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Mersey Approach training banks
eastern end of the system, north of Perch Rock, New Brighton, Merseyside
associated engineer
Anthony George Lyster
date  April 1909 - November 1910, various dates to 1960
era  Modern  |  category  Walls/Abutments/Cuttings  |  reference  SJ305950
ICE reference number  HEW 1656
To improve access to Liverpool's Mersey Docks, a system of training banks was constructed in stages, beginning in 1909 and continuing right up to 1960. The sides of the natural sandbanks in the Mersey estuary were stabilised with dumped stone to direct the flow of the river as it enters Liverpool Bay, and prevent erosion.
To allow ships with bigger drafts to enter Mersey Docks, the Mersey Bar was dredged in 1896. This led to an increase in the velocity of water flow from the river estuary into the approach channel. A secondary channel formed through the offshore Burbo Banks and another started to form in Taylor's Bank (west of Formby). The bend in the north end of Crosby Channel began to get sharper, and Queen's Channel became distorted by the forward movement of Askew Spit and Little Burbo Spit.
Sand pump dredgers were used to try to stop these complex changes but the situation worsened. The stabilisation of Taylor's Bank, to prevent the bend in Crosby Channel becoming too sharp to navigate, became a priority.
So the first of the training banks, or underwater walls, was Taylor's Revetment, which runs along Taylor's Bank, around the outer edge of the channel. It was begun at the east end in April 1909 and completed in November 1910, two and a half miles to the west. The sandbank is faced with piles of limestone dumped from vessels on the surface.
Many more training bank works were to follow. The upper part of the estuary almost dries out at low water and fills with the incoming tide to become a gigantic reservoir, some 78 sq km in surface area. This is combined with a high tidal range of over 10m. The movement of water is enormous and the system of training banks stabilise and deepen the Port of Liverpool's 19 km of sea approaches. The alignment of the banks is critical. Hydraulic modelling was undertaken in 1930 to determine the way forward.
Most of the banks are limestone, dumped by a fleet of hopper vessels able to carry 660 tonnes each. In the deepest water, the banks have base widths of about 60m and are 7.5m to 9m wide at the tops. In shallower water, the crest widths are reduced to 4.5m and the banks have nominal side slopes of 2:1.
The works were all designed and built by the Mersey Docks & Harbour Board, whose Engineers during the period were ...
1897-1913 Anthony George Lyster
1913-1928 Thomas Monk Newell
1928-1941 Thomas Lord Norfolk
1941-1949 Leopold Leighton
1949-1958 Adrian Benson Porter
1958-1960 John Donaldson Jameson Saner
Research: PD
bibliography
"Engineering works for the improvement of the estuary of the Mersey"
by J.A. Cashin, Journal of the Institution of Civil Engineers, May 1949
"Field and model investigation into reasons for siltation in the Mersey estuary"
by Price and Kendrick
Proceedings of the Institution of Civil Engineers, April 1963
"Western Gateway" by A.S. Mountfield
Liverpool University Press, 1965
"Mersey Estuary and Approach Channels" by R.N. Norfolk
Transactions Liverpool Nautical Research Society, 1987
reference sources   CEH North
Location

Mersey Approach training banks