Surveying the Glendoe Hydro Scheme

We recently caught up with two of our Inverness surveyors to find out what challenges they face in their remote corner of Scotland. They mentioned mapping the changes at a hydro scheme and I thought it might be an idea to find out how we updated our OS MasterMap database to show the Glendoe Hydro Scheme, Scotland’s largest recent civil engineering project. Craig and Dave faced a technical challenge in finding the best way to map the new and changed topographical features.


The Glendoe Hydro Scheme is located in the hills above Loch Ness near Fort Augustus and although a significant part of the project is underground, many new and changed features needed to be incorporated into our OS MasterMap database. These included the dam wall, the reservoir, all of the access and service roads, changes to water courses and their associated walls and sluices, and changes to the extents of vegetation and other surface features.


Glendoe as shown in OS OpenData

Glendoe as shown in OS OpenData


The area was originally surveyed using photogrammetry and then published at a scale of 1:10000. Peter Todd, Senior Production Manager at Ordnance Survey said, “Photogrammetry would be the normal approach to revising a large area of change in a remote location, but our surveyors chose to work on the ground for a number of reasons: the development was classified as a prestige site so we needed to update our data before the official opening with Queen Elizabeth II; with unpredictable weather in the area we couldn’t guarantee we could fly over and take the imagery in time; and the reservoir would not be filled with water until just before the opening, so we would need to survey the edge of the water by ground methods anyway.” Read More


Maps – the weird, wacky and wonderful

We all know that maps are pretty useful things. A weekend adventure in the Lake District, the sat nav in your car and many of our public services all rely on using maps or Geographic Information (GI). Just a couple of weeks ago I wrote about how Cardiff City Council is using GI to save a healthy £1.3m by reorganising their bus routes.

But the other day I started thinking about some more unusual uses for maps – the wacky, the bizarre or the inspired. And I was reminded of someone who loved maps so much they had wallpapered their toilet with them! I’m sorry to say we can’t find any trace of them or their toilet (if that person was you, get in touch!) but it prompted me to ask ‘what are the most unusual uses for maps?’

So, we put the question to our wonderful twitter followers who came up with these fantastic examples of map decor and clothes. Can you think of any others?

Maps as clothes

This fetching OS Landranger Map shirt is modelled by Alan Parkinson, also known as @GeoBlogs

Alan Parkinson

Alan Parkinson

Our own example comes in the form of the now (in)famous OS MasterMap jacket and tie!

5,000 changes a day are not made to this jacket

5,000 changes a day are not made to this jacket

Maps as wallpaper

We might not have been able to track down the person who papered their toilet with mapping, but Damian Watson showed us his lovely study, expertly wallpapered by his wife!

The south east of England has never looked better

The south east of England has never looked better

Maps as lamps

Maps do a great job in illuminating the landscape, now they can light up a room too! I’ll get my coat… Great work by ArtShades.

Handmade lamps courtesy of ArtShades

Handmade lamps courtesy of ArtShades

And finally, maps as art

The best maps are works of art in their own right, but Rita Donugh has taken this a step forward with this beautiful creation. Thanks to @Artythings for pointing this out to us.

Ordanance Survey, Birmingham By Rita Donagh

Ordanance Survey, Birmingham By Rita Donagh

So what else have you got?!


Mission:Explore – a GeoVating success

Yesterday evening I had the privilege to accompany the GeoVation team to London to celebrate the launch of the Mission:Explore iPhone app.

Incidentally, if you haven’t downloaded it yet, do it now!

Mission:Explore were one of our original GeoVation winners and the launch of the free app represents a fantastic outcome. With 1,000 missions to complete, it helps teach children that geography goes beyond measuring contour lines and grid references.

Don’t forget if you’ve got a geography based idea and could use a slice of £25,000, you should enter this year’s awards!

The event was held on the Golden Hinde and as such had a distinctly piratey theme! Much fun was had but there was the chance to meet some very interesting people who were keen to get involved as this year’s GeoVation Challenge continues to take shape.

If you want to know more about the app, here’s a film I took of the Mission:Explore team on a recent visit to Ordnance Survey.


Vernacular geography: What’s in a name?

There has been a bit of media coverage around in the last couple of week about some research we’re supporting at Cardiff University. It’s called Peoples’ Place Names, and they’re studying what’s known as Vernacular Geography.

What I might think of as the East End of London, or Shirley in Southampton, might be completely different from the next person, or at least different in ways I don’t realise. And that can still be the case even when a place has official boundaries.

For people that live or work in these places, the boundaries are often a matter of strong and passionate opinion. Have you ever met someone who, upon selling their house, was adamant that they didn’t live in a particular part of town?


