Portsmouth Dockyard: dockyard basin and six surrounding dry docks, as well as sections of sea wall and a network of culverts

Summary

Dockyard basin and six surrounding dry docks, as well as sections of sea wall and a network of culverts. The basin and some of the docks are of late-seventeenth century origins. The current structures largely date to between the mid-eighteenth and early nineteenth centuries. The monument falls partially over the site of the earlier docks dating from the fifteenth century.

Reasons for Designation

The monument, Number 1 Basin, and the surrounding number 1 to 6 Docks, as well as sections of sea wall and a network of culverts, Portsmouth Dockyard, is scheduled for the following principal reasons:

* Period: the historic core of the pioneering Portsmouth Dockyards, the country's longest operating Royal Naval Dockyard and site of the world's first dry dock. It possesses evidence of major developments in dockyard engineering, including the employment of Bentham’s pioneering inverted arch construction method, with what is believed to be the first example evident at the entrance to the basin, where it was built in conjunction with Smeaton’s innovative waterproof hydraulic lime mortar. Key development phases of the current dockyard structures include the building works dating to the late C17 under Dummer and the late C18 to early C19 under Bentham;

* Survival: the ensemble of dry docks and the basin—together with their associated culvert network and surviving sections of sea wall—retains an excellent degree of integrity. These structures collectively continue to illustrate the enduring legacy of England’s naval engineering and maritime infrastructure. Portsmouth was also the site of one of the first terraced stone docks in the country in the 1690s (site of Number 5 Dock), as well as the site of the first use internationally of the influential timber caisson design;

* Documentation: the site benefits from a good level of cartographic, archival, and archaeological documentation, providing detailed insight into its origin, evolution, and operational history;

* Potential: for its potential to provide further information about the construction of the late C18 and early C19 dock complex, as well as earlier phases of dock construction;

* Group value: holds strong group value with other structures within the wider Portsmouth Dockyard site, including the connected reservoir (formerly basin) beneath the Block Mills and Stores 35 and 36 (scheduled 1001851 and listed Grade I 1078288). The monument also has group value with the vessels located within the dry docks which appear on the National Register of Historic Vessels as part of the National Historic Fleet: HMS Victory (registration number 499), Mary Rose (registration number 1951) and HMS M33 (registration number 482).

History

The first dry dock in England was established within an 8-acre site at Portsmouth in the late C15 during the reign of Henry VII (approximately in the location of the current Numbers 1, 2 and 3 Docks and the south end of Number 1 Basin, extending to the south and east). In the early C16, under Henry VIII’s reign, the dockyard was enlarged by nine acres, fortified, and further developed; during this time, the flagship vessel, the Mary Rose, was constructed within the dockyard. The dockyard was further expanded during the First Dutch War, between 1652 and 1654, and again under Charles II’s reign, between 1665 and 1667. By 1688, the dockyard included a timber single dock, known as South Dock (precursor to Number 1 Dock), a timber double dock, and a slip.

A major rebuilding of the Portsmouth Dockyard was carried out between 1689 and 1698, during the reign of William (III) and Mary (II). The rebuilding was principally directed by naval engineer and shipbuilder Edward Dummer (1651–1713), who served as Surveyor of the Navy from 1692 to 1699. The first phase included the establishment of a square, non-tidal basin, the Great Ship Basin (Number 1 Basin), located to the north of the double dock. A dry dock, known as the Great Stone Dock (site of Number 5 Dock), was constructed on the east side of the basin. Along with Dummer’s contemporary dry dock at Plymouth, the Great Stone Dock was among the first in England to feature stepped stone sides, known as altars, instead of timber. The dock could be drained to allow access to a vessel’s hull via the broad altar walkway midway down the walls. Steps and chutes were included to facilitate the movement of material, goods and vessel repairs. Whilst the walls were constructed of stone, the dock floor continued to consist of wooden baulks laid horizontally on timber piles driven into the mud. A pair of mitre gates were installed at the entrance to the Great Stone Dock to provide additional resistance to water pressure. Dummer installed a tidal waterwheel and horse-gin pumping system to drain this dock; this system was not adopted more widely. Another dry dock, initially constructed in timber and known as Small Dock (precursor to Number 6 Dock), was established on the north side of the Great Basin. The dock connected the Portsmouth Harbour side to an additional non-tidal basin, which became known as the North Basin (site of the Block Mills).

