Ordnance Survey - 20th Century

20th Century

During the First World War, Ordnance Survey was involved in preparing maps of France and Belgium for its own use, and many more maps were created during World War II, including:

• 1:40000 scale map of Antwerp, Belgium
• 1:100000 scale map of Brussels, Belgium
• 1:5000000 scale map of South Africa
• 1:250000 scale map of Italy
• 1:50000 scale map of Northeast France
• 1:30000 scale map of the Netherlands with manuscript outline of German Army occupation districts.

After the war, Colonel Charles Close, then Director General, developed a marketing strategy using covers designed by Ellis Martin to increase sales in the leisure market. In 1920 O. G. S. Crawford was appointed Archaeology Officer and played a prominent role in developing the use of aerial photography to deepen understanding of archaeology.

In 1935, the Davidson Committee was established to review Ordnance Survey's future. The new Director General, Major-General Malcolm MacLeod, started the retriangulation of Great Britain, an immense task involving erecting concrete triangulation pillars (trig points) on prominent hilltops (some being difficult to reach) throughout Great Britain. These were intended to be infallibly constant positions for the theodolites during the many angle measurements, which were each repeated no fewer than 32 times.

The Davidson Committee's final report set Ordnance Survey on course for the twentieth century. The national grid reference system was launched, with the metre as its unit of measurement. A 1:25000 scale series was introduced, experimentally at first. The one-inch maps remained for almost forty years until the 1970s before being superseded by the 1:50000 scale series, as proposed by William Roy more than two centuries earlier.

Ordnance Survey had outgrown its site in the centre of Southampton (made worse by the bomb damage of the Second World War). The bombing during the Blitz devastated Southampton in November 1940 and destroyed most of Ordnance Survey's city centre offices. Staff were dispersed to other buildings, and to temporary accommodation at Chessington and Esher, Surrey, where they produced 1:25000 scale maps of France, Italy, Germany and most of the rest of Europe in preparation for the invasion of Europe. Ordnance Survey largely remained at its Southampton city centre HQ and temporary buildings nearby in the Southampton suburb of Maybush until 1969, when a new purpose-built headquarters was opened in Maybush adjacent to the wartime temporary buildings there. Some of the remaining buildings of the original Southampton city-centre site are now used as part of the court complex.

The then-new head office building was designed by the Ministry of Public Buildings and Works (MPBW) for 4000 staff, including many new recruits that were taken on in the late 1960s and early 70s as draughtsmen and surveyors. The buildings originally contained factory floor space for photographic processes such as Heliozincography and printing of maps, as well as large buildings for storing flat maps. Above the industrial areas are extensive office areas. The complex is notable for its concrete mural by sculptor Keith McCarter and the concrete elliptical paraboloid shell roof over the staff restaurant building.

In 1995, Ordnance Survey digitised the last of about 230,000 maps, making the United Kingdom the first country in the world to complete a programme of large-scale electronic mapping. In 1999 Ordnance Survey was designated a Trading Fund, required to cover its costs by charging for its products and remit a proportion of its profits to the Treasury. Officially, it is now a civilian organisation with executive agency status.

By the late 1990s, the need for vast areas for storing maps and for making printing plates by hand had been made obsolete by technological developments. Although there was a small computer section at Ordnance Survey in the 1960s, the digitising programme had replaced the need for printing large-scale maps while computer-to-plate technology in the form of a single CTP machine had also made obsolete the photographic platemaking areas. Part of the latter was converted into a new conference centre in 2000, which was used for both internal events and made available for external organisations to hire.

In summer 2010, the announcement was made that printing and warehouse operations were to be outsourced, ending over 200 years of in-house printing. As already stated, large-scale maps were not printed at Ordnance Survey since the common availability of geographical information systems (GIS), but until late 2010, the OS Explorer Map and OS Landranger Map leisure products were printed in Maybush.

In April 2009 construction began on a new head office located at Adanac Park on the outskirts of Southampton.

As of 10 Feb 2011, virtually all staff had relocated to the new building 'Explorer House' and the old site was sold off and redeveloped. Prince Philip, Duke of Edinburgh officially opened the new headquarters building on 4 October 2011.