Our sense of place can sometimes divide opinion. Image from Tim Green aka atoach via Flikr

And if you’re feeling really brave, why not start a debate about the exact location of The Black Country in the West Midlands? A lesson we learnt last year when we started printing the area on our OS Landranger Maps!

But in all seriousness, collecting these informal, vernacular place names could be really important in helping us build better place name gazetteers. These are not only important tools for us as map makers but also for the other organisations that rely on them, like the emergency services when responding to an incident.

When a 999 call comes in, knowing that King George’s Park is locally know as King’s Park or even “The Rec” could save vital minutes.

Last week in the Western Mail, Chris Jones, professor of geographical information systems at Cardiff University’s School of Computer Science and Informatics, said the data would also be very useful for online searching.

Last year we put The Black Country on the map, but steered clear of defining it's boundaries.

Last year we put The Black Country on the map, but steered clear of defining it’s boundaries.

He said: “Our language about space tends to be rather vague – lots of the way we refer to the world around us is vague.

“The idea of the site is to get people to tell us what names they associate with a particular place they live and give us postcodes and point to it on a map.”


A history of the OS Landranger map

The OS Landranger map is well loved by all outdoor enthusiasts. Its history, as the leisure map to use for planning days out and activities extends back many years and several generations have relied upon on ‘the pink map’ for their active pursuits.

OS Landranger - Barrow in Furness

OS Landranger – Barrow in Furness

The following describes the background and series specification of this famous Ordnance Survey map, from the early days, through metrification to today.

The history of the OS Landranger map goes back to 1791 when a One-Inch military map of the County of Kent was commenced. Published in 1801, the map of Kent was followed by a map of the County of Essex in 1803. The remainder of England and Wales, including the Isle of Man was completed by 1873; Scotland was completed in 1887. These sheets were printed in monochrome only, with coloured editions being started in the late 1800’s.

These were followed by a number of series with different formats and specifications. In 1945 the New Popular Sixth Series was started, each sheet covering an area of 40 x 45 km and incorporating the National Grid.

A Seventh Series was authorised in 1947 with the first sheets being published in 1952. These sheets were printed in ten colours but in 1962, for economic reasons, the number of colours was reduced to six. The Seventh Series comprised 189 sheets.

Metrication of Ordnance Survey map series to meet the Government metrication programme was introduced in 1965 and necessitated replacing the One Inch Seventh Series. Consultations with map users plus technical and economic factors resulted in the scale of 1:50 000 being chosen.

It was not possible to produce a completely redrawn series in the desired time scale so an interim 1:50 000 First Series was produced. The Series was compiled from photographic enlargements of One Inch Seventh Series material, assembled into a 40 x 40 km format, partially revised and printed in 6 colours.

The 1:50 000 First Series of 204 sheets was published in two blocks, the southern half of the country in 1974 and the northern half in 1976.
The conversion of First Series sheets to Second Series began in 1974 and was completed in 1987. Additions included metric contours as well as tourist and Forestry Commission information.

The early Second Series sheets were printed in six flat colours but later produced from a range of four process colours, black, cyan, magenta and yellow.

In 1980, tree symbols, depiction of foreshore categories and grid numbers on the body of the map were included in the specification. At the same time the name Landranger was adopted for the series.

The need for automation of production was recognised from a study in 1991 and a project was initiated in 1993 to establish requirements for maintaining the integrity and quality standards of the Second Series.

Following a production trial in 1994 on Sheet 95 that evaluated production methodology, performance results and flowline implications, the decision was made to proceed with conversion of all Landranger sheets to data format.’

And so, the OS Landranger we use today was born. This series covers the whole of Great Britain in 204 maps and provides all the detailed information you need to get to know an area.

If you’d like to browse the full series of OS Landranger maps or find out more, you can visit our map shop.


Wessex Archaeology – mapping the past

You might have read my blog on Wessex Archaeology’s finds at our new head office, describing the Bronze Age Farm that was once on our Southampton site…while chatting with the team, based on the outskirts of Salisbury, I discovered just how much they rely on our data, both on paper and in numerous electronic formats. Talking to Paul Cripps, Geomatics Manager at Wessex Archaeology (WA), I discover that their mapping interests run from historic mapping to OS OpenData and a whole range in between.

Much of WA’s work is spatial, finding out how things relate to each other. From historic buildings to excavations to the marine environment, mapping is fundamental to everything WA do. But they don’t just use it as a backdrop, they add information about their excavations and finds too and attach that to their mapping. I was surprised to find that the historic mapping is not only needed to understand change through time but to ensure the accurate interpretation of aerial photography amongst other things; it is not always easy to work out what is shown in an aerial photograph alone and the feature may not be shown on more modern maps, a second world war bunker on a disused airfield can look very similar to a Roman fort from the air!

