum outflows that can be released from Lake Ontario, while ensuring stable 128 ice conditions and maintaining minimum critical water levels on Lake St. Lawrence. The L limit 129 prescribes the maximum outflows that can be released from Lake Ontario, while maintaining 130 safe navigation conditions in the upper St. Lawrence River. The L-limit was applied from when the 131 Seaway opened on 26 March through the week ending 12 April. The March monthly-mean outflow 132 was 8,690 m3/s, the sixth highest since records began in 1900, and just 800 m3/s less than the 133 record in March 1998. 134

135 Mild temperatures, wet conditions and rapid snowmelt in mid-April resulted in a rapid rise in the 136 Ottawa River. Starting late-April, Plan 2014’s F limit prescribed the maximum outflows that could 137 be released from Lake Ontario, which was starting to rise rapidly, while also balancing rising 138 levels and similar flood and erosion risks on the lower St. Lawrence River at and below Lake St. 139 Louis as well. The Ottawa River peaked at record-highs in late-April, even above the record-140 breaking volumes during the spring of 2017. During the week ending 10 May, at around the same 141 time as a second peak of the Ottawa River occurred, the water levels of Lake Ontario exceeded the 142 criterion H14 upper trigger levels, authorizing the Board to deviate from Plan 2014. Considering the 143 Ottawa River conditions and the impacts downstream on the St. Lawrence River, the Board 144 decided to continue to maximize Lake Ontario outflows in accordance with the F Limit. 145 146 In late-May, the Ottawa River flows were declining, but Lake St. Louis was still near and slightly 147 above the uppermost F Limit and still f looding. Since Lake Ontario water levels were still rising 148 (and above the criterion H14 high level for early June), the Board authorized an increase in 149 outflows to maintain the same high level at Lake St. Louis while Ottawa River flows decreased. 150

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By 6 June, outflows had reached the L limits of Plan 2014, the maximum outflow rate deemed 151 safe for navigation. Since the Board still had the authority to deviate from Plan 2014, outflows 152 were slowly increased, eventually rising above the maximum L-limit value on 13 June, to a flow 153 of 10,400 m3/s (367,300 ft3/s), the record maximum sustained outflow first released during the 154 high water event in 2017. This outflow rate increased river currents to 1.4 times normal values 155 in some areas of the channel and established strong cross-currents at a number of critical 156 points in the river, which presented additional challenges for the safe navigation of commercial 157 navigation. With mitigation measures and transit restrictions in place, the Seaway remained 158 open even at these extreme currents. 159

160 161

2.2. Deviations from Regulation Plan 2014 162 163 Figure 3 shows daily outflows compared to weekly plan-specified outflows from Lake Ontario. 164

165 In May, major deviations from Plan 2014 started to remove water from Lake Ontario despite high 166 water levels on Lake St. Louis, which was flooding and above the upper F Limit. From 13 June 167 to 20 August inclusive, for 69 days and 15 more than in 2017 - outflows were set at a flow of 168 10,400 m3/s (367,300 ft3/s) and 200 m3/s (7100 cfs) higher than the maximum L Limits of Plan 169 2014. This unprecedented, sustained high outflow rate had only ever been exceeded for short, 170 24 hour intervals at a time in 1993 – at that time, a slightly lesser average flow of 10,190 m3/s 171 (359,900 cfs) was achieved during the navigation season using off-and-on flow patterning, with 172 24-hour flow increases from 9900 to 10900 m3/s (349,600 to 384,930 cfs) occurring 173 approximately twice per week over a period of 23 days. In 1993, this outflow patterning had 174 suspended shipping during the days of higher outflows and caused additional erosion in the St. 175 Lawrence River, while lowering the level of Lake Ontario by less than the sustained outflow of 176 10,400 m3/s (367,300 ft3/s) passed in 2019. Under the high water conditions of 1998, the Board 177 also did not employ patterning owing to significant adverse effects along the river reported following 178 the 1993 period. 179

180 On 21 August, Lake Ontario levels had declined below 75.50 m (247.7 ft), more than 0.5 m 181 (1.5 feet) below the 2019 peak, and velocities in the St. Lawrence River continued to 182 increase. Outflows were reduced slightly to 10,110 m3/s (357,000 ft3/s), still 200 m3/s 183 (7,100 ft3/s) more than the maximum Plan 2014 L Limit. Outflows continued to be reduced 184 gradually as Lake Ontario continued to decline, but were maintained at 200 m3/s (7,100 185 ft3/s) above the L Limit for the rest of the reporting period. These outflow deviations were 186 an attempt by the Board to continue lowering the water level of Lake Ontario as quickly as 187 possible, while balancing all interests of the entire Lake Ontario – St. Lawrence River 188 system. 189

190 2.3. Water Levels throughout the System 191

192 Figure 4 shows the levels of Lake Ontario, which are primarily affected by water supplies to the 193 lake, and to a lesser degree by outflows. As described in Sections 2.1 and 2.2, outflows generally 194 followed Plan 2014 except during the major deviations from June through August. For 195 comparison purposes, the daily levels of 2017, 2018 and 2019 through August are shown. Lake 196 Ontario levels remained above average and at about the same level as in 2017 and 2018 for the 197 month of March. They then rose rapidly from mid-April to late-May, peaking at 75.92 m (249.08 ft) 198 on 6 June, 4 cm (1.6 in) higher than the previous record-high peak of late-May in 2017. Thereafter, 199 the lake levels remained relatively stable, within about a centimeter (less than an inch) of the 200

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record-peak, for about twenty more days until 23 June owing to the record-inflows from Lake Erie 201 and continuing high basin supplies, and despite the record high outflows, released during this 202 period. Levels of Lake Ontario declined at an increasing rate through June and August, and at the 203 end of the reporting period, the level was at 75.37 m (247.28 ft), still 55 cm (21.7 in) above 204 average, but also 55 cm (21.7 in) below the 2019 peak and 14 cm (5.5 in) lower than the record-205 high level set at the end of August 1947. 206 207 As a means of determining the impact of regulation activities on levels and outflows, the Board 208 provides a comparison of Lake Ontario’s actual monthly levels and outflows to those that would 209 have occurred under preproject conditions (i.e. the levels and outflows that would have occurred 210 had regulation not been undertaken and the Moses Saunders Dam was not constructed). A 211 summary of this comparison for the reporting period is given in Table 4. This summary shows 212 that the actual level of Lake Ontario ranged from 32 cm (1.0 ft) to 72 cm (2.4 ft) lower than it 213 would have been compared to preproject conditions. A comparison of the daily levels to long-214 term average, weekly computed Plan 2014 levels, and the levels that would have occurred 215 under preproject conditions is also shown in Figure 5. 216