Between 1737 and 1743, Small Dock (Number 6 Dock) was rebuilt in stone with stepped sides and a modified east end, cutting off the adjacent North Basin from the harbour; the dock was renamed North Stone Dock. Following the Seven Years’ War (1756–1763) between Britain and France, the dockyard was reorganised to improve efficiency. From the 1760s, a programme of improvements was undertaken, including the deepening of the Great Ship Basin (Number 1 Basin). The Great Stone Dock (Number 5 Dock) was extended to the east, changes were made to the entrance, the broad altar was redesigned, and further chutes and steps were added. The dock floor may also have been lowered at this time, although the timber floor was retained. By 1772, a new dry dock was added to the east of the basin, known as the Middle Dock (Number 4 Dock), replicating the form of the Great Stone Dock. Between 1771 and 1776, a sluice-gate system was replaced by a network of underground culverts to drain the docks more efficiently. The culverts linked the docks to a reservoir and pump house created within the repurposed former North Basin. By 1777, the North Stone Dock (Number 6 Dock) had undergone further modifications. The timber South Dock (site of Number 1 Dock) was also proposed for rebuilding as part of the 1760s modernisation; construction was delayed and did not begin until 1789.

In 1795, Brigadier General Sir Samuel Bentham (1757–1831) was appointed Inspector General of Navy Works. Between 1795 and 1803, Bentham supervised the continued modernisation of the dockyard and planned changes to the design and layout of the dry docks. The Great Ship Basin (Number 1 Basin) was enlarged and extended to the south over the site of the former double dock. The entrance to the basin was relocated to the centre of the west side of the new configuration. To overcome the inherent structural issues of dock construction, Bentham tied the new entrance gate piers together using an inverted masonry arch; this is thought to be the first use of this form in the history of dock construction. Bentham made pioneering use of waterproof cement (hydraulic lime) invented by John Smeaton and also installed a timber caisson (floating dam) at the entrance to replace the leaking sluice gate; this structure was the world’s first timber caisson (replaced in steel in C20). Work completed during Bentham’s tenure included the delayed rebuilding of South Dock (Number 1 Dock) in 1801. He oversaw the construction of two additional docks, Number 2 (completed 1802) and Number 3 (completed 1803) Docks, at the south-east corner of the basin. Number 3 Dock is widely regarded as the first dock to employ the inverted arch principle. Number 5 Dock's floor was also rebuilt using the inverted arch principle. Number 2 Dock, and possibly Number 1 Dock, also employ inverted arches; these are likely to be a subsequent mid-C19 intervention as part of a change to the dock floors. By 1807, the system of culverts, which had been extended to serve Bentham’s newly constructed Docks 1 to 3, was controlled by sliding copper-lined timber penstock doors; as part of Bentham’s improvements, the modified culverts was operated via a steam-powered pumping system.

In 1810, the bottom of Number 6 Dock was replaced with stone; it has been suggested that the rebuilding included the use of the inverted arch construction method. During the C19, Number 4, 5 and 6 Docks were covered by roofed structures, later removed. In the mid-C19, to facilitate the repair of larger vessels, some docks were remodelled, including the replacement of timber dock floors with stone and brick, and the lengthening of docks. In 1850, Number 5 Dock was lengthened, and later the timber gates were replaced with metal. In 1859, Number 4 Dock was enlarged to accommodate the wheels of paddle steamers; the gates were replaced by a caisson, the entrance and dock head were widened and squared off, and the floor was partially constructed in brick. During the latter half of the C19, the head of Number 1 Dock was extended using Portland cement and concrete.

