FINAL REPORT - International Joint Commission

ANNEX 2
74.1 m (243.0 ft). Three facilities along the St. Lawrence River upstream of the Moses-Saunders Dam
(Ogdensburg, Morristown and Ingleside) reported critical elevations of 73.2, 71.6 and 71.2 m (240.0,
235.0 and 233.6 ft) respectively. When comparing with the record low, Albion (N.Y.) was the only facility
along Lake Ontario that reported a critical elevation above this level. In general, most interviewees agreed
that variations within long-term averages do not have a substantial impact on the ability of water treatment
plants to effectively supply water. The one exception was the Monroe County Water Authority drinking
water plant that did report impacts by high water levels which could flood the pumping station. The loss
of the pumping station would stop delivery of water to about 650,000 customers. While the Water
Authority did not quantify the damages associated with high water level situations, preliminary investigations
show that the Authority has avoided this in the past by sandbagging the plant, that water levels that
provoke sandbagging will occur a few times a century under the current plan, and that no matter what
regulation plan the International Joint Commission selects, Lake Ontario levels will be a few feet higher
than the sandbag trigger level during the most extreme wet periods.
On the other hand, low water levels appear to be a significant concern for industrial, and in particular power
generation facilities, for two reasons: 1) they affect shipments of raw material including coal, and 2) low
water levels can impact intake structures causing loss of pressure for vital cooling systems and may expose
intakes to other conditions such as frazil ice that can also threaten cooling systems. Three facilities along
Lake Ontario reported a critical low water elevation for adequate head over cooling water intakes: 1) the
Russell Coal-Fired Power Station in New York (74.37 m/244.00 ft) and 2), Ginna Nuclear Plant near
Rochester, New York (74.37 m/244 ft), and 3) the Darlington Nuclear Station in Ontario (72.0 m/236.22 ft).
Both Ginna and Russell, located on the south shore of Lake Ontario, would experience problems within the
historical record, and will require upgrading to remain fully operational under high and low water level
conditions in the future under any plan, including the existing one. Low level problems are not a problem
for the Darlington plant under any plan or supply sequence scenario evaluated, including the climate
change scenarios.
Wastewater treatment plants and outfalls
Of the 79 facilities that responded to the survey, 32 reported critical water elevations. The remaining
facilities either left the question blank or specifically indicated that they did not know or have the information.
Low critical levels for Lake Ontario range from 74.37 m (244.00 ft) to 67.12 m (220.22 ft). Only two
facilities reported low critical levels above the Lake’s record low (73.73 m/241.90 ft), and only one facility
noted critical low levels above the lower bound (74.15 m/243.30 ft) of the IJC Orders of Approval.
High critical elevations for facilities along Lake Ontario range from 80.16 m (263.00 ft) to 75.59 m
(248.00 ft). Only three facilities reported critical high levels that are below the Lake’s record high of
75.80 m (248.69 ft), and none reported levels that were below the upper bound of the IJC Orders of
Approval (i.e., the regulation plan) of 75.37 m (247.29 ft).
Similar to the case on Lake Ontario, critical high water levels at most facilities along the River are relatively
high—between 4.14 m (13.58 ft) and 1.05 m (3.44 ft) above datum—while low critical levels are from
0.73 m (2.40 ft) to 15.42 m (50.59 ft) below datum.
Domestic uses
Source water elevation can and does affect self-supplied residential water systems, including shore wells
and water intake lines; however, the number of people who use self-supplied systems is small relative to
populations served by water utilities.
126 Options for Managing Lake Ontario and St. Lawrence River Water Levels and Flows