217 The water levels at Long Sault Dam on Lake St. Lawrence (Figure 6) were well below average 218 and at minimum winter levels until late-March, when the water level rose as the ice cover 219 receded. Lake St. Lawrence levels fluctuated near average in April through July. In August, 220 Lake St. Lawrence levels declined in response to the high outflows and declining levels of Lake 221 Ontario. Though levels remained very low through the end of the reporting period, levels stayed 222 above record-low values. Local residents and boaters contacted the Board with their concerns 223 about such low levels for the third straight year, coinciding with high levels elsewhere and 224 following the implementation of Plan 2014. On 31 August, the water level was 72.89 m (239.14 225 ft), 40 cm (15.7 in) below the long-term average, and just 16 cm (6.3 in) above the record low 226 set for late August in 1987. 227

228 Daily water levels at Summerstown on Lake St. Francis were generally below or at average from 229 March through May. Thereafter, Lake St. Francis levels were above average. The record-high 230 outflows from June to August kept the water levels here close to maximum values, thus daily 231 mean levels were at or above the Seaway Low Alert level throughout the navigation season (so 232 commercial vessel traffic was not impeded by low levels in this section of the river). 233

234 The daily water levels at Pointe Claire on Lake St. Louis remained well above average over the 235 past six months, as shown in Figure 7. Levels rose sharply in mid-April with the record-high 236 freshet flows from the Ottawa River. Outflows from Lake Ontario were adjusted according to the 237 Plan 2014 F-limit from April until early June. June’s monthly mean Lake St. Louis level was a 238 new record high. 239

240 The daily levels at the Port of Montreal are shown in Figure 8. Montreal levels were above 241 average in March, close to the levels of the preceding two years until mid- April, when they 242 quickly also spiked to near record-high values, but below the highest levels of 2017. After 243 peaking in early May, levels generally fell thereafter, staying close to the levels of 2017. Water 244 levels remained well above chart datum throughout the reporting period. Chart datum is 245 selected so that water levels seldom fall below it and only rarely is there less depth available 246 than what charts depict. 247

248 The daily levels of Lake St. Peter at Sorel are shown in Figure 9. Levels hovered near average 249 in March. Levels then rose rapidly in mid-April, reaching record high values by month’s end, 250

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before slowly subsiding throughout the rest of the summer. Water levels remained well above 251 chart datum throughout the reporting period. May and June monthly mean values were new 252 record highs. 253

254 2.4. Iroquois Dam Operations 255

256 Gates at Iroquois Dam were lowered by the Power Entities starting on 18 April and adjusted 257 frequently over the next several weeks in order to maintain high Lake St. Lawrence levels 258 below flood levels during the Ottawa River freshet and period of reduced outflows from Moses-259 Saunders Dam. The gates at Iroquois Dam were gradually raised as outflows again increased, 260 but due to safety concerns and Lake Ontario outflows surpassing 9500 m3/s (335,500 cfs), the 261 recreational navigation gates at Iroquois Dam remained closed to recreational boaters. These 262 very high outflows were sustained through the rest of the reporting period causing these gates 263 to remain closed through 31 August. 264 265

2.5. Long Sault Dam Operations 266 267

The Power Entities opened a varying number of gates at Long Sault Dam, at differing times 268 throughout the reporting period, to spill the amount of the total Lake Ontario outflow that 269 exceeded the capacity of the Moses-Saunders Dam. Spills occurred on 7-8 March, 27-28 270 March, 4-5 April, 21 May, and 25-30 May. Then, beginning 1 June and continuing through the end 271 of the reporting period, various amounts of spill occurred daily as the high outflows from Lake 272 Ontario exceeded the available capacity of Moses-Saunders Dam. The total amount of water 273 spilled (lost to electrical power generation) reached a maximum daily average value of 274 2,590 m3/s (91,500 ft3/s) on 22 August. 275

276 2.6.Raisin River Diversion 277

278 The Raisin River Diversion was not opened during the reporting period. 279

280 2.7.St. Lawrence Seaway Report 281

282 The St. Lawrence Seaway opened 27 March. The first vessel to transit the Seaway’s 283 Montreal/Lake Ontario section was the upbound M/V Federal Kumano on 27 March. The 284 Seaway corporations implemented mitigation measures to ensure safe navigation during the 285 record outflows and major deviations conducted by the Board during the summer. 286

287 2.8.Hydropower Peaking and Ponding 288

289 By letter dated 13 October 1983, the International Joint Commission (IJC) authorized Ontario 290 Power Generation (OPG) and New York Power Authority (NYPA) to continue to carry out 291 peaking and ponding operations at the St. Lawrence Project. The conditions and directives 292 governing peaking and ponding operations are currently specified in Addendum No. 3 to the 293 Operational Guides for Regulation Plan 1958-D. On 4 November 2016, the IJC renewed the 294 approval for a 5-year period, dated 1 December 2016 to November 30, 2021. 295

296 No ponding operations were conducted from 1 March 2019 to 31 August 2019. Peaking 297 operations were permitted from 15 April to 21 May but were not conducted during this period. 298 These operations were also suspended during other higher flow periods due to the conditions 299 downstream. 300

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301 3. Board Activities 302

303 The Board continued to direct the outflow from the hydropower project in the international reach of 304 the St. Lawrence River. The Board, primarily through the offices of the regulation representatives, 305 monitored conditions throughout the Lake Ontario-St. Lawrence River system. In response to the 306 unprecedented high water supplies in the entire Lake Ontario – St. Lawrence River system, 307 including the Ottawa River basin, the Board also met 17 times by teleconference to address 308 their responsibilities for setting the outflow of Lake Ontario. The regulation representatives 309 provided the Board with weekly and at critical times daily water level, forecast, and hydrologic 310 conditions updates, weekly regulation data and monthly reviews of the hydrological conditions. 311 From late-April through August, the Board frequently discussed outflow strategies to address 312 the extremely wet conditions through weekly teleconferences and bi-weekly or weekly through 313 August. The Board’s Operations Advisory Group (OAG) continued to hold weekly teleconferences 314 to review conditions and advise the regulation representatives on weekly operational requirements 315 and constraints. The OAG also answered queries on regulation strategies from the Board. The 316 Board continued to work with the IJC, through the Communications Committee, to seek 317 opportunities to enhance communications, outreach, and engagement with its stakeholders and 318 the public. The Committee on River Gauging continued to monitor the Power Entities’ program for 319 operation and maintenance of the gauging system required for Board operations, hold 320 teleconferences as necessary, report to the Board four times annually, and prepare an annual 321 report. 322 323

