"Conserving Scotland's Civil Engineering Transport Heritage - a Personal Retrospect" by Professor Roland Paxton, Heriot-Watt University: Edinburgh meeting: 8 April 2014

As chairman of the ICE panel for Historical Engineering Works, Professor Roland Paxton works tirelessly to promote awareness of Scotland's engineering legacy.

He organised plaque-unveilings for the 250th anniversary of Telford's birth in 2007, and has similarly celebrated Scotland's greatest railway engineer John Miller. He reflected on how we may better appreciate structures ranging from the Forth Bridge to Berwickshire's Union Bridge that form a continuing part of our transport networks.

Scotland saw two transport manias, canal-building from 1790 and then the railways which by the 1840s had superseded them. Roads which had been improved by Telford and Wade then declined but revived with the dawning of the motor age after 1900.

The relative merits of these modes in the 1820s were that a horse could pull just 1-1.5 tons on the poor roads then existing but up to 10 tons on a railway and 100 tons on a canal.

In the 1960s when everything traditional was being swept away in the name of progress, the Institution of Civil Engineers formed the Panel for Historical Engineering Works to identify, record and promote knowledge of Britain's civil engineering heritage and encourage excellence in the conservation of its finest examples. PHEW set about meeting these aims by publications, direct involvement, correspondence, lectures, maintenance of records, advice, exhibitions, media interviews and visits. Other parts of Britain merited a single volume each, but the guide to Scotland's civil engineering heritage by Roland Paxton and the late Jim Shipway stretched to separate ones for the Highlands and Lowlands with on their respective covers the finest examples of great iron bridges at Craigellachie and across the Forth.

Roland Paxton had come to Scotland in 1964 on being recruited by city engineer Frank Dinnis to build Edinburgh's proposed inner ring road, but it was defeated by objectors and instead he got to build the Western Approach Road which by retaining the bridges and retaining walls of the old Caledonian Railway with just a carpet of tarmac on the ballast achieved a 49% rate of return and never was replaced by the planned M8 extension.

He was then able to persuade the police that without attracting glue-sniffers the tunnels of the old Innocent Railway could be turned into a popular cycle-path, and while far too late to save its onetime stationary engine was able to conserve an 1831 iron bridge across the Braid Burn which received a PHEW exceptional care award. At Glenesk the Greenbelt Trust removed an excrescence from the arch and he was able to show that it dated from 1829-31 : soon trains will again cross on the new Borders Railway. Bilston Glen towering 100 metres over a wooded gorge was saved by the Scottish Viaducts Committee, and Dinnis allowed Roland to open up Telford's Dean Bridge which is not allowed nowadays.

Telford's lighthouse at Dundee's floating harbour now stands in a park, the dock complex having long gone. In 1996 Roland paid the farmers on either bank of the River Irvine £1 each to acquire from them the world's oldest arch on a public railway at Laigh Milton, having persuaded both that the collapse seven years earlier of the Ness Bridge had shown that the value of the stone could be outweighed by the liability should it fall into the river, and its restoration having won a Saltire civil engineering award now he welcomes East Ayrshire Council's pledge after fifteen years to incorporate it in a cycleway.

Scotland's oldest surviving iron bridge dating from 1804 at Linlathen East near Dundee collected an ICE heritage and infrastructure award with a developer-funded restoration to tackle distortion after testing its blacksmith-crafted cross-beams with a force of 5 kilonewtons per square metre. At Craigellachie Telford's mighty crossing of the Spey dates from 1812-4.

An anthromorphic model of the cantilever principle marked the final gathering in 2012 of the Forth Bridges Visitor Centre Trust formed to promote awareness of the Forth Bridge in the run-up to its centenary. A book produced in 1990 that sold 7000 copies in English and 2000 in Japanese had each chapter written by a different civil engineer, with the last one by Ted Happold looking at how the Bridge might have evolved in another hundred years. Its collection went to the ICE Museum at Heriot-Watt, but the Trust's greatest legacy was to support with help from MPs Tam Dalyell and Eric Clarke the Edinburgh Evening News "paint our bridge" campaign against Railtrack's reluctance to give the Bridge the care that it deserved and now receives from Network Rail.

Dalginross at Comrie, Britain's first constrained-cantilever steel bridge, was refurbished in 2000 and received a Saltire commendation. Roland's "Dynasty of Engineers" told the story of the Lighthouse Stevensons who are commemorated by an ICE plaque in the Bell Rock shore station at Arbroath. At Aberchalder a lightweight suspension bridge across the Oich bypassed in 1934 is a survivor of over fifty such bridges throughout the UK and Empire.

At North Ronaldsay Roland successfully campaigned for the distinctive stone ball that acted as an unlit warning to mariners. The Union Bridge linking the Scottish Borders with Northumberland across the Tweed is after 193 years the world's longest-serving suspension bridge. Radar scanning of Loch nan Uamh Viaduct in 2001 revealed the presence of a horse-skeleton and cart that had long been claimed for the better-known Glenfinnan Viaduct. Wade's White Bridge dating from 1732 received emergency infilling in 2012. The Kylerhea ferry-landing retains its bespoke cattle slip installed by Telford in 1819.

Roland visited the flooded Rhibuie drove-road of 1819 for a television series with Griff Rhys Jones. At the Skye Bridge PHEW's involvement was confined to the bridge connecting with the lighthouse, but they were involved with design of the Falkirk Wheel. At Paisley Canal Station a plaque for the Telford 250th anniversary commemorated Blackhall, longest arch of the canal age, while the 7-arch bridge over the Tay at Dunkeld was celebrated as Telford's largest in the Highlands. ICE placed a plaque on the Melville Monument in Edinburgh's St Andrew Square, and the 1907 Titan prototype crane at Clydebank was last August celebrated by four British and US engineering institutions.

Annual PHEW visits promote awareness of noted locations off the beaten track. In 1997 a record attendance enjoyed a ride on the Jacobite steam train to celebrate the centenary of the start of work on Glenfinnan Viaduct. A visit to the North Highlands in 2007 took in some of Telford's churches, and last year's to the Borders led across fields to the mouth of soon-to-reopen Bowshanks Tunnel.

This year's on 4-6 July will be to Tayside, where it is now 27 years since fireworks marked the centenary of the replacement Tay Bridge. Before then an ongoing commemoration of John Miller will see unveiling of a plaque at his 176-foot Ballochmyle Viaduct on 25 April. Meanwhile an outcome of last year's visit is that the Union Bridge is now recognised as being at risk, with both the Scottish culture secretary and Northumberland County Council committed to restoration in time for its bicentenary in 2020.

Report and photograph by John Yellowlees.