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About Harvey, part 2: Messrs. Claudius, Clapeyron, and Mann

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One completely unexpected consequence of Hurricane Harvey: it has caused the Clausius-Clapeyron equation to be mentioned by the mainstream media.  A Google search reveals that Wired, the Guardian, the BBC, LA Times, the Washington Post, and Bloomberg have all mentioned the equation in the context of the Hurricane (and that’s just Page One of the search).

You have to thank climatologist Michael Mann for mentioning the equation (in a Facebook post, of all things) and explaining its significance: every time the air warms up by one degree centigrade, the air can hold up about 7% more moisture.

The equation itself is fairly complex (and its derivation scary – two pages in Wikipedia, and they simplify) but there is an approximation, the August-Roche-Magnus formula, that makes the point that it is an exponential relation, like compound interest:

This is the equation I’ve used in class, because it is accessible to anyone with a scientific calculator (yes, that’s what the button ex  is for).  It relates a fairly arcane complex (the water pressure) to the ambient temperature.  I say arcane because water pressure is just another way to say how much moisture is in the air.

I always find it interesting, if not downright nerdy, to figure out who these people were who gave their names to equations.

Rudolf Clausius

Rudolf Clausius was born in 1822 in what was then Prussia (in the town of Koszalin, now in Poland).  From what I can gather he was an exemplar of the Prussian cliché: very exacting, he gained fame by demonstrating that the thermodynamic laws of the time contained a contradiction, and restating the equations so as to make the problem disappear.  (In other words, the fact that the equations his colleagues used then worked well enough was not good enough for him.)  He also was the first to express in mathematical terms the mind-boggling concept of entropy.

Clausius got his PhD, a relatively new degree, from the university of Halle, in 1847. Prussia had recently acquired Halle and the area around it in 1815.  The old university became integrated into Prussia’s effort to increase its general education performance, especially in the applied sciences (Prussia had by then the most educated population of the world).  Clausius went on to teach in Berlin at the Royal Artillery and Engineering School.  He married twice and had seven children.

Benoit Clapeyron

Benoit Clapeyron was born in Paris in 1799, just at the start of the Napoleonic wars. He became an engineer developing the then-newfangled technology: the railway and its steam engines.  In 1834 he published an essay on the ”motive power of heat”, which was the first publication to feature the graphs of steam volume versus pressure (the very graphs dreaded by all engineering students in courses such as Intro Thermodynamics). By all accounts he was an eminently practical man, working on the practical problems of his era, be they better steam engines or bridges (for which he is equally famous in engineering circles).  He was presumably well connected, and married into the Bazaine family (the sister of the future Grand Marshall of France).  He died at the age of 64, having enjoyed a fine teaching job at the Ecole des Ponts et Chaussées, and what had been then the longest uninterrupted period of peace in Europe.

Clausius and Clapeyron apparently never worked together; Clausius reworked the French scientist’s equation from first principles, in a document published in 1850 (hence the name of the equation).  One wonders what they would have said to one another.  But in the era when the bulk of thermodynamics work was written, the France of Napoleon III and the Prussia of Bismarck eyed each other suspiciously.  As it was, Bismarck was to manufacture a diplomatic incident that led to the 1870 war between the two countries, which led to the complete defeat of France (led by Clapeyron’s brother-in-law Bazaine) and the unification of Germany.  Clausius organized an ambulance corps for the German side, was wounded during an engagement, received a medal and a permanent disability.

Penn State’s Michael Mann

What would these two have thought of Harvey and climate change?  They would have been interested, no doubt.  But maybe they would have also been surprised by our inability, 150 years later, to tackle the problem.  They probably would have also applauded climatologist Michael Mann’s intervention away from the ivory tower of science and into the public sphere; the idea that scientists should stay quietly in their labs was not current then.

Then again, having witnessed, one the devastation of the Napoleonic wars, the other the absurd horror of the Franco-Prussian war, they may have just shrugged and rolled their eyes in dismay.

Be that as it may; the silver lining is that, finally, science has regained its rightful place in the discussion.

 

 

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Written by enviropaul

September 4, 2017 at 11:39 am

About Harvey

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Thirteen years after Katrina, watching Hurricane Harvey seems like a rerun – except worse.

Here’s a quick run-down of the information about the storm itself – it will take much longer for the tally to be complete, but we know there has already been loss of life.