3.1. Board Meetings & Conference Calls 324 325 The Board held a face-to-face meeting on 6 March in Syracuse, NY along with IJC staff, 326 associated subcommittees, and advisory groups to conduct business and assess conditions 327 during the reporting period. Table 5 provides a list of Board members in attendance at this in-328 person meeting. 329 330 From late April through the end of August the Board discussed outflow strategies to address 331 the extremely wet conditions through regular teleconferences. 332

333 3.2. Board and Committee Membership Changes 334

335 The IJC added an additional US Board member and plans to add another Canadian Member 336 in the near future. These two new members have been selected from local municipalities 337 within the Lake Ontario – St. Lawrence River system and have a multitude of experience with 338 the impacts from high water events on shoreline residents and property owners. Mr. Bill 339 Reilich was appointed on 28 August 2019 for a three year term. Mr. Reilich has served as the 340 Supervisor of the Town of Greece, NY since 1 January, 2014. 341

342 3.3. Communications, Outreach and Engagement 343

344 During the reporting period, the Communications Committee, individual Board members, the 345 secretaries and the regulation representatives were actively engaged in outreach, information 346 exchange and liaison with stakeholders throughout the Lake Ontario – St. Lawrence River 347 system and participated in various stakeholder and public meetings. Full details on recent 348 communications activities are in Appendix A and the members of the joint Board-IJC 349 Communications Committee are listed in Appendix B. 350

10

351 Board members and staff responded to a number of telephone and email inquiries from local 352 government officials, interested stakeholders and members of the general public concerning 353 water level conditions and Board strategies, and conducted numerous interviews with the media. 354 Weekly and monthly updates on the Board’s website continue to be posted in both French and 355 English, and Board staff frequently respond to public questions and comments. The English and 356 French Facebook pages currently have over 4,898 and 495 “likes” respectively. The Board’s 357 Facebook posts have had a total reach of 690,000 during the reporting period. 358

359 The Board and Commission responded to multiple concerns and complaints from mid-May 360 onward during the high water on Lake Ontario and the Upper St. Lawrence River, and this 361 proved to be the most challenging outreach effort since 2017’s high-water period. 362

363 The Board continued to operate and maintain its website (https://www.ijc.org/en/loslrb). The 364 website currently includes: 365

• Tabular and interactive graphical updates on daily water levels and outflows, weekly 366 water level forecasts, frequently updated information on outflow changes and water 367 supply conditions; 368

• General information about the Board, its activities and its structure; 369 • Current and archived media releases; 370 • Frequently Asked Questions and responses; 371 • Semi-annual progress reports, meeting minutes, and other background 372

publications; 373 • Animated “Learning Modules”; 374 • Video Gallery of past public teleconferences; 375 • Photo Gallery displaying content from the Board’s Flickr page; 376 • Information “wiki” piece on Lake St. Lawrence. 377

378 3.4. Gauging Committee 379

380 The St. Lawrence Committee on River Gauging (Gauging Committee) is granted authority by the 381 Board to ensure the accuracy of flow estimates and water level measurements in the 382 international section of the St. Lawrence River. The Gauging Committee inspects the 383 computational methods employed at each of the eight outflow structures and monitors the 384 operation and maintenance of the water level gauges owned and operated by the Power Entities. 385 The committee conducts an annual f ield inspection of 16 of the water level gauges used 386 by the Board to monitor river conditions and performs monthly audits of the water level and 387 outflow data collected and archived by the Power Entities. The findings and results of these 388 activities are documented in an annual report to the Board. 389

390 The 81st (2017) Gauging Committee report is being finalized, and the 82nd (2018) report is currently 391 being prepared. The 2019 annual water level gauge field inspection took place 12-15 August 392 2019. 393

394 4. Adaptive Management Committee 395

396 The Great Lakes - St. Lawrence River Adaptive Management (GLAM) Committee of technical 397 experts, established by the IJC to consider adaptive management methods under the authority 398 of the Boards, as part of an on-going evaluation of regulation plans, continued to work with the 399 Board to implement the science-based recommendations of past studies and develop new 400

11

ones. The Board seeks to evaluate regulation plan performance over time with regard to a 401 broad range of environmental and economic indicators. The committee has been very active 402 and prepared study plans to investigate improvements to outflow strategies from Lake Ontario. 403 The accelerated evaluation of Plan 2014 is expected to investigate trigger levels, the 404 economic impacts of shipping, the minimum level for Lake St. Lawrence and varying the F 405 Limits, as well as improving the assessment of economic losses due to high water throughout 406 the Lake Ontario – St. Lawrence River system. For more information on GLAM’s activities, 407 refer to the progress reports on the GLAM Committee’s website. 408

10

Respectfully submitted,

MEMBERS FOR CANADA MEMBERS FOR THE UNITED STATES

S. DURRETT, Alt. CHAIR

D. KUEHN

W. REILICH

12

Table 1 Provisional Monthly Mean Supplies to Lake Ontario

Month Inflow from Lake Erie Local Net Basin Supplies Total Supplies

m3/s tcfs Exceed.

Prob.(1) % of LTA

(1) m3/s tcfs Exceed.

Prob. (1) m3/s tcfs Exceed. Prob. (1)

% of LTA

(1)

Mar 19 7060 249 5 122 1760 62 62 8820 311 19 113

Apr 19 7320 259 6 121 3180 112 24 10500 371 6 122

May 19 8040 284 <1 128 3110 110 4 11150 394 <1 140

Jun 19 8220 290 <1 130 1930 68 8 10150 358 <1 136

Jul 19 8000 283 <1 129 1020 36 18 9020 319 <1 131

Aug 19 7820 276 <1 128 150 5 58 7970 281 1 126

6-month Average 7740 273 1 126 1860 66 6 9600 339 <1 128

(1) Based on period of record 1900-2018

Table 2

Provisional Precipitation over the Great Lakes and Lake Ontario Basins

Month Great Lakes Basin Lake Ontario Basin

mm (inches) % of LTA(1) Exceed. Prob.(1)

mm (inches) % of LTA(1) Exceed. Prob.(1)

Mar 19 45 (1.77) 82 71 53 (2.09) 79 74

Apr 19 85 (3.35) 131 15 92 (3.62) 124 22

May 19 94 (3.70) 122 20 114 (4.49) 144 14

Jun 19 90 (3.54) 110 37 99 (3.90) 122 27

Jul 19 66 (2.60) 83 78 69 (2.72) 86 66

Aug 19 61 (2.40) 76 84 75 (2.95) 94 56

6-month Average 74 (2.91) 101 48 84 (3.31) 109 28

(1) Based on period of record 1900-2016

13

14

Table 3a: SUMMARY OF WEEKLY OUTFLOWS, OPERATIONAL ADJUSTMENTS AND DEVIATIONS

Week Ending 2019

Adj. RC Flow Plan Flow App. Rule/ Limit

Actual Flow Op. Adjustments

Deviations

Details Weekly Accumulated Cumulative

effect on L. Ontario

Type m3/s tcfs m3/s tcfs m3/s tcfs m3/s tcfs m3/s tcfs m3/s

-wks tcfs- wks cm in.

