Reasons for Designation
One Tree Hill Conduit Head is designated at Grade II for the following principal reasons:
* It is a late C17 or early C18 conduit head in the Classical style possibly designed by Nicholas Hawksmoor, Clerk of the Works at Greenwich between 1698 and 1735. It is unaltered apart from the later blocking of the central arch when the conduit system became obsolete.
* It is of a different design but more elaborate than a conduit house from the same system in Hyde Vale, Greenwich, already listed at Grade II.
* Conduit heads or houses are a rare building type nationally; only 33 examples are currently listed in England.
* It is part of a group of related structures which were part of the earliest water supply for the Royal Hospital of Seamen, now The National Maritime Museum (Grade I).
Details
786/0/10196 MAZE HILL
25-SEP-09 Greenwich Park
Conduit Head at One Tree Hill,
Greenwich Park
II
Conduit head at One Tree Hill. Late C17 or early C18, possibly designed by Nicholas Hawksmoor who was Clerk of the Works at Greenwich from 1698-1735. Classical style. Built of yellow and red brick with some stone dressings.
PLAN: A semi-circular shaped brick and stone wall set in sloping ground, originally the entrance to a conduit running north to south under One Tree Hill but now blocked.
EXTERIOR: It comprises a central block, flanked by curving arms which slope downwards to ground level. The central block is 2.2m high and 2.2m wide. It is constructed of yellow brick in Flemish bond but with some red brick quoins and arch voussoirs. There is a central round-headed arch 1.35m high and 0.75m wide with a stone keystone and three other stone quoins. A stone band incorporates the keystone and there is a flat stone coping. A stone plaque above the arch has an inscription which is now illegible. The arched opening was blocked in red brick in header bond in the 1980s or 1990s with reused bricks. The arms are of yellow brick in Flemish bond and are butt-jointed to the central block suggesting they are later additions but still C18. They have a C20 concrete coping. Alongside the stone coping the curved brick roof of the conduit can be glimpsed, although the conduit is now inaccessible. In 1902 it was recorded that a branch ran eastwards in the direction of Maze Hill.
INTERIOR: The entrance has been blocked in brick and there is no access. The conduits beneath are not included in the listing.
HISTORY: At least three underground tunnels or conduits are known to exist under Greenwich Park, brick-built and practically large enough in which to walk upright. These were water mains designed to channel natural groundwater from higher up the hill down to the buildings of the Royal Hospital for Seamen (now the National Maritime Museum) in Greenwich, a Grade I listed building. The building of the Royal Hospital was commenced in the reign of King William and Queen Mary in 1696 (utilising an uncompleted building of 1664 originally designed to be a palace) to the design of Sir Christopher Wren. The hospital opened in 1705, although it was not completed until much later in the century. Pevsner's "Buildings of England" considers that Nicholas Hawksmoor, Wren's pupil, had special responsibility for conduits. In 1698 he became Clerk of Works at Greenwich, retaining this post until 1735, and was Deputy Surveyor there between 1705 and 1729. Although the surviving conduits were rebuilt at the end of the C17, earlier conduits for the Tudor palace or even medieval manor houses may have been reused by the Naval engineers. Lead pipes carried the water to reservoirs at the end of the conduit systems. The C18 and C19 saw a decline in the conduit system and several were abandoned as early as 1732. In 1831 a report argued the need for an improved water supply for the Royal Hospital by the creation of reservoirs and the replacement of the existing lead pipes with iron. In 1845 a new reservoir was built in Greenwich Park by Great Cross Avenue. In 1905 and 1906 Greenwich Borough Council inspected these conduit structures and made reports. After this, known entrances to the conduits were sealed by the Royal Parks authority to prevent unauthorised access. There are three known conduit heads or houses which served the Royal Hospital for Seamen, one at Hyde Vale, the Conduit House at Standard Reservoir and the One Tree Hill Conduit Head, all listed.
SOURCES:
N Pevsner and B Cherry, "The Buildings of England. London 2: South", 1994. p265.
RCHME: 'Greenwich Park Archaeological Survey. Part I', March 1994. pp13-15. p38.
Dictionary of National Biography entry for Nicholas Hawksmoor.
Museum of London Archaeology Service, 'London Olympics Equestrian Centre, Maritime World Heritage Site, archaeological desk-based assessment', 2008.
AD Webster, "Greenwich Park, its history and associations", 1902.
REASONS FOR DESIGNATION:
The One Tree Hill Conduit Head is designated at Grade II for the following principal reasons:
* It is a late C17 or early C18 conduit head in the Classical style, possibly designed by the architect Nicholas Hawksmoor, Clerk of Works at Greenwich between 1698 and 1735. It is unaltered except for the blocking of the entrance arch.
* Conduit heads or houses are a rare building type nationally.
* It is part of a group of related structures which were part of the earliest water supply for the Royal Hospital for Seamen, opened in 1705, now the National Maritime Museum (Grade I).
