5. Lake Ontario



(1) Chart Datum, Lake Ontario.-- Depths and vertical clearances under overhead cables and bridges given in this chapter are referred to Low Water Datum, which for Lake Ontario is an elevation 243.3 feet (74.2 meters) above mean water level at Rimouski, Quebec, on International Great Lakes Datum 1985 (IGLD 1985). (See Chart Datum, Great Lakes System, indexed as such, chapter 1.)

Dimensions, etc.
(2) Length, steamer track, Burlington Bay Light to head of St. Lawrence River (Tibbetts Point); 180 miles.
(3) Length, steamer track, Port Dalhousie to head of St. Lawrence River (Tibbetts Point); 160 miles.
(4) Length (right line), W end of Burlington Bay to Sackets Harbor; 193 miles.
(5) Breadth (right line), about longitude 77 35'W.; 53 miles.
(6) Depth, maximum recorded by NOS; 802 feet.
(7) Water surface of lake (including Niagara River and St. Lawrence River above Iroquois Dam); 3,560 square miles (U.S.), 3,990 square miles (Canada).
(8) Entire drainage basin (including Niagara River and St. Lawrence River above Iroquois Dam); 18,760 square miles (U.S.), 16,090 square miles (Canada).

(9) General description.-Lake Ontario is the smallest and easternmost of the Great Lakes. The lake is comparatively deep; the greatest depth is 802 feet, and the average depth is 283 feet, much in excess of the greatest depth of Lake Erie. Lake Ontario is fed chiefly by the waters of Lake Erie by way of the Niagara River. The lake drains at its NE end into the St. Lawrence River. Welland Canal bypasses the falls and rapids of the Niagara River and provides a navigable connection between Lake Ontario and the upper lakes.

(10) The great depth of the lake limits fluctuations of water level caused by winds and renders them comparatively small. The lake is generally free of outlying shoals and obstructions. The only significant shoals dangerous to navigation are those in the NE end of the lake in the approach to the St. Lawrence River and those of Niagara Bar off the mouth of the Niagara River. The latter shoal is in the course of vessels plying between the Welland Canal and ports at the E end of the lake.

(11) The waters of Lake Ontario and the Welland Canal are part of the St. Lawrence Seaway and are under the navigational control of the Saint Lawrence Seaway Development Corporation, a corporate agency of the United States, and the Saint Lawrence Seaway Authority of Canada. These agencies issue joint regulations covering vessels and persons using the Seaway. The regulations are codified in 33 CFR 401, and are also contained in the Seaway Handbook, published jointly by the agencies. A copy of the regulations is required to be kept on board every vessel transiting the Seaway. A schedule of the Seaway tolls is contained in the handbook. (See St. Lawrence Seaway, chapter 3, and 33 CFR 401, chapter 2.)

(12) Vessels bound for Lake Ontario from the St. Lawrence River below Montreal are limited by the size of the locks in the river, and vessels bound from Lake Ontario to the upper lakes are limited by the size of the locks in the Welland Canal. The maximum authorized dimensions for vessels navigating the St. Lawrence Seaway locks are 730 feet overall length, 76 feet extreme breadth, and 26 feet draft. (For complete information on vessel dimension restrictions, refer to the Seaway Handbook, and for supplemental information, to the Seaway Notices.)

(13) Vessel traffic control.-- Lake Ontario and the Welland Canal are divided into three traffic control sectors, with vessel movements in each sector controlled by a traffic controller. The objective of the system is to provide safe and efficient scheduling of vessel traffic, efficient search and rescue coverage, information regarding pilot requirements to the pilot dispatch centers, marine weather broadcasts, and information on vessel location to all interested parties.

(14) The traffic control sectors are as follows: Sector 4, from Crossover Island in the St. Lawrence River to midlake in Lake Ontario; Sector 5, the W half of Lake Ontario; Sector 6, Welland Canal and its approaches.

(15) Massena traffic control center controls traffic in the Lake Ontario portion of Sector 4 through "Seaway Sodus," VHF-FM channel 13. St. Catharines traffic control center controls traffic in Sector 5 through "Seaway Newcastle," VHF-FM channel 11, and in Sector 6 through "Seaway Welland," VHF-FM channel 14.

(16) Calling-in points.-- Calling-in points on Lake Ontario follow:

(17) Calling-in point Sodus Point.-- Upbound and downbound vessels shall contact "Seaway Sodus" on VHF-FM channel l 3 when approximately abeam of Point Petre, Ont. After initial contact, vessels shall guard VHF-FM channel 16.

(18) Calling-in point Mid-Lake Ontario.-- Upbound vessels shall contact "Seaway Newcastle" on VHF-FM channel 11 and downbound vessels shall contact "Seaway Sodus" on VHF-FM channel 13 upon arrival at a point in mid-lake in about 43 41'N., 77 47'W. After initial contact, vessels shall guard VHF-FM channel 16.