1-Mar 8900 314 8580 303 I 8580 303 -320 -11.3 OAs for max I-limit (maintain L. St. Lawrence at 71.80 m)

8-Mar 8840 312 8700 307 I 8700 307 -140 -4.9 OAs for max I-limit (maintain L. St. Lawrence at 71.80 m)

15-Mar 8670 306 8670 306 RC 8670 306 0 0 Plan (Rule Curve) 22-Mar 8680 307 8680 307 RC 8680 307 0 0 Plan (Rule Curve)

29-Mar 8820 311 8710 308 RC/L 8710 308 -110 -3.9 Plan (Rule Curve), then decrease to Plan (maximum L-limit) at opening of Seaway navigation season on 26-Mar

5-Apr 8800 311 8620 304 L 8630 305 -170 -6 10 0.4 10 0.4 0.0 0.0 Unintentional Plan (maximum L-limit) 12-Apr 8960 316 8680 307 L 8680 307 -280 -9.9 0 0 10 0.4 0.0 0.0 -- Plan (maximum L-limit)

19-Apr 9040 319 7900 279 F 7890 279 -1150 -40.6 -10 -0.4 0 0 0.0 0.0 Minor (Op) Plan (maximum L-limit), and OAs for max. F-limit (maintain L. St. Louis at 22.10 m while L. Ont. <75.30 m)

26-Apr 9140 323 5880 208 F 5880 208 -3260 -115

OAs for max. F-limit (maintain L. St. Louis at 22.10 m while L. Ont. <75.30 m, maintain L. St. Louis at 22.20 m while L. Ont. >= 75.30 m & < 75.37 m)

3-May 9440 333 5980 211 F 5980 211 -3460 -122 OAs for max. F-limit (maintain L. St. Louis at 22.33 m while L. Ont. >= 75.37 m & < 75.50 m)

10-May 9740 344 7120 251 F 7120 251 -2620 -92.5

OAs for max. F-limit (maintain L. St. Louis at 22.33 m while L. Ont. >= 75.37 m & < 75.50 m, maintain Lake St. Louis at 22.40 m while Lake Ontario >= 75.50 m & < 75.60 m, maintain L. St. Louis at 22.48 m while L.Ont. >= 75.60 m)

17-May 9990 353 7250 256 F 7250 256 -2740 -96.8 OAs for max. F-limit (Maintain L. St. Louis at 22.48 m while L.Ont. >= 75.60 m)

24-May 10400 367 8060 285 F 8060 285 -2340 -82.6 OAs for max. F-limit (Maintain L. St. Louis at 22.48 m while L.Ont. >=75.60 m)

31-May 10560 373 8590 303 F 8590 303 -1970 -69.9 OAs for max. F-limit (Maintain L. St. Louis at 22.48 m while L.Ont. >= 75.60 m)

Note: The Op. Adjustments column values shown in this table are computed as the Actual Flow minus Adjusted RC Flow

15

Table 3a (continued): SUMMARY OF WEEKLY OUTFLOWS, OPERATIONAL ADJUSTMENTS AND DEVIATIONS

Week Ending 2019

Adj. RC Flow Plan Flow App. Rule/ Limit

Actual Flow Op. Adjustments

Deviations

Details Weekly Accumulated Cumulative

effect on L. Ontario

Type m3/s tcfs m3/s tcfs m3/s tcfs m3/s tcfs m3/s tcfs m3/s-

wks tcfs- wks cm in.

7-Jun 10720 379 9590 339 F 9590 339 -1130 -39.9 OAs for max. F-limit (Maintain L. St. Louis at 22.48 m while L.Ont. >= 75.60 m)

14-Jun 10730 379 10200 360 L 10300 364 -430 -15.2 100 3.5 100 3.5 -0.3 -0.1 Major (H14) Flow increased above Plan 2014 (deviations started) on 10 June

21-Jun 10790 381 10200 360 L 10400 367 -390 -13.8 200 7.1 300 10.6 -0.9 -0.4 Major (H14) Deviations continue 28-Jun 10780 381 10200 360 L 10400 367 -380 -13.4 200 7.1 500 17.7 -1.5 -0.6 Major (H14) Deviations continue 5-Jul 10880 384 10200 360 L 10400 367 -480 -17 200 7.1 700 24.7 -2.2 -0.9 Major (H14) Deviations continue

12-Jul 10800 381 10200 360 L 10400 367 -400 -14.1 200 7.1 900 31.8 -2.8 -1.1 Major (H14) Deviations continue 19-Jul 10700 378 10200 360 L 10400 367 -300 -10.6 200 7.1 1100 38.8 -3.4 -1.3 Major (H14) Deviations continue 26-Jul 10760 380 10200 360 L 10400 367 -360 -12.7 200 7.1 1300 45.9 -4.0 -1.6 Major (H14) Deviations continue 2-Aug 10680 377 10200 360 L 10400 367 -280 -9.9 200 7.1 1500 53 -4.6 -1.8 Major (H14) Deviations continue 9-Aug 10560 373 10200 360 L 10400 367 -160 -5.7 200 7.1 1700 60 -5.3 -2.1 Major (H14) Deviations continue

16-Aug 10420 368 9910 350 L 10400 367 -20 -0.7 490 17.3 2190 77.3 -6.8 -2.7 Major (H14) Deviations continue 23-Aug 10240 362 9910 350 L 10280 363 40 1.4 370 13.1 2560 90.4 -7.9 -3.1 Major (H14) Deviations continue 30-Aug 10200 360 9910 350 L 10110 357 -90 -3.2 200 7.1 2760 97.5 -8.5 -3.3 Major (H14) Deviations continue 6-Sep 9910 350 9910 350 R+ 10000 353 90 3.2 90 3.2 2850 100.6 -8.8 -3.5 Major (H14) Deviations continue

Note: The Op. Adjustments column values shown in this table are computed as the Actual Flow minus Adjusted RC Flow Note: The “+” in the App. Rule/Limit column denotes the Plan 2014 “September Rule” was applied. Whenever the Lake Ontario level is above 74.8 m at the beginning of September, the September Rule strives to lower Lake Ontario to 74.8 m by 1 January. The rule curve flow is linearly increased by the amount needed to eliminate the storage on the lake above 74.8 m over the remaining time, before 1 January. The adjusted flow is constrained by the L-limit.

