Post by Administrator on Jul 18, 2021 12:46:28 GMT
The Lady Windsor Lock.
Dock basin.
The original entrance to the docks is 80 feet (24 m) wide, with two wrought-iron gates operated by direct-acting hydraulic cylinders. This sea entrance leads into the Basin, (rarely called No.3 dock), that is 600 by 500 feet (180 by 150 m) and covers 7 acres (2.8 ha).
At its northwest end, the Basin is connected to No.1 dock by an 80 feet (24 m) wide passage with another pair of wrought-iron lock gates, so that when required, the Basin can act as a lock, with the water level adjusted according to the rising tide, so wide-beamed vessels can leave the basin before high water and can enter the basin after high water.
In its twilight years of vessel movements, the Basin sea locks were only used for vessels of 'above normal' beam as unlike the Lady Windsor lock width of 65 feet, and opened on 4 January 1898, to the west of the Basin, the Basin entrance was 80 feet wide as was its northwest lock channel to & from No.1 dock. The walls of the basin are vertical apart from a sharply curved batter at the base, which makes the toe very strong. The foundations are solid and the backfill is high quality so that the pressure on the walls is minimised.
The walls are built of mountain limestone faced with hard red sandstone and rest on solid rock. They are 50 feet (15 m) high, 17 feet (5.2 m) thick at the base just above the curve, and 7 feet (2.1 m) thick at the top.
The Basin gates contain many sluices, so water can be quickly drained out or let in according to whether the sea level is above or below the prevailing docks water level. However, more water is lost from No.1 dock supply if the Basin water is lowered to the seaward side of the lock gates instead of using the Lady Windsor lock sluices. In the early days, the dock operators would often run the water down to bring in a single ship having a wider beam than the Lady Windsor lock could handle.
At first, the docks were only accessible via the Basin for a few hours during high water. While waiting, ships could anchor to the east of the docks between Barry Island and Sully Island.
The Lady Windsor Lock, opened on 4 January 1898, was named after the wife of the chairman of the company. It is 647 by 65 feet (197 by 20 m) and opens into the sea to the west of the Basin.
The lock is 60 feet (18 m) deep. It could be divided into two locks, using a gate about one-third of the way from the sea entrance.
In its day, the Lady Windsor lock was said to be the largest and deepest lock in the world.Vessels that draw 13 feet (4.0 m) can enter and leave the dock at low water during ordinary spring tides. Vessels that draw 18 feet (5.5 m) can enter at low water 15 days per month.As of 1924, the channel leading to the lock was dredged to 13 feet (4.0 m).
Ships generally use Lady Windsor Lock, whilst the Basin serves as an alternative for large-beamed vessels or in cases where the Lady Windsor lock gates are being repaired.