Summary

An underground reservoir with a capacity of 413,000 gallons, built in 1824 for the Cheltenham Water Works Company to designs by James Walker (1781–1862), civil engineer of Limehouse.

Description

An underground reservoir with a capacity of 413,000 gallons, built in 1824 for the Cheltenham Water Works Company to designs by James Walker (1781–1862), civil engineer of Limehouse.

MATERIALS
Reservoir built in limestone, with brick roofing. Portal is in rubble stone with limestone ashlar dressings, and wrought-iron railings.

DESCRIPTION
The reservoir is entirely contained underground, but is entered by an above-ground portal, built into the higher ground to the rear. The portal is circa 2.5m high, and consists of an entrance bay with square top, central entrance doorway with a flat limestone lintel over, and limestone ashlar quoins. The portal is flanked by curving ashlar walls which sweep downwards and forward to meet the ground; these walls are topped by spear-headed railings, which continue to either side.

The underground reservoir measures 25.6m square overall, and the internal height is 4.3m; its capacity was 413,000 gallons (1.878 Ml). The structure consists of four parallel rectangular chambers with walls of limestone masonry, inverted-arched masonry floors, and brick jack-arched roofs. Four arched openings in the stonework of each of the internal walls allow water to flow between the chambers.

History

Cheltenham, and its suburb Charlton Kings, were expanding rapidly in the early years of the C19, and by the 1820s, the water supply was becoming inadequate. The response was the setting up of the Cheltenham Water Works Company, by Act of Parliament, in 1824. The company purchased a five-acre site set high on a hillside in Charlton Kings, off Hewlett’s Road (now Harp Hill), on which to build its new works. The site, which would collect water from the Northfield Springs on the surrounding hillsides, was selected as it was sufficiently high to allow the water supply to be fed to the town by gravity, rather than requiring pumping. The first underground reservoir on the site, with a capacity of 413,000 gallons, built in stone and designed by James Walker of Limehouse, was built in 1824, along with a custodian’s house, and supplied with a showy entrance with gates and gatepiers incorporating the Company’s crest. Water was carried through two miles of cast-iron pipes from the reservoir to the High Street in Cheltenham. The site was enlarged following a further Act of Parliament, and a second underground reservoir was added in 1839, also designed by James Walker; this brick-built reservoir was much larger than the first, with a capacity of 2 million gallons. Despite this, issues continued with the inconsistency of supply during the summer months, and in 1847, Henry Dangerfield, the County Surveyor, designed a new, open brick reservoir which covered three acres at Hewlett’s, holding 9 million gallons, which were drawn from more reliable springs further afield. Expansion of the complex, which was provided with a consistent boundary wall enclosing the entire site, was completed in 1857, with a still larger, fourth, open reservoir, this one with lobed brick walls.

No. 1 Reservoir, the first to be constructed on the site, was for much of its working life used to store spring water from the surrounding hills even after the site began to store water from other sources, specifically for use in brewing, as it was prized for its purity.

The Hewlett’s Reservoir site remains in use, now storing water extracted from the River Severn at the Mythe Pumping Station at Tewkesbury, though No.1 reservoir is now redundant. A concrete cover on piers was added to No.3 reservoir in 1966, after it was found that the pre-treated water it held was deteriorating in the open. No.4 reservoir was abandoned in 1965, and demolished in the 1990s. The custodian’s house was altered and extended in the later C20.

Reasons for Listing

No. 1 Reservoir at Hewlett’s Reservoir, an underground reservoir built in 1824, is listed at Grade II, for the following principal reasons:
* Technological interest: the reservoir is the earliest surviving example of an underground reservoir so far identified, and was designed by James Walker (1781-1862), one of the most distinguished civil engineers of the C19;
* Architectural interest: the chambers are constructed largely in stone rather than the more common brick, and the reservoir has a good above-ground portal with sweeping flanks;
* Intactness: the reservoir remains largely unaltered since its completion;
* Group value: as an important component in this early reservoir complex, forming part of a good group of buildings, which also includes No.2 Reservoir, the gates, piers and boundary walls, and the pavilion, all listed at Grade II.

External Links

• Historic England Listing
• Wikidata Q26677029

External links are from the relevant listing authority and, where applicable, Wikidata. Wikidata IDs may be related buildings as well as this specific building. If you want to add or update a link, you will need to do so by editing the Wikidata entry.

Recommended Books

• 
  Historic Environment Law: Planning, Listed Buildings, Monuments, Conservation Areas and Objects, Supplement 2014
• 
  Development and Design of Heritage Sensitive Sites: Strategies for Listed Buildings and Conservation Areas
• 
  Pevsner's Architectural Glossary (Pevsner Architectural Guides: Introductions)
• 
  The green guide for historic buildings: how to improve the environmental performance of listed and historic buildings
• 
  Hertfordshire (Pevsner Architectural Guides: Buildings of England)
• 
  Oxfordshire: North and West (Pevsner Architectural Guides: Buildings of England)