The head of Number 5 Dock was extended and rebuilt in 1906. Soon after, the heads of Number 1 and 6 Docks were extended. With the development of the naval dockyard, including the establishment of the Great Steam Basin, the repair of larger vessels moved elsewhere within the wider dockyard. From the early C20, the historic basin and docks continued to be used for the repair of smaller vessels. In 1922, HMS Victory was installed within Number 2 Dock, after which a concrete dam was built adjacent to the site of the dock gates. During the inter-war period, the upper altar steps to Number 4 Dock were infilled to create vertical concrete sides. During the Second World War, the basin and surrounding docks were subject to three direct hits; Number 1 and Number 2 Docks suffered bomb damage and were subsequently repaired.

In 1997, HMS M33 (Minerva) was installed within Number 1 Dock. In 1982, the Mary Rose was installed within Number 3 Dock; it was housed in a temporary structure until 2013, when a new museum building was installed over the dock. During construction, archaeological investigations and watching briefs were undertaken in and around the dock, providing evidence for the dock’s construction. The remains of various phases of structures located adjacent to the dock were also identified, including sections of culverts, which may be additional to the known culvert network; their full extent is not currently known. Sections of stone steps and chutes along the sides of the Number 3 dock were removed to accommodate piles for the new museum; the work was carried out with Scheduled Monument Consent and subject to archaeological monitoring. All of the dock gates and caissons currently in position are replacement structures, most dating to the C20 with some C19 replacements. Some of the docks have also been enclosed by C20 cofferdams. During the C20 and C21, various phases of jetties have been built on the west side of the sea walls.

Details

PRINCIPAL ELEMENTS: dockyard basin and six surrounding dry docks, as well as sections of sea wall and a network of culverts. The basin and some of the docks are of late-C17 origins. The current structures, largely dating to between the mid-C18 and early C19, have been noted as one of the finest surviving examples in Europe (Coad, 1989, 97). The monument falls partially over the site of the earlier docks dating from the C15.

Most of the monument is also designated as a Grade I listed building (NHLE entry 1272267).

DESCRIPTION: from south to north, the site consists of Number 1 Dock, Number 1 Basin with Docks 2 to 5 along its east side, and Number 6 Dock to the north, with a surrounding network of culverts. To the west are sections of the masonry sea walls. The basin and most of the docks incorporate sets of inscribed Roman numerals that mark the datum level, usually aligned with the dock or basin sill.

Number 1 Basin

Number 1 Basin was first constructed under Dummer in the late C17, modified in the mid-C18; its current form largely relates to its enlargement between 1796 and 1801 under the direction of Bentham. It is roughly rectangular in plan and connected to Portsmouth Harbour on the western side. The basin walls are constructed of Portland stone with vertical tools and topped by granite coping. There have been several repairs in concrete and brick. including the replacement of some granite copings with in-situ concrete. The entrance to the basin is constructed of Portland stone and the sides are tied together by Bentham’s ‘inverted arch’; stone set within John Smeaton’s hydraulic lime mortar. The modern caisson at the entrance is in the position of Bentham's original timber caissons. On the basin’s west side, adjacent to the entrance, the stonework is engraved with ‘BRITANNIA JUNE 12, 1801’, to commemorate the docking of the first ship after Bentham’s expansion. In the north-east corner of the basin there is a culvert portal with dressed stone voussoirs over the arched entrance. There are iron fixings, including mooring rings, and some C19 fairleads are attached to the walls.

Number 1 Dock

Number 1 Dock was built between 1789 and 1801 on the site of a C17 timber dock. The dock is constructed of Portland stone blocks with granite coping. There are later repairs and additions which are principally constructed of concrete and cement. The western approach to the dock has been infilled, and the dry dock is no longer accessible from Portsmouth Harbour. The dock walls consist of terraced altar steps and include a broad altar at the midpoint. There is a symmetrical arrangement of stairs and chutes located around the side and running between the dockside, broad altar and dock floor. The dock head to the east, extended in the early C20, has vertical sides which are covered in a cement-based render. The south-eastern corner of the dock was damaged during a bombing raid in 1941; the steps at the level of the broad altar have been rebuilt using reinforced concrete with concrete coping. The dock floor comprises in-situ concrete slabs cast in cross-sections over the originally constructed timber dock floor. Iron mooring rings and some C19 fairleads are attached to the dock walls.

