(3) Channel enlargement in the North and South Channels at Cornwall Island.

Canadian section.

(1) In Lake St. Francis, channel enlargement where necessary.

(2) Modification of existing bridges across the 16-mile Beauharnois power (seaway) canal, channel enlargement therein as necessary, together with construction of a short section of new canal with two locks, upper Beauharnois and lower Beauharnois, and appurtenances to carry navigation around the powerhouse at the present lower end of the canal.

(3) On the south side of the river opposite Montreal, bypassing the Lachine Rapids, construction of an 18-mile lateral (Laprairie Basin) canal containing two locks, Cote Ste. Catherine and St. Lambert, together with appurtenant work including major bridge and utility alterations.

BASIC DIMENSIONS, LAKE ERIE TO MONTREAL SEAWAY

Controlling channel depth.

Controlling channel bottom width (open-river reaches).

Normally these dimensions are at least 600 feet. Bottom width in lateral canals will vary from 192 feet in the Welland Canal to 442 feet in Long Sault Canal.

Maximum current anticipated in dredged cuts.

Locks:

Number of lift locks requiring transit..
Length between gate hinges generally.
Controlling inner length, gate to fender.
Width....

Sill depth.

Lift per lock (varies).

Controlling bridge clearances:
Horizontal.

Vertical.

Aerial view looking upstream over the Bertrand H. Snell lock, showing the first two vessels to transit upbound through the new U.S. Seaway facilities. These are the Humberdoc, carrying newsprint to Milwaukee and Chicago and the Manitoulin, carrying pulpwood to the Welland Canal, July 4, 1958.