Just as it is not in Nature to fail, so I believe it is not in our nature to fail. Your institution has shown just what humanity can achieve when we put our minds to it.

Ladies and Gentlemen, perhaps I could just begin by thanking your Institution and Halcrow for taking such a courageous plunge and inviting such a formidably under-qualified, non-engineer to address such a formidably knowledgeable audience.

As I am more qualified as a historian, when I was preparing for this lecture I took a moment to consider the wording of your Royal Charter, which was granted in 1828 at the apex of the Industrial Revolution. As I am sure you all know by heart, the preamble describes Civil Engineering as “the art of directing the great sources of power in Nature for the use and convenience of Man.” This definition brilliantly captures the scope and ambition of your work and it contains two important elements which I would like to explore.

Note that word “art.” Clearly that describes you as being more than technicians. It's a point I'd like to come back to, if I may. But I would like to begin with the second part of the definition because it seems to me that if we are to address the many accumulating challenges confronting us today, we need to be a bit more respectful of, and attentive to, those powers of Nature.

Civil engineering is, of course, a life-saver and a life-preserver. We have your former President, Joseph Bazalgette, to thank for the drains and sewers which have lifted millions out of foetid conditions in cities across the world. Other members of this institution have built bridges to span rivers and link remote communities; railway lines and tunnels that enable us to travel from London to Brussels in a couple of hours; power stations that provide us with electricity and light. And today your members are responsible for conceiving how we will build a new energy system that could be near zero in carbon, low-carbon transport systems and water-management solutions that will keep people alive in increasingly arid parts of the world. If there is one profession that has awoken to the need for more sustainable approaches, it is civil engineering, putting you firmly on the front line in the battle for sustainability. I hope that doesn’t come as a shock to you! Although I would add, there is more to sustainability than a thing’s functionality.

What has occupied me for a very long time is quite why, with all our technical knowledge, we find ourselves facing the threat of catastrophic climate change. I fear the answer lies in the very words in your Royal Charter – we have been all too willing to direct and use the power of Nature for our own ends, with scant regard for the long-term consequences of our actions.

I don’t have to tell you about oil prices, climate change, droughts or floods. It must be obvious to a room full of engineers that we are plainly exceeding the capacity of the planet to provide us with many of the natural resources we use and to accommodate all the waste we produce in return. It is sobering to consider, for instance, that we are now using so much water that some of the biggest aquifers that irrigate the bread baskets of the United States are depleting considerably faster than the rain can replenish them, or that, because of the continued burning of thousands of acres of ancient rain forest every single day, during periods of drought the Amazon basin becomes a net emitter of CO2, a reversal of its natural role as a net carbon sink. Every year, three-quarters of the world’s fisheries are over-fished and many face commercial extinction; the rate of species extinction worldwide is currently a thousand times greater than the natural, evolutionary rate – which means a quarter - yes, a quarter - of all the birds and mammals on Earth are in danger of extinction.

Any sane individual, and certainly people as practical as engineers, are surely moved to ask the question – how much longer can we go on like this, living so wilfully beyond our means? We may well have created a technologically sophisticated human world, but I'm afraid the evidence speaks for itself. We have, by default, engineered something of a looming disaster and we need all the ingenuity we can muster to pull back from it. And, dare I suggest it, perhaps a little humility too, in terms of the need to work more closely in harmony with Nature – even to rediscover the value of traditional engineering techniques that can be applied in a modern context.

The process involved in developing all of our sophisticated technology has, it seems, persuaded us to think we are somehow a disconnected part of Nature when, in fact, if you think about it, we are Nature. The patterns and processes that govern Nature also govern us. It is worth reflecting on this subtle shift in perception because we need to see how a purely mechanistic way of thinking, focussed as it has so often been, on one particular problem or one intended outcome alone, contributes to the problems we have today. We cannot ignore Nature's ways because they are a part of us too. This should, perhaps, have a profound effect on how we conceive our engineering projects.