16

Table 3b: SUMMARY OF FLOW CHANGES

Week Ending 2019

Flow Changes

Details Day Hr

(m3/s) (tcfs) Reason App. Rule/ Limit

From To From To

01-Mar 26-Feb 1601 8500 8600 300.2 303.7 OA I

Operational adjustment to max I-limit (Maintain L. St. Lawrence at 71.80 m)

27-Feb 1901 8600 8700 303.7 307.2 OA I

08-Mar -- -- -- -- -- -- OA I

15-Mar 9-Mar 0001 8700 8670 307.2 306.2 Plan RC Plan (Rule Curve)

22-Mar 16-Mar 0001 8670 8680 306.2 306.5 Plan RC

29-Mar 23-Mar 0001 8680 8820 306.5 311.5 Plan RC

26-Mar 0001 8820 8620 311.5 304.4 OA L Seaway opening, decrease to maximum L-limit

5-Apr -- -- -- -- -- -- Plan L Plan (maximum L-limit)

12-Apr 6-Apr 0001 8620 8680 304.4 306.5 Plan L Plan (maximum L-limit)

19-Apr

13-Apr 0001 8680 8710 306.5 307.6 Plan L Plan (maximum L-limit)

14-Apr 1201 8710 8400 307.6 296.6 OA F

Operational adjustments to max F-limit (Maintain L. St. Louis at 22.10 m; L. Ont. < 75.30 m)

15-Apr 0001 8400 8000 296.6 282.5 OA F

15-Apr 1401 8000 7600 282.5 268.4 OA F

18-Apr 2001 7600 7400 268.4 261.3 OA F

26-Apr 20-Apr 0001 7400 7000 261.3 247.2 OA F

20-Apr 1201 7000 6400 247.2 226 OA F

20-Apr 2001 6400 5900 226 208.4 OA F

22-Apr 1001 5900 5600 208.4 197.8 OA F

24-Apr 0001 5600 5800 197.8 204.8 OA F

24-Apr 1601 5800 6000 204.8 211.9 OA F

25-Apr 1201 6000 5700 211.9 201.3 OA F

26-Apr 1601 5700 5500 201.3 194.2 OA F Operational adjustments to max F-limit (Maintain L. St. Louis at 22.20 m, L. Ont. >= 75.30 m & < 75.37 m)

3-May

28-Apr 1601 5500 5900 194.2 208.4 OA F

Operational adjustments to max F-limit (Maintain L. St. Louis at 22.33 m; L. Ont. >= 75.37 m & < 75.50 m)

29-Apr 1301 5900 6100 208.4 215.4 OA F

2-May 1501 6100 6300 215.4 222.5 OA F

10-May

4-May 0001 6300 6500 222.5 229.5 OA F

4-May 1601 6500 6800 229.5 240.1 OA F

6-May 0001 6800 7000 240.1 247.2 OA F Operational adjustments to max F-limit (Maintain Lake St. Louis at 22.40 m; Lake Ontario >= 75.50 m & < 75.60 m)

7-May 0001 7000 7200 247.2 254.3 OA F

8-May 0001 7200 7400 254.3 261.3 OA F

8-May 1401 7400 7600 261.3 268.4 OA F

10-May 0001 7600 7400 268.4 261.3 OA F Operational adjustments to max F-limit (Maintain Lake St. Louis at 22.48 m; Lake Ontario >= 75.60 m) Note: Criterion H14 was exceeded as of week ending 10 May 2019; Board strategy to continue to follow Plan 2014 F-limit.

10-May 0901 7400 7000 261.3 247.2 OA F

17-May

11-May 0901 7000 7300 247.2 257.8 OA F

14-May 1801 7300 7100 257.8 250.7 OA F

16-May 2001 7100 7400 250.7 261.3 OA F

17-May 1401 7400 7600 261.3 268.4 OA F

17

Table 3b (continued): SUMMARY OF FLOW CHANGES

Week Ending 2019

Flow Changes

Details Day Hr

(m3/s) (tcfs) Reason App. Rule/ Limit

From To From To

24-May

19-May 0001 7600 7800 268.4 275.5 OA F

Operational adjustments to max F-limit (Maintain Lake St. Louis at 22.48 m; Lake Ontario >= 75.60 m)

21-May 0601 7800 8000 275.5 282.5 OA F

21-May 1501 8000 8100 282.5 286 OA F

22-May 0901 8100 8200 286 289.6 OA F

22-May 1601 8200 8400 289.6 296.6 OA F

23-May 1401 8400 8500 296.6 300.2 OA F

31-May 27-May 0001 8500 8600 300.2 303.7 OA F

31-May 0901 8600 8800 303.7 310.8 OA F

7-Jun

1-Jun 1201 8800 9000 310.8 317.8 OA F

2-Jun 1701 9000 9100 317.8 321.4 OA F

3-Jun 1101 9100 9400 321.4 332 OA F

3-Jun 1801 9400 9500 332 335.5 OA F

4-Jun 0901 9500 9800 335.5 346.1 OA F

5-Jun 2101 9800 10000 346.1 353.1 OA F

6-Jun 1001 10000 10200 353.1 360.2 OA F

14-Jun

10-Jun 0001 10200 10250 360.2 362 Dev Major (H14) Flows greater than Plan 2014 begin

11-Jun 0001 10250 10300 362 363.7 Dev Major (H14)

12-Jun 0001 10300 10350 363.7 365.5 Dev Major (H14)

13-Jun 0001 10350 10400 365.5 367.3 Dev Major (H14)

21-Jun -- -- -- -- -- -- Dev Major (H14)

28-Jun -- -- -- -- -- -- Dev Major (H14)

5-Jul -- -- -- -- -- -- Dev Major (H14)

12-Jul -- -- -- -- -- -- Dev Major (H14)

19-Jul -- -- -- -- -- -- Dev Major (H14)