Number 2 Dock

Number 2 Dock was constructed between 1799 and 1802 and the first dry dock to be fully developed under Bentham, with Parlby and Rankin as contractors. The majority of the dock is built of Purbeck limestone, with Portland limestone in place at the north end; the walls have granite coping. It incorporates an inverted arch construction. The dock entrance retains curved walls which follow the profile of the original curved timber dock gates. The dock walls consist of terraced altar steps and include a broad altar. There is a symmetrical arrangement of stairs and chutes located around the sides, running between the dockside, the broad altar, and the dock floor. Most are stone, with one set of stairs being a later concrete construction. There are iron fixings including mooring rings attached to the walls. Repairs to the dock walls include incised concrete rendering following bomb damage during the Second World War. There are also various phases of stone replacement and mortar repairs dating from the late C20 to early C21. The south-east dock head has a square end which is partially bordered by a low retaining wall. The floor of the dock is constructed of in-situ concrete, which covers the original timber dock floor; sections of the timber floor remain visible. The dockside is surrounded by granite setts dating to C19 or earlier and incorporates C19 bollards and fairleads.

Number 3 Dock

Number 3 Dock was constructed between 1799 and 1803; designed by Bentham, it was the first dock to employ his ‘inverted arch’ technique, which extends along the length of the dock. It is constructed of Portland and Purbeck stone with granite coping. The dock walls consist of terraced altar steps, and include a broad altar which has been rebuilt using reinforced concrete. There is a symmetrical arrangement of stairs and chutes located around the sides, running between the dockside, the broad altar, and the dock floor. During the interwar period, the upper steps and chutes above the broad altar on the dock’s south side were infilled with concrete to create vertical sides. During the early C21 construction of the Mary Rose Museum, modifications were made to the dock structure, including some of the chutes and stairs. The stepped walls also include areas of concrete repair. There are iron fixings, including mooring rings, attached to the walls. The dock head to the east has a square profile. The dock floor consists of C20 in-situ concrete cast over the original timber flooring.

Number 4 Dock

Number 4 Dock was first constructed in 1772 and modified in 1859. The dock is constructed of Portland stone with granite coping. The lower dock walls are terraced altar steps, including a broad altar. The walls above the broad altar have been infilled with concrete coping to create vertical sides. There are stairs and chutes located around the sides, running along the broad altar and to the dock floor; above the broad altar most of the chutes and stairs have been infilled or capped with concrete. The head of the dock is stepped; the stonework is recessed at this end to accommodate a ship’s bow, and it is flanked by two sets of stone steps leading down to the altar. There are iron fixings including mooring rings attached to the walls. The floor has a central strip of granite setts flanked by brick paving and may date to the C18.

Number 5 Dock

Number 5 Dock was first built in the 1690s as one of the first terraced stone docks in the country; it was modified and extended to the east and west in 1769, with later alterations. The dock is constructed of Portland stone with granite coping. The original mitre gates have been replaced; however, the gate recesses are retained, indicating their curved profile. The entrance headwalls are constructed from Portland stone, with a narrowing collar of stepped stonework. The dock sides are mostly terraced with altar steps, including a broad altar. The north side of the dock, above the broad altar, has been infilled with concrete to create a vertical side. Along the north side of the dock are a series of metal plates supported by cantilever brackets. There are stairs and chutes located around the dock walls, running between the dock side, the broad altar, and the dock floor; those on the north side have been filled in above the broad altar. The head of the dock was lengthened in the early C20 and was modified using shuttered concrete. The dock floor has a C20 in-situ concrete finish, which has been cast over the inverted-arch construction. Iron fixings, including mooring rings, and some C19 fairleads are attached to the dock walls.