(19) Calling-in points Newcastle.-- Upbound and downbound vessels shall contact "Seaway Newcastle" upon arrival at a point about 16 miles S of Newcastle, Ont., and when about 8 miles N of Thirtymile Point, N.Y. on VHF-FM channel 11. After initial contact, vessels shall guard VHF-FM channel 16.

(20) Complete information on the traffic control sectors and their respective calling-in points is contained in the Seaway Handbook.

(21) Fluctuations of water level -- The normal elevation of the lake surface varies irregularly from year to year. During the course of each year, the surface is subject to a consistent seasonal rise and fall, the lowest stages prevailing during the winter and the highest during the summer. In addition to the normal seasonal fluctuations, oscillations of irregular amount and duration are also produced by storms. Winds and barometric pressure changes that accompany squalls can produce fluctuations that last from a few minutes to a few hours. At other times, strong winds of sustained speed and direction can produce fluctuations that last a few hours or a day. These winds drive forward a greater volume of surface water than can be carried off by the lower return currents, thus raising the water level on the lee shore and lowering it on the windward shore. This effect is more pronounced in bays and at the extremities of the lake, where the impelled water is concentrated in a small space by converging shores, especially if coupled with a gradually sloping inshore bottom which even further reduces the flow of the lower return currents.

(22) Lake Ontario has less of a seiche problem than some of the other lakes. These irregular oscillations of the water surface are less pronounced in range because of the lake's smaller area and deep water along with a general symmetrical shape. There is also a lesser number of high- and low-pressure centers that pass directly over the lake.

(23) Weather.-- Navigation-season winds are strongest in autumn. Gales are most likely from October through December and blow out of the SW through NW. This is particularly true at the E end of the lake, where a funneling effect may occur with W and SW winds, which prevail throughout most of the year. As these winds encounter land, on either side of the lake, near theThousand Islands, they are accelerated. A moderate blow in mid-lake often becomes a dangerous gale in this restricted area. Another local problem area is Mexico Bay, N of Oswego. This was once known as "the graveyard of Lake Ontario" because ships foundered there in NW through NE winds. In spring, northeasterlies and easterlies occasionally reach gale force throughout the lake. May through August is often the most troublefree time; windspeeds of 16 knots or less are encountered 80 percent or more of the time. The strongest sustained measured wind on the lake was west-north-westerly at 50 knots. This short period record (17 years) occurred in November. Since extremes along the shore range from 50 to 65 knots, it could be expected that an extreme on the lake could reach 90 knots. The prevailing SW and W winds are most persistent in winter and summer. Winds with northerly components are also common in winter as are those with southerly components in summer. Autumn and spring winds are more variable.

(24) While visibilities are restricted by rain, snow, haze, and smoke, fog is the most frequent and troublesome cause. On Lake Ontario, prolonged periods of rain and foggy weather are common when frontal systems moving into New York become stationary. In the spring, advection fog reduces visibilities to below 0.5 mile up to 10 percent of the time. It is usually worst during the morning hours. Along the shore, radiation fog is common in autumn under calm, clear nighttime skies. This fog sometimes drifts cut over the water; it usually burns off by noon. Visibilities of 2.5 miles or less occur on about 10 to 13 days per month from October through March along the shore.

(25) While rough seas can be encountered in any season, they are most often a problem during fall and winter. From October through February, wave heights of 5 feet or more can be expected 10 to near 20 percent of the time and 10 feet or more up to 2 percent of the time. Extreme wave heights of 17 to 19 feet have been encountered. Since strong winds over a long fetch of water are conducive to creating rough seas, strong winds out of the E and W quadrants over Lake Ontario are often danger signals. Sea conditions are best from May through July when waves of less than 1 foot occur 50 percent or more of the time.

(26) Thunderstorms can occur at any time, but are mostly a summertime problem. Along the shore, they are recorded on 20 to 30 days annually; about 75 percent or more brew up from May through September. They are most likely during the late afternoon. Over the open lake, thunderstorms are most likely during August when they occur about 2 percent of the time. Summertime thunderstorms are mostly nocturnal creatures over the lake; they are most frequent between sunset and sunrise.

(27) Ice.-- The main part of Lake Ontario usually remains open throughout the winter, with only a few patches of thin ice and slush during cold spells. Its small area and great depth give Lake Ontario a large heat storage capacity. In addition, the land portion of the basin contributes more runoff to its lake than any of the other lakes. These factors retard the growth of ice in fall and aid its rapid decay in spring. During a normal winter, early ice cover appears toward the end of January and early decay begins in mid-March. During severe winters, extensive slush develops for brief periods, but the significant ice is confined to the E end of the lake. E of Prince Edward Point, ice formation begins in early January. The area from Kingston to Prince Edward Point and Oswego is usually covered 70 to 90 percent with thin and medium lake ice by the end of the month. This thickness increases during February and reaches the thick category by early March, but the extent is unchanged except for drifting patches of slush along the Canadian shore. By this time, fast ice about 20 to 25 inches thick usually extends in a N are from Prince Edward Point to Stony Point. Decay generally develops in early March, and by the third week most of the pack has melted in place rather than drifting down the river. (See Winter Navigation, chapter 3.)