26-Jul -- -- -- -- -- -- Dev Major (H14)

2-Aug -- -- -- -- -- -- Dev Major (H14)

9-Aug -- -- -- -- -- -- Dev Major (H14)

16-Aug -- -- -- -- -- -- Dev Major (H14)

23-Aug 21-Aug 0001 10400 10110 367.3 357 Dev Major (H14)

Continue major deviations flowing 10400 m3/s until Lake Ontario reaches 75.50 m; then reduce flows to 200 m3/s above applicable L-limit Lake Ontario reached 75.50 m on 19 Aug 2019

30-Aug -- -- -- -- -- -- Dev Major (H14) Remain at 10110 m3/s (L-limit + 200 m3/s)

6-Sep 31-Aug 0001 10110 10000 357 353.1 Dev Major (H14) L-limit + 200 m3/s = 10000 m3/s

18

Table 4 Lake Ontario Recorded and Preproject Levels and Outflows

Month Lake Ontario Monthly Mean Water Levels (IGLD 1985) - meters (feet)

Lake Ontario Monthly Mean Outflow m3/s (tcfs)

Recorded Preproject Diff. Recorded Preproject Diff.

Mar 19 74.97 (245.96) 75.69 (248.32) -0.72 (-2.36) 8690 (307) 8270 (292) 420 (15)

Apr 19 75.15 (246.55) 75.84 (248.82) -0.69 (-2.27) 7450 (263) 8800 (311) -1350 (-48)

May 19 75.70 (248.36) 76.10 (249.67) -0.40 (-1.31) 7600 (268) 9380 (331) -1780 (-63)

Jun 19 75.91 (249.05) 76.23 (250.10) -0.32 (-1.05) 10190 (360) 9670 (341) 520 (18)

Jul 19 75.80 (248.68) 76.23 (250.10) -0.43 (-1.42) 10400 (367) 9670 (341) 730 (26)

Aug 19 75.53 (247.80) 76.08 (249.60) -0.55 (-1.80) 10290 (363) 9340 (330) 950 (34)

Table 5 Attendance at Face to Face

Meetings

Board Member

Country

6 March

MG M. Toy1 US - Dr. G. Bechard2 Can. X Mr. J. Aubry-Morin Can. X Mr. T. Brown US X Mr. R. Campany US X Ms. P. Clavet Can. X

Mr. T. David US X Mr. S. Durrett3 US X Ms. J. Frain Can. X Mr. M. Hudon Can. X Dr. D. Keuhn US X

Notes: 1. US Co-Chair 2. Canadian Co-Chair 3. US Alternate chair

Location of Meeting: 6 March 2019: Syracuse, NY, US

19

105,942

141,256

176,570

211,884

247,198

282,512

317,826

353,140

388,454

423,768

3,000

4,000

5,000

6,000

7,000

8,000

9,000

10,000

11,000

12,000

J F M A M J J A S O N D

Supp

lies

(cfs

)

Supp

lies

(m3 /s

)

Month

Figure 1: Monthly Net Total Supplies to Lake Ontario

2017 2018 2019 AVG 1900-2018 MIN MAX

20192017

2018

14,126

49,440

84,754

120,068

155,382

190,696

226,010

261,324

296,638

331,952

367,266

400

1,400

2,400

3,400

4,400

5,400

6,400

7,400

8,400

9,400

10,400

1-Jan 29-Jan 26-Feb 25-Mar 22-Apr 20-May 17-Jun 15-Jul 12-Aug 9-Sep 7-Oct 4-Nov 2-Dec 30-Dec

Flow

(cfs

)

Flow

(m3 /s

)

Figure 2: Daily Ottawa River Flow @ Carillon

2017 2018 2019 AVG 1963-2018 MIN MAX

2019

2018

2017

20

141,258

158,915

176,572

194,229

211,886

229,543

247,200

264,857

282,514

300,171

317,828

335,485

353,142

370,799

4000

4500

5000

5500

6000

6500

7000

7500

8000

8500

9000

9500

10000

10500

Out

flow

s (c

fs)

Out

flow

s (m

3 /s)

Month

Figure 3: Lake Ontario Daily Outflows

2017 2018 2019 Average (1900-2018) Max Min

Max 2017

Min 1936

2017

2018

2019

141,258

158,915

176,572

194,229

211,886

229,543

247,200

264,857

282,514

300,171

317,828

335,485

353,142

370,799

4000

4500

5000

5500

6000

6500

7000

7500

8000

8500

9000

9500

10000

10500

Out

flow

(cfs

)

Out

flow

(m3 /s

)

Month

Figure 4: Lake Ontario Actual, Preproject & Plan 2014 Outflows

Preproject Plan 2014 Flow Actual AVG 1900-2018 MAX MIN

Min 1936

Max 2017

21

238.5

239.5

240.5

241.5

242.5

243.5

244.5

245.5

246.5

247.5

248.5

249.5

250.5

251.5

72.7

73.0

73.3

73.6

73.9

74.2

74.5

74.8

75.1

75.4

75.7

76.0

76.3

76.6

Leve

ls (f

t.)

Leve

ls (m

)

Month

Figure 5: Daily Lake Ontario Water Levels

2017 2018 2019 AVG 1918-2018 MIN MAX

Max 2017

Min 1934

1918-2018 monthly values, overall range 2.07 m (6.8 ft.)

2019

2018

2017

Plan 2014Crit. H14 high thresholds

Plan 2014Crit. H14 low thresholds

238.5

239.5

240.5

241.5

242.4

243.4

244.4

245.4

246.4

247.4

248.4

249.3

250.3

251.3

72.7

73.0

73.3

73.6

73.9

74.2

74.5

74.8

75.1

75.4

75.7

76.0

76.3

76.6

Leve

ls (f

t.)

Leve

ls (m

)

Month

Figure 6: Lake Ontario Actual, Preproject & Plan 2014 Levels

Preproject Plan 2014 Actual AVG 1918-2018 MIN MAX

Plan 2014Crit. H14 high thresholds

Plan 2014Crit. H14 low thresholds

Min 1934

Max 2017

22

232.9

233.9

234.9

235.9

236.9

237.9

238.9

239.9

240.9

241.9

242.9

243.9

244.9

245.9

71.0

71.3

71.6

71.9

72.2

72.5

72.8

73.1

73.4

73.7

74.0

74.3

74.6

74.9

J F M A M J J A S O N D

Leve

ls (f

t.)