Two years ago I published a book which I wanted to call “Harmony.” For some reason it was extraordinarily difficult to get such a simple title accepted. But the real reason for that title was that, using a wide range of examples from a variety of different disciplines, I wanted to demonstrate that Nature itself is a harmonic system, and that if we ignore the principles that sustain that harmony, Nature's essential balance and equilibrium become quite literally “dis-ordered.”

One of the examples I used in the book was how water behaves. As I say, I am no engineer, but in the course of countless visits to flooded areas in this country it became apparent that so many of them were caused by the way we had ignored Nature's way of alleviating these problems and not understanding enough how Nature herself deals with water. We have tended to centralise systems, channelling the water towards high capacity collection points; we have built right up to the river banks; we have made the channels deeper and we have paved over all our towns and cities. Since the 1970s, an area twenty-two times bigger than Hyde Park has been paved over in London alone.

All this ignores the fact that Nature does not depend upon such a centralised system. On the contrary, Nature depends upon a network of multiple pathways – just as our own bodies do. Brooks, streams, rivers, bogs, water meadows, these are all part of a system which our engineering in the mid 20th Century appears to have thought we could do without. And yet they are elements in an integrated system with a necessary, built-in redundancy, which is actually there to serve the balance of the whole. It is a harmonic system. So, when the unexpected, massive storm occurs, the run-off has plenty of places to go. By blocking off those options, or concreting them over, the run-off has nowhere to go and so we tend to see sudden, devastating flooding in our towns and cities.

It is encouraging that we now have much better monitoring, warning systems and a refined approach to the risk of inundation, which seems to be taking more notice of how Nature tackles the problem. We are beginning to see a reintroduction of wetlands, water meadows and natural storage and drainage systems, but it surely has to be a much more significant movement than it is at present...

Although it was extremely novel at the time, I was certainly delighted that my Foundation for Building Community was able to encourage the use of Sustainable Urban Drainage Systems at Upton, a development on the edge of Northampton, where an extensive wetland swale system is now part of the town plan, making it not just practical, but attractive too. Such features of the landscape also happen to enhance the experience of living and working in a built environment. And this is important. Taking a truly integrated approach is the way to improve human well-being as well as protecting it. And I would hope that this is one area where the I.C.E. and Halcrow could collaborate much more with my Foundation.

Incidentally, I am delighted that Halcrow and the Institution are already working closely with three of my organizations - not only my Foundation for Building Community, but Business in the Community and also the Cambridge Programme for Sustainability Leadership. Each, in its own way, has been looking at these various issues for quite some time and considering how we might change our approach to meet them in a way that supports a burgeoning world population without completely compromising the future well being of our grandchildren. Of course, whether we can do this when faced by the projected population of nine billion is beyond my limited intellectual capacity – but I could hazard a guess.

Thus, the Cambridge Programme for Sustainability Leadership, of which I am Patron, has been working at my request with many leading firms to develop a narrative around the concept of Natural Capital that can be understood in the board room. Influential companies with a global reach are working to address the impact that the loss of ecosystems and Natural Capital is already having on businesses, their customers and on society as a whole. Business in the Community, of which I have been President for over a quarter of a century, has established a project called “Visioning the Future,” under the leadership of Ian Cheshire at Kingfisher, to show just what a sustainable business might look like, while my Foundation for Building Community, since I founded it twenty-five years ago, has been looking at the whole question of a sustainable approach to planning, designing and building urban settlements at a time when more and more people are living in cities. It is an approach that not only looks at maintaining Natural Capital, but how to maintain and enhance Community Capital. And Engineers have a great part to play in this task. Which is why, at my Foundation, we take the radical step of encouraging engineers to pick up a pencil and draw, to go out and look at how streets work... and even – wait for it – ask them how it makes them feel...!

Too often I find that the design of certain projects is carried out with scant regard to those aspects which have the greatest impact on the people who will live with the results. I am sure you know the experience only too well. Someone else comes up with a scheme that you, then, have to make work. Which risks the possibility that, although the technology works brilliantly, the installation may not be as attractive as it should be to the people who have to live and work in its midst. If this is a familiar scenario then I would urge you to see that you do have an important role to play in this regard.