Paul explained to me how surveying techniques have changed over the years, “OS Net changed the way WA worked. We’ve gone from using measuring tapes to mark out the locations of digs, to using total stations (tied in to trig points) to using differential GPS units (which had to be set up 4-5 hours before work could start). SmartNet uses the mobile phone network and it only takes 5-10 minutes for us to start surveying and we capture 95% of all work with our Leica SmartNet devices. We still use total stations to survey areas where 3D recording is needed, such as buildings and structures, skeletons in graves and so on, but trenches and all basic features can be accurately captured using SmartNet.

“A lot of people wonder what we’re recording all the time, but initial digging on a site only covers a percentage of the area and you need to accurately map these locations. Basic info can be added onto the GPS unit as you work, then we process it in AutoCad or ArcGIS, attach our full database records to the surveyed features, add modern and historic mapping and have all the information we need in one spatial environment.”

WA have six SmartNet systems and want to invest in more as being able to do everything on site makes life much faster and efficient. Rather than a survey team driving around the country and setting surveys up, now the GPS systems are so simple that archaeologists can do the majority of work themselves after some basic training. This leaves WA’s survey specialists to work on training and standards (and still do some surveying too!).

There are some great examples of WA surveying on their website and loads more pictures of them in action on Flickr too.


Exploring our surveying antiques

The prospect of the upcoming move to our new head office has resulted in buzz of increased activity around the building in recent months. Just like when you move house, it’s been a good time to have a bit of a clear out and take stock of what’s been hiding under the proverbial bed or in the attic.

Well, part of that process has included cataloguing the many pieces of antique surveying equipment that have been accrued by Ordnance Survey over the past 200 years. Some of the items have played an historic role in the birth of modern map making in Britain and are irreplaceable.

To understand more about some of this fascinating equipment, I caught up with Ken Lacey, a surveyor by trade who now works in our education team. Ken was kind enough to give me a tour of what is rapidly turning into an Aladdin’s cave of cartographic memorabilia, with two pieces being of particular interest.

Here’s what Ken told me:

Ramsden 18” Theodolite

This beautiful piece of kit was made by Jesse Ramsden and bought by Ordnance Survey in 1795.

It is made to the same pattern as the two larger 36” theodolites, also made by Ramsden, and used for the construction of the Principal Triangulation, the very first national triangulation programme to cover the whole of Great Britain which began in 1791.

The 18" Ramsden Theodolite

The 18″ Ramsden Theodolite

The 18 inches refers to the diameter of the horizontal measuring circle. This circle is where you can read the angle between two points of interest. To read this angle you need to view graduated marks through 3 microscopes.

It was used in 1826 for obtaining the precise direction of the Lough Foyle base line, and from that time at Principle Triangulation stations throughout the British Isles.

This famously included on a platform over the top of the cross on St Paul’s Cathedral in 1849. When you consider that its dimensions are 540x720x550mm and it weights 28kg that is no mean feat!

Newlyn Tide Gauge

Ever wondered how we can give a height of an object above sea level? Think about it, the sea is rising and falling throughout the day, year by year and at certain times of the months and seasons we get a higher tide or a lower tidal point.

To calculate Mean Sea Level Ordnance Survey needed to record all instances over the full range of possible variations. That required at least one year of observations for a reasonable determination, but in practise it was calculated over a number of years. From these observations it was then possible to establish the point of mean sea level and from that then calculate the difference in height from this point to any other fixed location.

The Newlyn Tide Gauge

The Newlyn Tide Gauge

To take all the readings required to calculate Mean Sea Level, you needed a tide gauge. Examples were set up Felixstowe (1913), Newlyn in Cornwall (1915) and Dunbar (1917). Subsequently it was decided to solely rely on the tide gauge at Newlyn, which is the one we’ve got here in Southampton, stored out of use.

It was chosen over the others because it was situated in an area of stable granite rock and because the gauge was perched on the end of a stone pier at the harbour entrance it was exposed to the open Atlantic.

It was not therefore liable to be influenced by the silting up of the estuary or river tide delays, as was the case at the previous gauge at Liverpool.

It worked by recording the rise and fall of the sea with two floats attached by chains. The variations were recorded on paper attached to the rotating drum suspended from its centre.

One of the floats that was attached to the bottom of the gauge

One of the floats that was attached to the bottom of the gauge

Every height measurement in the country has been calculated based on the work of this machine.

Responsibility for the Newlyn Tide Gauge continued to rest with Ordnance Survey who provided a full time observer until 1983 when the station was handed over to the Institute of Oceanographic Sciences.

Why not check out some of our other stories from behind the scenes?