Number 6 Dock

Number 6 Dock was built between 1737 and 1743 on the site of a late-C17 dock, with modifications in the late C18, early C19 and early C20. The dock is constructed of Portland stone with granite coping. In 1997, boreholes placed through the dock wall confirmed that it was constructed of brickwork underlying the stone facework, and that the walls continue to be supported on a foundation made of timber platform piles. The entrance headwalls are constructed from Portland stone. The dock sides are terraced with altar steps, including a broad altar. The upper altars are more steeply profiled than the lower. There are stairs and chutes located around the sides, running down to the broad altar; additional intermediate steps are set on the altars, mostly C20 cast concrete, providing access to the dock floor. The head of the dock was altered in the early C20, has vertical sides, and is constructed in shuttered concrete. The bottom of the dock consists of in-situ concrete cast over the inverted-arch floor. Iron fixings, including mooring rings, and some C19 fairleads are attached to the dock walls.

Sections of Sea Walls

Sections of the dockyard’s sea walls run along the west side of the dock and basin. They were principally constructed in the late C18 to early C19 as part of Bentham’s dockyard extension and may incorporate the remains of Dummer’s earlier basin and dock walls. The walls are constructed of large blocks of Portland stone with granite coping (some C21 replacements). It is believed that the wall foundations stand on timber piles. There are various portals, holes and arched openings along the lower level of the wall, some of which contain metal grates. There are also C20 repairs in concrete and brick, as well as areas of cement mortar patching and in-situ concrete used to replace some of the granite copings. Sets of inscribed Roman numeral draught marks are present at various points along the length of the walls, and toward the south end, the upper level includes carved lettering: ‘HWOST’.

Culverts

A network of culverts, constructed in the late C18 and early C19, connect the dry docks and basin to the reservoir below the Block Mills (National Heritage List for England entry 1001851, Grade I list entry 1078288). The culverts are generally rectangular in sectional profile; however, the culvert attached to Number 6 Dock is vaulted. The culverts are principally lined with coursed Portland limestone masonry walls and floor slabs, with soffits formed of flat limestone slabs. There is some corbelling to the tops of the walls to support the slabs above. There are also some sections faced in brick with a curved arch roof. The dimensions of a typical culvert are approximately 900mm wide and 1600–1900mm high; the culvert attached to the north-west corner of the basin is wider. The stone-lined culvert portals, most with metal grates, are located around the base of the dock and basin walls; the portal to Number 3 Dock was blocked in the C21. The culverts are operated by copper-clad wooden penstock doors housed within shafts located at various points along their route; some of the doors have been replaced with steel doors. The shafts are accessed via metal ladders. Several shafts include associated below-ground winding gear, as well as metal drive shafts that extend above ground level; some of the drive shafts have been removed or replaced in the C20 and C21.

EXTENT OF SCHEDULING: the scheduling aims to protect the known extent of the basin and dock and their entrances, including walls, steps, chutes and floors. Number 2 Dock includes the well-preserved remains of the cobblestone granite setts that surrounds the dock. The scheduled area is also drawn to follow the course of sections of masonry sea walls on the west side of the dockyard, as well as the known extent of the culvert system associated with the docks and basin.

EXCLUSIONS: the C20 and C21 security fences and railings, metal access ladders, as well as mounted lifebuoy housing attached to the monument, including those that line the docks, basin, culvert shafts, and those located above the sea walls, are excluded from the scheduling. C20 and C21 services and associated infrastructure, including lights and cable, attached to the docks, basin, sea walls, and culverts are also excluded. All C20 and C21 signage attached to the docks and the C20 and C21 surfaces which cover some of the dock staircases and chutes are likewise excluded. The caissons, mitre gates and cofferdams associated with the docks and basin are all later replacements and for this reason are also excluded. However, the ground/dock structure below and attached to the above features is included within the scheduling.