This is just as important as how a thing works. I have been engaged with this combined approach for what seems like a very long time and what has emerged time and again is essentially the same point – if we take the trouble to rediscover time-honoured, traditional approaches and consult local people at the grass roots, we can develop the sorts of solutions for our cities that could make them truly sustainable in the roundest sense. For various reasons these approaches were either abandoned or even blown apart in the last century, and yet they are the result of an understanding acquired over hundreds, if not thousands, of years – how to build towns and cities that hold together as coherent, interconnected entities that enhance communities rather than fragment them.

So much of modern thinking seems to have ignored the importance of looking to the long term. Take the way we have been constructing buildings during my lifetime. We build in a short-term manner, creating neither durability nor, for that matter, beauty; thus generating, instead, a maintenance burden rather than an asset for the generations that will follow us. Buildings are still too often constructed out of materials that are deeply environmentally unfriendly. Glass, steel, concrete surely all fall into that category - because of the embodied energy in their production - especially if they are incorporated into designs that are very much “in the moment.” I'm afraid if a building is of a fashionable design today it almost inevitably condemns it very quickly to becoming unfashionable – tired looking, out-dated, no longer “contemporary.” And so, within thirty or forty years, they are ripe for demolition and replacement.

From the practical point of view it is perhaps worth noting a study conducted in 2009 by the architect, Professor Robert Adam, who worked with the environmental consultancy, Atelier 10. He compared the energy performance of two buildings – one modelled with a typical lightweight facade made of glass, and one using a much more heavy facade, mostly masonry. The results clearly showed that the energy consumption of lightweight building types is consistently higher than those with good thermal mass, particularly for residential use. What's more, the internal temperature in those lightweight buildings fluctuates considerably. It greatly exceeds the temperature people find comfortable in the warmer months if the glazing remains unshaded – which, of course, requires more energy for air-conditioning.

And then there is the aesthetic. That word in your Charter, “art”, needs to be remembered. I need hardly say that this is something architects get rather touchy about, but whereas a typical modern building has a lifespan of seventy years or, as I say, often less, the spaces around that building last much longer; sometimes for centuries, even millennia. So how we design those spaces, how we control the movement patterns and so on, has a very big impact for a very long time - and not just practically, but in the way they make generations of people feel. Engineers surely need to be as mindful of this aspect of their work as they are of the practical.

After all, you only have to ask yourself where you like to live? What kind of environment appeals to you? On a daily basis, what do you want to look at out of your window? As a historian, I have always been moved by the way your predecessors took the trouble to ensure the infrastructure and major buildings they created – the sewage works, the power stations, the aquaducts – were not just functional blots on the land or townscape, but worthy, civic neighbours that were a pleasure to behold. This is not as apparent, I'm afraid, in the legacy of the 20th Century approach.

In the 21st Century, we are, perhaps, slowly becoming aware of its limitations and of the need to develop a more integrated and longer-term approach; one that avoids these adverse environmental and social effects. The challenge, of course, is how to translate the alternatives into the heart of the mainstream...

Hence, therefore, my Foundation's involvement in the building of a “Natural (low carbon) House” at the Building Research Establishment in Watford. The aim has been to create a new model, built on site which could easily be adapted for volume building. Its design has a contemporary yet timeless feel, so that it won't look tired and old within a decade or so, not least because the design is based on time-honoured, geometric principles of balance and harmony. It does not wear its green credentials like a collection of “eco-bling,” but all the same it is made of something other than conventional bricks. It uses new, inter-locking clay blocks. They are low-fired, so they do not produce much carbon; they are much quicker to lay and are moulded in such a way that they breathe. They keep the building ventilated and cool in warm weather, but they also have an astonishing capacity to insulate. These blocks are then rendered in lime and hemp with an internal fibreboard. The roof tiles are made of clay and the roof is insulated with a remarkable material I have been urging the building industry to use for some time. You may have heard of it. Not only does it provide great insulation and is free of harmful chemicals, it lasts a very long time. It disperses condensation and ventilates roof spaces in warm weather, and it is also extremely non-flammable. It’s called wool.