Leve

ls (m

)

Month

Figure 7: Daily Lake St. Lawrence Levels @ Long Sault Dam

2017 2018 2019 Chart Datum AVG 1960-2018 MIN MAX

1960-2018 monthly values, overall range 2.61 m (8.6 ft.)

Min 1978

Max 1973

Chart Datum 72.5 m (237.9 ft.)

2019

2018

2017

I-Limit threshold 71.8 m (235.6 ft.)

L-Limit threshold 72.6 m (238.2 ft.)

63.7

64.7

65.7

66.7

67.7

68.7

69.7

70.7

71.7

72.7

73.7

74.7

75.7

76.7

19.4

19.8

20.2

20.6

21.0

21.4

21.8

22.2

22.6

23.0

23.4

J F M A M J J A S O N D

Leve

ls (f

t.)

Leve

ls (m

)

Month

Figure 8: Daily Lake St. Louis Levels @ Pointe-Claire

2017 2018 2019 Chart Datum AVG 1960-2018

MIN Seaway Low Alert Flood Alert Flood Stage MAX

1960-2018 monthly values, overall range 2.20 m (7.2 ft.)

Min 1965

Max 1974

Chart Datum 20.351 m (66.8 ft.)

Seaway Low Alert 20.60 m (67.6 ft.)

Flood Alert 22.10 m (72.5 ft.)

Flood Stage 22.33 m (73.3 ft.)2019

20182017

M limit threshold

F limit thresholds

23

16.7

17.7

18.7

19.7

20.7

21.7

22.7

23.7

24.7

25.7

26.7

27.7

28.7

29.7

5.1

5.4

5.7

6.0

6.3

6.6

6.9

7.2

7.5

7.8

8.1

8.4

8.7

9.0

J F M A M J J A S O N D

Leve

ls (f

t.)

Leve

ls (m

)

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Figure 9: Daily Port of Montreal Levels @ Jetty #1

2017 2018 2019 Chart Datum AVG 1967-2018 MIN MAX

Max 1967

Min 2012

1967-2018 monthly values, overall range 3.83 m (12.6 ft.)

Chart Datum 5.55 m (18.2 ft.)

2019 2018

2017

11.2

12.2

13.2

14.2

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3.4

3.9

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ls (f

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)

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Figure 10: Daily Lake St. Peter Levels @ Sorel

2017 2018 2019 Chart Datum Average 1984-2018 Min Max

Max 2017

Min 2012

1984-2018 monthly statistics, overall range 3.01 m (9.9 ft.)

2017

2018

2019

Chart Datum 3.78 m (12.4 ft.)

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Appendix A: Communications Committee Summary of Activities Since 1 March 2019, the International Lake Ontario - St. Lawrence River Board Communications Committee held 17 meetings via teleconference. The Committee continued to engage in initiatives and develop products to accomplish five strategic communication goals:

• increase general public awareness of the IJC and the Board; • communicate accurately and in a timely fashion the actions of the Board and the reason for

those actions; • explain how natural factors and regulation affect water levels and flows; • increase understanding of the necessity of and need to prepare for fluctuations in levels

and flows; and • consistently seek out, consider and respond to the views and concerns of all stakeholders.

Starting in March, a total of 16 media releases were published, distributed and posted on the Board’s website. Many additional posts on the Board’s Facebook page addressed issues of concerns to those on the page. Board Members, Secretaries and Regulation Representatives provided countless interviews with a wide variety of news agencies in the US and Canada throughout the reporting period. Interviews were provided to print, radio and TV agencies, and generally focused on what actions the Board was taking to help alleviate the impacts shoreline property owners were experiencing due to the high water. Some of the agencies that conducted interviews with Board Associates were: Spectrum News, North County Public Radio, WHAM TV in Rochester, the Wall Street Journal, the Palladium Times, and the Lockport Journal.

The Board engaged with radio station WXXI in New York to provide representation on a live radio show with Board member Mr. David and Commissioner Corwin participating. The show “Connections with Evan Dawson” was aired on Friday, July 19. The show was comprised of a series of interview questions and a few questions taken from the listening audience.

The IJC contracted with ECOStrategy to assist the Board in communications from May to June. They were helpful in identifying the trending concerns on social media and highlighting news worthy articles related to the Board’s activities. They also provided advice on the effectiveness of the Communications Committee’s press releases and social media posts. In addition to all the media engagement, Board members and representatives were very busy with personal engagement. Hundreds of email replies were sent to concerned individuals through the IJC’s web page contact form. These responses were crafted with the intent to dispel misinformation about the effects of regulation on the system and explain the causes of this year’s high water event. Board members and representatives also actively engaged stakeholders by presenting at or attending the following venues where they answered questions and concerns from those present:

4 March South Nation Conservation, Finch, Ontario 9 May North Rainbow Shores Road Association, South Sandy Pond, NY 9 May Preparedness Planning Workshop, Wolcott, NY 14 May Wilson Hill Association, Louisville, NY 28 May Meeting with IJC Commissioners and elected officials: Greece, NY 5 June Tour of the Toronto Islands; IJC Commissioners and staff, Board member;

City of Toronto and TRCA staff 10 June Meeting with local officials, Greece, NY

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24 June Village Protection Structure, Sodus Point, NY 26 June Meeting with Local Officials, Ogdensburg, NY 27 June Fairhaven Official and NY Sea Grant, Fairhaven, NY 29 July REDI Commission, Oswego, NY 13 August REDI Commission,Oswego, NY 27 August Meeting with MPs, MPPs and Local Canadian Mayors, Brockville, Ontario 29 August REDI Commission, Oswego, NY

The Canadian Regulation Representative provided regular water condition updates with provincial water managers, conservation authorities and municipalities in Ontario. The US Regulation Representative participated in regular teleconferences addressing the emergency high water levels in New York State.

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Appendix B: Communications Committee Membership

Mr. R. Campany Mr. M. Hudon Mr. T. David Mr. R. Caldwell Mr. F. Bevacqua Mr. J. Bruxer Mr. B. Carmichael Ms. S. Lobrichon Mr. W. Werick Mr. D. Fay Mr. A. Kornacki Ms. W. Leger Mr. M. Shantz

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Appendix C:

FACEBOOK SUMMARY REPORT 1 March – 31 August 2019

During the six-month period from 1 March to 31 August 2019, the Board’s staff continued its outreach on its Facebook page, posting weekly updates, explanations, and answering general queries. Its Facebook community responded with questions and comments, especially once water levels on Lake Ontario rose sharply in mid-April. The Board maintains separate English and French Facebook pages, with most of its posts appearing on both pages. The English page gets more activity than does the French page. We analysed the Board’s English Facebooks posts during the six month period to investigated trends and performance. An excel spreadsheet records the data for all the posts from 1 March to 31 August 2019. For each post, the analysis identifies the type, records the date and Facebook statistics. The nature of the comments from the Facebook community to the posts are mentioned for the exceptional post. The following sections discuss the types of Board posts to the Facebook page, the statistics, and the nature of the responses from the Facebook community posting to the Board’s English page. Types of Board Posts The analysis identified four types of posts among the 108 posts of the Board to its Facebook page from 1 March to 31 August 2019, which are described in turn below.