SciAm ran an article discussing the physics of the storm, and it’s one of the best I have seen.  The storm power increased really fast, just like Katrina’s did, because it traveled over a blob of very warm water, warmer than average for the Gulf of Mexico, which itself as a whole has been unusually warm.  (Very warm water evaporates easily; once it condenses in a cloud, it releases latent heat, and it is this heat that provides the energy of the storm.)

But why isn’t it weakening now that it’s overland?  The answer to this is surprising.  The storm has weakened, but not much.  That is because such a large area that is normally land is now under water; typically, if more than 50% of the area is flooded, it might as well be an ocean as far as the hurricane is concerned; it needs only shallow water to keep feeding, so to speak.

And why is it not moving?  This one is more complicated.  Meteorologists talk about blocking highs.  These are areas where ridges of high pressure (aka, nice weather makers) dominate.  Normally these high pressure zones channel winds away, and the hurricane rides along; but there are two distinct highs, competing, so to speak, so these winds cannot establish themselves.

A hurricane causes damage in two ways: high winds, and flooding.  Of the two, flooding is often the worse, because it lasts longer and is more pervasive.  Flooding is usually the result of a number of factors.  Of course, rain is incredibly intense; some estimate that about 800 millimeters will fall during the passage of Harvey, and that is about half of what falls on Vancouver in a year.  Such rainfall quickly overwhelms the capacity of storm drains.  But even that water that does pour down the storm sewers and the ditches needs somewhere to go, and local rivers and creeks are often overwhelmed as well.  Finally, there is the storm surge effect.  A hurricane is a “depression”, meaning that it is a zone where atmospheric pressure is unusually low.  This is like a partial vacuum, and as a result the sea level rises under the storm as if it were sucked up by a vacuum cleaner.  This is called a storm surge, and this is what caused most of the flooding after Sandy in New York and Katrina in New Orleans.  Harvey’s surge is about one meter, which considerable, but not as high as these other two storms.  But the shape of the shore may create a funnel effect; the surge in Galveston is about 2.5 meters, nearly three times as high as in the open ocean.

Flooding may be made worse when dykes suddenly brake, of course, as happened in New Orleans (where flooding was made that much worse because much of the city, such as the Ninth Ward, is below sea level).  Houston is above sea level (not by much) and there are no dykes around in a way similar to New Orleans.  But dykes may yet cause trouble.  Two of the flooded areas are the Addicks and Barker reservoirs, which prevent some of the flood waters from entering Buffalo Bayou, the stream that flows through downtown Houston. If these dykes break, the flooding may become even worse; but so far so good.

So Harvey is a rather anomalous, both in its intensity and its insistence of hanging around.  Is this caused by climate change?  Wrong question, replies Michael Mann.   This would be like asking whether steroids can “cause” a gold medal.  Steroids or climate change, all that can be said is that it’s likely to have been a contributing factor.  Most likely the blob of warm water has been made warmer by climate change; the blocking highs may also have a link to climate change, but that remains to be determined.  Of course, we also know that a warmer atmosphere can hold more water vapour.  I found three good articles on the topic in the New York Times, Joe Romm in ThinkProgress, and Vox.

Compare this map with the one above: part of southern Texas has been turned into a bay, as far as the hurricane can tell…

But climate change or not, much of Houston’s flooding come from the city’s cavalier attitude to development.  What is called “green infrastructure” has been mostly non-existent in Houston.  For instance, the White Oak Bayou River watershed, which covers much of northwest Houston, has lost 70% of its wetlands since 1992.  The Dutch concept of “room for the river” – leaving floodplain zones undeveloped – seems non-existent.  Ditto for the more local, dispersed measures such green roofs, detention ponds, etc.  Would such measures have prevented flooding?  Of course not.  But they may well have reduced its extent.  As it is, Houston is in a low lying floodplain, but its culture – developers, city hall, citizens – seems to be one of denial.  This city, the fourth largest in the U.S., is also the largest that has no zoning regulations.

And it’s not as if it could not be foreseen.  Over a year ago, it was pointed out that “Houston is a sitting duck”, with respect to hurricanes and flooding.

It is also worth pointing out that the pollution that may result from the flooding is worrisome.  It’s not just the usual overflowing sewage: Houston is home to the largest petrochemical complex in the country, with 27 refineries, with 29% of the refining capacity and over 40% of the petrochemical industry located there.  All of this is at risk, and there are reports, possibly exaggerated, of “unbearable” petrochemical smells – air pollution is also a risk to be considered.