(28) Local magnetic disturbances.-- Differences from normal variation of from about 006 W to 007 E have been observed at numerous locations throughout Lake Ontario. Differences of up to 37 have been observed in the approach to Kingston, Ont., on the N side of the head of the St. Lawrence River. The locations of these anomalies are shown on NOS chart 14500.

(29) Routes.-- The Lake Carriers' Association and the Canadian Shipowners Association have recommended, for vessels enrolled in the associations, the following separation of routes for upbound and downbound traffic in Lake Ontario.

(30) Downbound vessels from Port Weller to Cape Vincent from a position 0.5 mile off Port Weller breakwaters, shall lay a course of 048 for 8.5 miles to pass not more than 1.5 miles off Niagara Bar Lighted Buoy 2; thence 074 for 103 miles to a position not less than 7 miles off Point Petre; thence 069 for 27 miles to a position 3.5 miles to East Charity Shoal Traffic Lighted Buoy.

(31) Downbound vessels from Toronto, Port Credit, or Clarkson from a position not less than 2.5 miles off Gibraltar Point shall lay a course 085 113.75 miles to a position not less than 7 miles off Point Petre; thence recommended downbound courses of 069 and 039 to East Charity Shoal Traffic Lighted Buoy.

(32) Downbound vessels from Port Weller to Toronto, from a position 0.5 mile off Port Weller breakwaters, shall lay a course of 314 for 4 miles; thence 349 for 20 miles to a position not less than 3.8 miles off Toronto Main Harbour Channel range front light.

(33) Downbound vessels from Port Weller to Hamilton, from a position 0.5 mile off Port Weller breakwaters, shall lay a course 314 for 4 miles; thence 273 for 25 miles to Burlington Canal Entrance Lighted Bell Buoy MH.

(34) Upbound vessels from Cape Vincent to Port Weller, from East Charity Shoal Traffic Lighted Buoy, shall lay a course 240 for 14.5 miles to a position 0.5 mile off Psyche Shoal Lighted Bell Buoy 12; thence 249 for 22.5 miles to a position not more than 3 miles off Point Petre; thence 254 for 102 miles to a position not less than 5.5 miles off Niagara Bar Lighted Buoy 2; thence 212 for 11.25 miles to a position 0.5 mile off Port Weller breakwaters.

(35) Upbound vessels from Cape Vincent to Toronto, Port Credit, and Clarkson, from a position not more than 3 miles off Point Petre, shall lay a course of 263 for 113.25 miles to a position more than 2.8 miles off Toronto Main Harbour Channel range front light; thence to destination.

(36) Upbound vessels from Toronto to Port Weller, from a position not less than 3.8 miles off Toronto Main Harbour Channel Range Front Light, shall lay a course 163 for 23.5 miles to a position 0.5 mile off Port Weller breakwaters.

(37) Upbound vessels from Hamilton to Port Weller, from a position 0.5 mile off Burlington piers, shall lay a course 098 for 28.7 miles to a position 0.5 mile off Port Weller breakwaters.

(38) It is understood that masters may exercise discretion in departing from these courses when ice and weather conditions are such as to warrant it. The recommended courses are shown on chart 14800, Lake Ontario.

(39) Caution.-- A special use airspace is in midlake in U.S. waters bounded by the following coordinates:
(40) 43 37'N., 76 45'W.;
(41) 43 24'N., 76 45'W.;
(42) 43 24'N., 78 00'W.; and
(43) 43 37'N., 78 00'W.

(44) The area may be used for military purposes from the surface to an altitude of 50,000 feet. The using agency is the Commander, 21st Air Div., Hancock Field, Syracuse, N.Y. Consult Local Notice to Marines for additional information and firing schedules.

(45) Pilotage.-- The waters of Lake Ontario are Great Lakes undesignated waters; registered vessels of the United States and foreign vessels are required to have in their service a United States or Canadian registered pilot or other officer qualified for Great lakes undesignated waters. The Welland Canal and its approaches are Great Lakes designated waters; registered vessels of the United States and foreign vessels are required to have in their service a United States or Canadian registered pilot. Registered pilots for Lake Ontario and Welland Canal are supplied by the Great Lakes Pilotage Authority, Ltd., St. Catharines. (See appendix for address.) Pilot exchange points are off Cape Vincent, N.Y., 1 to 2 miles N of Port Weller, and at the S end of Welland Canal 1 to 2 miles S of Port Colborne. (See Pilotage, chapter 3, and 46 CFR 401, chapter 2.)

(46) Principal ports.-- The principal ports on Lake Ontario are at Oswego and Rochester, N.Y., and at Hamilton and Toronto, Ont. These harbors have been improved by dredging by the United States and Canadian governments, respectively, and provide access for vessels up to 26-foot draft. At Cape Vincent, N.Y., a harbor protected by a breakwater provides refuge for vessels who find that storm conditions render it unsafe to venture into the open lake from the head of St. Lawrence River. The largest drydock on Lake Ontario is at Port Weller in the Welland Canal.


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