Some key macro trends
of the present and future

By Mark Lane

Principal, Mark Lane Water Consultancy Ltd

The launch of the Arup InDepth Yearbook is a suitable occasion to consider a number of key macro trends relating to the present and the future, which provide a backdrop to the Yearbook.

Climate change

It is beyond doubt that climate change is happening, whatever the sceptics may say .Whether or not the COP 21 Paris Conference makes a difference, the die is already cast for the next 35 years at minimum. Those of you who have listened to speeches made by the immediate past Government Chief Scientist, Sir John Beddington, will know that when he spoke on this subject, a key point he would habitually make is that we are already encumbered with the consequences of past actions and inactions up until at least 2050 in the context of climate change.

So whatever steps the global community now takes, we cannot escape the consequences that are already embedded due to our past behaviour towards the planet. That means increased desertification globally, increasing climate extremes as the planet warms up and consequent increased water stress.

So far as the UK is concerned we can expect shorter but more intense rain episodes. This of course has consequences in the field of flooding and flood protection, as has recently been demonstrated in the North of England and Scotland.

Population growth

Population growth, urbanisation and industrialisation are projected to increase global demand for water by 55% by 2050.

The world’s population (according to the UN World Water Development Report 2015, Water for a Sustainable World) is estimated to increase from 7.3 billion people in 2015 to 9.1 billion by 2050.

The same Report (together with the OECD Water Outlook to 2050 ) predict that in 2050 52% of the world’s population will live in water stressed areas; 240 million people will not have access to an improved water source ; and 4 billion people will not have access to basic sanitation.

The move to the cities

In parallel with this explosive population growth, there will be an unprecedented population surge towards the world’s bigger cities particularly in Africa and Asia.

The UN Report that I have already referred to predicts that by 2050 global urban populations will have increased by 60% from 3.94 billion in 2015 ( 54% of the total global population ) to 6.3 billion (70% of the total global population ).This will pose unique infrastructural challenges for African and

Asian countries where 90% of the growth is predicted to take place.

It is interesting to note that Africa is predicted to experience a 16% rise in urban population by 2050 – making it the most rapidly urbanising region on the planet.

Currently only three African cities – Lagos, Cairo and Kinshasa – fall within the definition of “megacities “i.e. a city with a population of 10 million or more.

Within the next 20 to 30 years the rush to urbanisation in Africa will push at least another six cities – Johannesburg, Luanda, Nairobi, Addis Ababa and Khartoum into the megacity class, and many others will be near that level- from Maputo to Dakar.

So what can these people expect when they move to the cities of Africa? Of course conditions will vary, but I venture to suggest that unless major steps forward are taken regarding the delivery and maintenance of water and sewerage infrastructure, the experience of Nairobi might not be untypical.

Let us look at Nairobi. In Nairobi, overall 60% of the Nairobi population lives in 6% of the land comprising Nairobi. The largest slum quarter in Nairobi is Kibera. The number of people living here ranges from 500,000 to well over 1 depending upon which slums are included in defining Kibera.

The conditions in Kibera are such that it is in effect a “no – go “area for both the army and the police. It is controlled by criminal gangs who exert control over the residents, amongst other means, through their control of the water supply.

Unless major action is taken, the Kibera factor will become a feature of an increasing number of African cities as their population grows. These cities are likely to become increasingly dysfunctional.

All three of the macro trends mentioned above interrelate – Climate Change; Population Growth; and The Move to the Cities. Between them they give rise to a fourth macro trend. This fourth one is migration. This is of course not solely and African issue, and it is greatly exacerbated by geo- political factors in the Middle East and elsewhere.

Africa is set to more than double its population between now and 2050 from 1.1 billion to 2.4 billion. Fertility rates currently average 5.2 children, compared with an average of 1.6 in Europe. In 35 years, three African states, Nigeria, The Democratic Republic of the Congo, and Ethiopia, will be in the top ten of the world’s most populous countries. It is from the cities that form the bursting hubs of Africa that migrants will come, unless the water infrastructure of these cities is resolved.

Since, as we all know, quality of life begins with an efficient supply of clean water and an efficient sewerage system.

I leave aside the stimulus to migration caused by war and civil war as it is a well aired topic. The situation however will be compounded by those fleeing from countries whether in Africa or the Middle East where the water supply has simply run out.

For example, various estimates predict that the capital of the Yemen, Sana’a, could run out of water within a decade or as soon as 2017. If the 2.3 million residents of Sana’a don’t have water, they will take their chances and move.

It scarcely needs mentioning that all of this is likely to make Europe’s current migration issues appear to be relatively minor irritants.


The macro trends discussed above are a matter of deepening concern for the global community. The Arup InDepth Yearbook provides a key factual catalyst towards stimulating discussion on how best to address these issues.

Biography – Mark Lane

Mark Lane is a Director of The UK Water Partnership. He is Chairman of Flood Advisory Service. Mark chairs the UKTI Environment and Water Advisory Group. Mark chaired the group of 26 experts who wrote in 2013/14 the Report ” Tapping the Potential: A Fresh Vision for UK Water Technology”. The recommendations of this Report led to the formation of The UK Water Partnership.

Mark was a partner at international law firm Pinsent Masons for 25 years, where he founded in 1995 the firm’s Water Group, which he led until his retirement from the firm in 2013. He first developed the firm’s water technology showcase events (Wet Networks) nine years ago. For the past three years these have been undertaken with Arup as a co-stakeholder. Mark now works as a Consultant to Pinsent Masons.

Mark is the principal of Mark Lane Water Consultancy Limited and acts as a Consultant to a number of companies in the water sector. Mark is a Court Assistant of The Worshipful Company of Water Conservators, and a Trustee of The Water Conservation Trust.