The vessels HMS M33 and HMS Victory and their associated infrastructure, including C20 and C21 metal and concrete supports and stands on which the vessels rest, walkways, lifts, and staircases attached to and within Numbers 1 and 2 Docks, are excluded from the scheduling. The Mary Rose, its C21 museum building, and associated C20 and C21 infrastructure, including supports and stands on which the vessel rests, walkways and staircases within and above Number 3 Dock, as well as C20 and C21 surfaces above the largely covered dock walls, are likewise excluded. However, the ground/dock structure below and attached to the above features is included within the scheduling; this includes the concrete-covered dock floors.

The historic culvert system, apart from the access shafts, is an underground feature located below surface level; all furniture, buildings, and C20 and C21 structures and surfaces located above the underground culvert network are excluded from the scheduling. The removable wooden planks and metal plates that cover the culvert shaft openings are also excluded from the scheduling, although the shaft structures beneath are included. C20 and C21 replacement drive stafts and penstock doors are likewise excluded; but the shaft structure attached is included within the scheduling.

The C20 and C21 jetty structures which abut the sea walls are not included in the scheduling. The furniture, structures and C20 and C21 surfaces above the sea walls (not including replacement granite coping stones which top the walls) are excluded from the scheduling, although the sea wall structure they are attached to is included.

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

PO 397

Legacy System:

RSM - OCN

Sources

Books and journals
Coad, J G, The Royal Dockyards 1690-1850: Architecture and Engineering Works of the Sailing Navy, (1989)
Coad, J, Historic Architecture of H M Naval Base Portsmouth 1700-1850, (1981)
Coad, J, The Portsmouth Block Mills: Bentham, Brunel and the start of the Royal Navy’s Industrial Revolution, (2005)

Other
Castria, J22-068 | The Historic Naval Dockyard (1001852 & 1272267), HMNB Portsmouth Conservation Management Plan, December 2022
Pritchard Architecture, Quadrennial Inspection REV P1 Sea Wall, December 2024
Pritchard Architecture, Quadrennial Inspection REV P1 J16-028 Dock 1, December 2024
Pritchard Architecture, Quadrennial Inspection REV P1 J16-028 Dock 2, December 2024
Pritchard Architecture, Quadrennial Inspection REV P1 J16-028 Dock 3, December 2024
Pritchard Architecture, Quadrennial Inspection REV P1 J16-028 Dock 4, December 2024
Pritchard Architecture, Quadrennial Inspection REV P1 J16-028 Dock 5, December 2024
Pritchard Architecture, Quadrennial Inspection REV P1 J16-028 Dock 6, December 2024
Pritchard Architecture, Quadrennial Inspection REV P1 1-153 Reservoir and Culverts, December 2024
Pritchard Architecture, Quadrennial Inspection REV P1 J16-028 No 1 Basin, December 2024
WORK 14/3075, Portsmouth Dockyard: maps, held in the National Archives
WORK 41/335-336, H M Naval Dockyard, Portsmouth: Docks. Plans of part of dockyard: Signed by Samuel Bentham, held in the National Archives
ADM 140/589 – 603, Various plans, sections and drawings of Portsmouth Dockyard, held in the National Archives
MPEE 1/171, Hampshire, Portsmouth. Plan of proposed works for Portsmouth dockyard in 1863-1864, with notes on land claimed by the Corporation of Portsmouth and the Office of Woods. Shows named buildings and streets, docks, basins, inlets, tidal levels, held in the National Archives
WORK 41/361- 372, Various plans, sections and drawings of Portsmouth Dockyard, held in the National Archives
EAW023268 HMS Victory at Portsmouth Historic Dockyard and environs, Portsmouth, 1949 Aerial Photograph-Aerofilms, held in Historic England Archive
Pritchard Architecture, Basin No 1, Docks No 1 to 6 HMNB, Portsmouth: Heritage Statement, January 2023
Thornber R, Heritage Impact Assessment Scaffolding Starboard Side of HMS Victory, Portsmouth Historic Dockyard, Portsmouth, Hampshire, September 2020

End of official list entry

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