Holding Back a Rising Sea

Last week I went to a presentation at MIT made by a group of engineers that are half way through building a high technology barrier to protect Venice from rising waters. The project goes under the name MOSE (Moses).

People standing in water in Venice

Tourists in a rather damp Venice

Venice is a city built on an island situated in a lagoon that has been artificially shaped by human intervention over the last 500 years. The problem of rising sea levels and storms has meant that the city is regularly flooded, and so the project is to build a barrier spanning the three large openings to the lagoon so that it can be sealed in times of high tide and storms.

The flooding has been exacerbated by works carried out in the 1980’s and 90’s to build an industrial zone that involved the drainage of marshland areas, leading to a softening of the ground that made the city actually sink.

This is a 50 billion Euro project, and one of the biggest of its type ever attempted. A look at the data about the Thames Barrier (the first of its type) shows that the problem of high tides is getting worse. It was closed four times in the 1980s, 35 times in the 1990s, and 80 times since 2000, but why?

Strangely enough the problem is related to global temperature rise as we might imagine but not so much because of the melting of the icecaps. The fact is that water expands when it is heated so warming even by a couple of degrees has the effect of increasing its volume. The International Panel on Climate Change state that 70% of the presumed rise will be due to this factor.

So back to the barrier. The entire project is quite an undertaking as this YouTube video demonstrates. Years of planning followed by years of preparation, reclamation of marsh lands and sea defense construction not to mention the construction of an off shore oil terminal so that the ships no longer have to enter the lagoon. But Criticism is also rife.

An aerial shot of part of the MOSE project

Part of the finished engineering works on the MOSE project in Venice

Some engineers criticize the project on purely technical terms, other groups point to the lack of environmental impact study and others the cost.

This video also on YouTube tells a completely different story to the one above. Critics are arguing (amongst other things) that we do not know all of the variables involved (which seems to be true) and that the entire ecosystem of the lagoon will change.

I am no engineer so I cannot argue about the choices made, but I do have one simple question. With all of the movement of water involved in this project (serious high tides and the passage of thousands of liters of sea water a minute) would it not have been possible to build something that produced electricity instead of consuming it in huge amounts?

Venice's flood defense plans

Details of how the flood defenses will work

The stakes are high as you might imagine, Venice is one of the most touristed cities in the world, but the high tides are flooding the monuments ever more regularly. We are talking about more than a meter of water, and footage on international TV of tourists walking on raised platforms through St Mark’s Square and fresco covered churches full of water does not go down well.

It is an old problem though, and one that is shared by many cities today. New Orleans is discussing a similar solution, and here in Boston the issue is also under debate.

They are all looking for a high technology solution to an age old problem that is getting steadily worse.

Think about your water usage

How often do you think about your use of water? Serious question, one which some of our readers will undoubtedly say all the time. Those living in areas of almost constant drought will have water as a very pressing issue on their mind, most of the time.

But then there are some of us, who might not really consider it as much. The authorities are in control of it right? If they aren’t, strictly regulated private companies are, so we are good, yeah?

Water is a resource which we all need, and cannot possibly live without. Whenever scientists are looking for life on other planets, one of the first things they try to work out, is was there ever water on this planet, and is there now? Why? As water is a key component to life as we know it.

Sadly, water is a very scarce resource, and according to National Geographic, a mere 0.007% of our planets water is drinkable. That’s right, just 0.007%. The rest is in the oceans, and the majority of the 3% of freshwater left, is locked up in ice, which ultimately melts into the sea.

0.007%

As I am sure you heard, in October last year, (2011) the earth’s population reached 7 billion, and is still growing. That 0.007% figure is not getting any bigger, but the population is – rapidly. That is why, currently, on the earth:

One in Five People Don't Have Access to Safe Drinking WaterThat’s right, 1 in 5 people living on our planet does not have access to a safe supply of water which they can drink. If the population is 10 billion by 2050, that statistic could increase to 2 in 5, or maybe even 3 in 5.

In the 20th century, the global population tripled, the use of water sextupled – grew by six times. Los Angeles can support around about 1 million people with its water supply. It currently has a population of 4 million – see a problem? Elsewhere in the USA, in less than 5 years, Central Florida could potentially run out of water.

Drought

Some places in the world are naturally dry, and frequently suffer drought. Some places are naturally wet, and frequently suffer flooding.

The thing is, most of us probably don’t think we are in drought right? Say you live in the UK, like me, you probably think our water supplies are fine yes? Recently in the news we have been notified most of the UK is in drought, but are we really? Well the answer is yes, and many other areas of the world might be too, you might not realise it, but where you live could be. Check out this drought monitor, to see if your area is. You can toggle the time period on the left hand side, as you may be in long-term drought, but not short-term and vice versa.

Look after it

We all need to learn to look after our water better. We are not getting any more, so we need to be more careful with what we have. Our lives quite literally depend upon it.

My question to you is how much water do you use? According to Thames Water we use around 8 litres every time we flush the toilet. Brushing our teeth with the tap off uses 1 litre, whilst brushing them with the tap on (assuming a 2 minute brush) uses 12 litres. Our dishwashers typically use 20 litres, whilst our washing machines thirst for a giant 45 litres.

Hose pipes

Everyone always moans when we go into a hosepipe ban. What is the point? Surely I use just as much water as other activities, so why ban that? Well it doesn’t. One toilet flush is around 8 litres, but one hour of hosepipe use is 540 litres. That’s right, 540!

Lets assume you are washing your car. Say it takes you 20 minutes. With a bucket, you would typically use 10 litres – 2/3 buckets. What about with a hosepipe? Well, you would use 18 times as much water, a staggering 180 litres!

More refugees (25 million) were displaced by contaminated rivers in 2008 than were forced to flee from war zones. I don’t have more recent figures, but I would assume the figure would be much greater. The UN state that around every 15 seconds, as child dies from a water-related disease – poor sanitation, which 1 in 3 people on the planet suffer from.

One in Three People Lack Access to Adequate SanitationHow can you save it?

Depending upon how much you use, will determine how much water you could potentially save. Here are some great starting points:

  • Turn the tap off when cleaning your teeth – you could save 11 litres
  • Fill your kettle to the minimum you need, don’t fill it half full, or to the top if you are only making 1/2 drinks!
  • Use a bucket to wash your car and save yourself 170 litres
  • Don’t put your dishwasher or washing machine on until it is full – two washes uses twice as much water
  • Don’t leave the tap running when washing up or cleaning vegetables
  • Fix leaks – if you have one dripping tap, it could use a staggering 3,120 litres a year!
  • Take a water test, to see how efficiently you are using your water

Saving water is very important, and it can save you money.

It's time to give water a second thoughtPlease, think about your water usage, as it is something that affects us all.