Resilience in future water supplies

Water is our most precious resource: drinking water and wastewater services sustain core functions of society, and of course human life itself. But our water systems are dogged by ageing infrastructure, floods, droughts, storms, earthquakes, sea level rise, population growth, pollution, and even cyber-security breaches. And speaking with Chris Smith is the man who worries about all of this, and tries to develop strategies to surmount these problems, Virginia Tech’s Sunhil Sinha…

Sunil - The problem we are addressing here is related to water infrastructure. A lot of people don't realise how water comes to their tap or, when they floss, what happens. There is an infrastructure which takes care of drinking water, wastewater, storm water. The challenge we are facing is because of climate change and also ageing infrastructure. How do we make this infrastructure more sustainable and resilient?

Chris - That's going to vary depending upon whether I'm talking about, say, London, somewhere in the US, or rural India, isn't it?

Sunil - Yes. But, firstly, we are talking about making this infrastructure resilient. First, we need to think about why we built this infrastructure in the first place: to provide a service. A service to the citizens and a service to the economy/industry in that area, the community. Infrastructure needs to provide a service not just under normal conditions, but also under stressed and catastrophic events. So whether it is in London or in India or other developing countries, the hazards will be the same. If a hurricane is coming, a sea level rise, an earthquake, it'll impact the infrastructure. The scale will be different because if it is in a developed country, like London and in the US, the damage will be greater. Also, it depends how we build this infrastructure in the first place. So you are right, the scale, location, we have to take into consideration these multi hazards.

Chris - One thing we have to consider though is, in order to work out how big the problem is that we are grappling with, we have to understand what we have already and how big the problems are. Have we got a sort of framework already?

Sunil - No. That's a good point you raise, understanding the problem. Right now we are facing, if you look at climate change or a natural disaster, if it is coming in a 100 year or 50 year timeframe, most of the infrastructure we built is based on these conditions. But now things have changed. The baseline has changed. We are seeing these hurricanes, natural disaster frequency has increased. Intensity has also increased. It's not the same. Hurricanes are now coming every year. They are coming at level 4, 5. Now we need to think about this infrastructure, how we strengthen it, or retrofit or adapt this infrastructure. We can't build in the same way that we built this infrastructure 50 years or a 100 years back. With this new baseline, we need to think outside the box and come up with a new standard, new design practices. How are we going to build this infrastructure, also, how are we going to retrofit, because we are not going to build everything from scratch. That's important. You brought up the question of developing countries. In developing countries, they are building a lot of this infrastructure, so they need to consider this when they are building this new infrastructure. How are they are going to sustain and also make it more resilient so that it can provide a service not just for this generation, but for your kids and grandkids.

Chris - How good are we, though, at anticipating the threats ahead? I'll give you an example. The population of the UK has risen by millions in the last couple of decades, largely driven by migration. There's now a housing crisis and people are saying, let's just build more houses. But at the same time people are turning around and saying, but what are the people who live in these houses going to drink? Because no one thought, well, if we bring millions in, they're going to drink millions more litres?

Sunil - That's why we need to look into a whole system approach. We can't just do it randomly, or make projections, because a lot of things are changing. You mentioned the population growth. Resilience is not just building this infrastructure and making it more robust. We can't do that. First of all, we don't know what will happen 20 years down the line, how the climate will change or what other stresses will come. These are dynamic in nature. We need to be more smart and digital technologies are helping us. In the US also, if you carefully look at the US population, it's moving where there is no water, like in Arizona and Nevada. We need to think now on a bigger scale with a whole system approach, looking at where these ageing populations are. People want to live in Florida because of the coastal areas but, with sea level rises, it's not that easy, because you can't even now buy a house in Florida and pay the insurance because insurance companies are not willing to insure it unless your house is retrofitted to a certain level. That's going to cost a lot because, now you are talking hurricane level 5, your roof will cost 10 times more. We need to be more systematic. We need to look from the whole system perspective: how are we going to make the policies and law. Not everything can be done by law. Also, we need to educate our people as to the threat we are facing, and not just short term but also long term. Education is important.

Chris - You've put forward some possible solutions there, but it seems like an enormous problem to try and grapple with, to try and do this across the entire world, and it doesn't sound like we've got very long to do this?

Sunil - But you see, we are at the tipping point. Climate change, natural disasters, every time any disaster comes to the US, it costs billions of dollars. We need to think harder about how we are designing this infrastructure. It can't be the same old story that it was a hundred years back because, as I mentioned, the baseline has changed. We need to be smart now. Fighting with Mother Nature because of climate change, we need to think about how we are designing cities and towns, how we are sustaining, maintaining it. Otherwise it'll become too costly to sustain.