I must say I have been encouraged not only by these developments, but also by the fact that many noted architects, some of them very well known Modernists, are now openly talking about the need to move away from creating enormous, energy-guzzling glass boxes and towards a more environmentally sensible approach. So, if I may, my question to you, ladies and gentlemen, is how might you as engineers help to nurture these tentative green shoots?

I am sure I do not need to point this out, but being, as you are, at the heart of making design work, you are powerful agents of change. I have followed very closely how civil engineering, informed by advances in science, is now beginning to work in an integrated way with other disciplines, to seek better ways to manage energy and water much more efficiently. Your thinking is creating better systems of supply chains that reduce the carbon impact of new building and, indeed, the retrofitting of existing structures. I have been fascinated by the way engineers have managed to install in old buildings energy-efficient techniques like passive heating and cooling systems. And I have been a long and somewhat lonely advocate of an emerging discipline that still does not get the public attention it deserves – biomimicry, which combines what zoologists and biologists know about natural systems with the problems engineers are trying to solve.

This is why I have always been keen to see an engineering component in the educational work of my Foundation for Building Community and it would certainly be enormously encouraging if the I.C.E. would ever consider working with my Foundation to include a sustainable engineering element in the courses it runs during its Summer schools. Likewise, I am delighted that my Foundation and Halcrow are exploring the possibility of developing a secondee scheme involving staff from Halcrow and other members of the I.C.E. - the purpose being to encourage engineers, along with the other professions, to be there at the start of the design process and to ensure a more integrated approach that lengthens the longevity of buildings and infrastructure so as to nurture human wellbeing and community.

And this leads me to suggest that if we could really marshal our forces in this way, by taking the innate ingenuity and inventive capacity of British engineers, we could work to make parts of this country recognised as real centres of excellence for environmental engineering and the kind of technology that draws on Nature's own ingenuity.

This is not some sort of pipe dream. I am not sure that there is a proper appreciation of the real urgency with which we have to adapt our approach, given that the economic landscape has changed so dramatically in recent years. We are now in a new and very different economic paradigm, it seems to me. We are not living in some sort of temporary, economic bubble where the prices of raw materials are only artificially inflated for a short time. I was recently shown how the price of iron ore fell throughout the 20th Century and how, in the past eight years, it has surged to a 110 year high. This price bubble will not burst, I'm afraid, because there is no bubble! This escalating shift in the cost of raw materials is a permanent one, so we are operating in a very different market.

This is why I have long suggested that we have to turn to a much more integrated and truly sustainable way of doing things. Not just because of the moral imperative to be more “environmentally friendly,” but because we simply cannot afford to be as profligate as we have been.

The challenge, then, for civil engineering, is to be concerned not only with how a project might work from a technical point of view, but also how such technology sits within the public realm and how it will affect the communities it touches. All of the professions need to integrate their skills as much as possible, an approach that has to be reflected, surely, in the way the educational establishments operate too. So do engineering courses, for instance, give enough consideration to the concerns of the other disciplines, and also to the public aesthetics of their own? And, ultimately, are we encouraging young engineers to learn as much as possible from the lessons of Nature – so that they not only “direct” her powers, but work with them much more?

This great institution is an exemplar for me of that innate tendency in humanity to improve the well being of people. Just as it is not in Nature to fail, so I believe it is not in our nature to fail. Your institution has shown just what humanity can achieve when we put our minds to it. It should be a source of great pride that so many of the greatest civil engineering projects have come out of the vision of your members. But you now carry their legacy on your shoulders and, as you reflect on the challenges that face us in the 21st Century, I would urge you to consider carefully whether those words in your Charter are still as relevant today as they were in the 19th Century when these problems were not apparent.

Perhaps it is time to revise them for the task ahead and refocus the definition of what it is to be a Civil Engineer – expanding a little on the meaning of that word “art” and, rather than “directing Nature’s powers,” understanding them properly so that we work according to their underlying patterns of behaviour.

It is those patterns that sustain Nature’s precious gifts. And it is beholden upon us to preserve those precious gifts for the generations who follow us. I may not be an engineer, but as a historian I can say with some confidence that our lame excuses will look very weak in their eyes if we do not.