Media Releases The Board announces its media releases, which appear in full on its website, on the Facebook page. An early media release of 4 March announced that high outflows would continue despite low water levels in Lake St. Lawrence. The next media release on 26 April announced the expectation that water levels would rise throughout the Lake Ontario – St. Lawrence River system. With the full-blown onset of the high water crisis, the frequency of the media releases increased to a total of 14 from 4 March to 23 August, usually after every Board conference call. The media releases garnered the most interest, as ascertained from the statistics described in the next section, from the Facebook community.

YAWA After 11 June, the Board started posting “#You Ask, We Answer ILOSLRB #2019 High Water Facts” (YAWA) every few days to ease the burden on Board staff to respond directly to each comment or question from the Facebook community. A total of 26 YAWAs were posted. Many were framed as questions and answers, nine contained graphics, such as a diagram or video. Despite the shorter duration for the YAWAs (two and half months) and short frequency (many were posted one day or less apart), they received the largest number of comments from the Board’s Facebook community . Weekly Water Updates At the start of the period, six weekly water updates included a brief narrative accompanied by plots of water levels and flows at various points in the Lake Ontario – St. Lawrence River system. In mid-April, the Board’s website carried interactive plots, so the weekly water updates were given as values on dials shown on a map of the system for the various points while pointing to the plots on the website. The Board posted a total of 31 weekly updates from 7 March to 28 August 2019 on Facebook. The Facebook community often voiced their appreciation of the weekly water update posts.

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General Posts From 8 March to 8 August 2019, the Board posted 37 general posts explaining hydrological phenomena like lake effect snow, Great Lakes water levels and weather conditions; Board and IJC visits to Greece, planning offices and the Toronto Islands and 16 flow change announcements. The flow change announcements were most frequent (daily and at times twice a day) from the middle of May to early June. The general posts, despite their largest percentage of the types of posts, received the least interest, as ascertained from the statistics described in the next section, from the Facebook community.

Facebook Statistics The analysis tracked four statistics readily available to the administrator of the Board’s English Facebook page as listed for each post of the 108 posts between 1 March to 31 August 2019. The analytical statistics are as follows:

Facebook Reach is the number of unique people who saw content from the LOSLRB page or about the page enter their screen. Facebook engagement is any action someone takes on the LOSLRB page or one of its posts. The most common examples are likes, comments, and shares, but it can also include checking in to the location or tagging ILOSLRB in a post. Comments are posts from the Facebook community, including Board responses, in reaction to the 108 Board posts. Shares are when someone in the Facebook community forwards the Board’s post to someone else. Reach The reach for any post during the period was always greater than any of the other statistics, with the post with the highest reach not always recording the highest engagement, number of comments nor shares. Except for the general posts, the engagement ratio, the percentage of the engagement to the reach, was in the order of a quarter to a third (the ratio for general posts was slightly over half). The posts with the highest reach were a weekly water update (19 April) at 22,083 when the Ottawa River was in full freshet; a YAWA about the peaking of Lake Erie (29 July) at 21,856; a media release announcement (26 April) at 21,694 warning of rising water levels and a flow change post (16 May) at 10,193, when the outflows started to increase again after the Ottawa River freshet had passed. The average reach for all the Media Release announcements, YAWAs, and weekly water updates was about a third of the maximum, the average reach for the general posts were almost two thirds of the maximum. The average reach for all posts, of whatever type, was close to 7000. Engagement The posts with the highest engagements were the same media release announcement (26 April) at 6,461; the same weekly water update (19 April) at 5,674; a post about the IJC meeting in Greece NY (28 May) at 5,383 and a YAWA explaining why more water wasn’t released during the winter of 2018 (11 June). The average engagement for all posts of whatever type was 2335, or also about a 33% engagement to reach ratio. Comments The total number of comments to the Board’s 108 posts over the period was 14,163 for an average of 131 per post. This number of comments is far less than either the reach or the engagement per post, in the order 6% of the engagement numbers per post. Given that the same person (and the Board) may be reacting to the same post a number of times, the number of commenters is even less. However it means that the Board’s messages are reaching far more people than those who are commenting on its page. The posts with the maximum number of comments are, by type, the last YAWA about why the Board

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reduced outflows for shipping (24 August) at 389; media release announcements warning of rising water levels (26 April) at 349; a general post on water levels of the Great Lakes (8 May) at 266 and a weekly water update (14 May) during the Ottawa River freshet at 250. The average number of comments per post is less than half the maximum number per post. Interestingly, not all the comments relate to the content of the 108 Board posts. Shares Another interesting statistic is the number of shares per post. The total number of shares of the Board’s 108 posts over the period was 4,428 for an average of 41 per post. Often a post, which the other statistics indicate had a high interest, also has a high number of shares, and for eight posts even more shares than comments (nine more posts where the number of shares were within 10 of the number of comments). Thus further evidence that the comments are the tip of the iceberg of the Board’s English Facebook page outreach. The posts with the maximum number of shares are, by type, the media release announcements warning of rising water levels (26 April) at 351; the first weekly water update with a map (19 April) at 126; a YAWA about the Plan 2014 L-Limit (14 August) at 111; and a general post on water levels of the Great Lakes (12 April) at 66. The average number of shares per post is far less than the maximum number per post. Posts with videos or graphics are more likely to be shared.

Comments on Posts As mentioned in the preceding section on the statistics, the Facebook Pages are reaching and engaging many more people than those who comment on its pages. The percentage of comments is only 6% of the number of engagements and many of its most popular posts were shared to over or close to 100 others. There are many different viewpoints represented in the comments section following Board posts. Some individuals are supportive of the messaging, some are inquisitive and seek additional information and some disagree with the Board’s messaging. The comments section remains a vehicle for people to voice their opinions and engage in discussion. Conclusion Overall, the Board’s outreach through its English Facebook page during the period 1 March to 31 August 2019 saw more activity during the rapid rise of the water levels of Lake Ontario and when the outflow was lowered in August.

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