Aside from pollution, there is also all the risk to the transportation infrastructure.  Some roads and streets may not be able to support traffic if the wet soil risks caving in; same for bridge pilings.  It will a long time until buses run, to say nothing of being back to normal.

What Toronto would look like under Harvey

That leaves two big questions to contemplate.  The first one is, obviously, what would be impacts of such a storm at home?  The Weather Channel has an amusing map of what a storm like this would do to Toronto.  Not to worry: Toronto is unlikely to ever be in the path of such a hurricane.  Same for Vancouver.  But the underlying implication is: are we at all prepared for an unexpected storm?  Are we, like Houston, sitting ducks?  The recent flooding in Toronto or in Calgary probably means that the answer is yes.

The other big question is fundamental: how come?  What happened to led to this? Columnist George Monbiot points an accusing finger at the capitalist system.  Too pat, you’ll say; but, even if I disagree with it, it’s well worth reading and pondering.

__________________________________________________________________________

Postscript: of course, news keep coming fast.  IFLS has a good recap, and shared a remarkable visualization, from Vox,  of how much water we’re talking about (roughly four times what fell during Katrina).  Here it is, bellow.

 

Written by enviropaul

August 29, 2017 at 2:50 pm

Logical fallacies and the environment: correlation and causation

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Last year I published a series about logical fallacies that abound in pronouncements about environmental issues (here is an installment, as an example).  But I recently came across one of the best examples that illustrate how correlation and causation are distinct.

The example comes from the recent book by Anurag Agrawal, a world authority on monarchs.  Monarch numbers are clearly in decline, but what is causing it?  There are multiple causes, as always.  One possible cause that has often been pointed at is the use of GM corn and soybeans.  These plants are resistent to herbicides such as Roundup (glyphosate), and therefore much more of the herbicide has been sprayed as before.  If the drifting herbicide is also killing milkweed, it would deprive monarchs of their food source (monarchs eat only milkweed – nothing else).  Could that be the main reason that monarchs are becoming rarer?

On page 236 of the book, Agrawal proposes a graph (reproduced below) that seems to indicate that this is the case.

The caption reads: a) correlation between the percentage of genetically modified, herbicide-tolerant corn and soybeans planted each year in the United States and the monarch overwintering population size in Mexico, and b) the number of cell phone subscriptions in the United States and the same estimate of monarch populations.  Each point represents a year (1993-2014).  Note that the points are not in chronological order.

The top graph seems to strongly indict the GM plants, doesn’t it?  But wait, the bottom graph shows that maybe radiation from cell phones is to blame.  This is not as farfetched as it may originally seem: we still don’t know exactly how monarchs orient themselves for their yearly migration to mexico, and it is conceivable that the EMF from the now cell phones and towers is affecting their ability to navigate using the magnetic field.

But if the monarch decline is plotted against the S&P January stock market values, we get as strong a correlation – what is going on?  The reality is that all three correlations are very strong because the percent of GMO plantations, the number of cell phones, and the stock market have all increased over the time period under consideration, while the monarch numbers have consistently declined.  Agrawal states clearly that the correlations, in themselves, are not an indication of what is causing the decline.  (He also indicates that this doesn’t get the GM crops off the hook, either – merely that causation and correlation are different.  Saying that the fact that this is a mere correlation shows that GM crops are innocent would be equally spurious, a case of either-or fallacy).

The book is full of little gems like this, and I thoroughly enjoyed it – I recommend it to anyone interested in ecology.  If time permits, I will try to post a true review.  But meanwhile, for completeness sake, in case anyone doubts that monarch numbers are declining, here’s the data (from page 214):

We do have a bit of a crisis on our hands, when it comes to the monarch.  But thankfully, this is not the main theme of the book; co-evolution, with all its mysteries and wonders, is what the book is about, and it is written in a very accessible style.  Meanwhile, though, here’s the key lesson: one can really easily find correlations by plotting against one another the Y-axis of time series that have strong time trends.  And quite likely, just as easily can you use it to convince folks that you’ve found the environmental culprit!  But don’t.

 

 

Agrawal, Anurag 2017.  Monarchs and milkweeds: a migrating butterfly, a poisonous plant, and their remarkable story of coevolution.  Princeton U Press.

Written by enviropaul

August 11, 2017 at 12:02 pm

Electric cars and the Formula E race

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Yup, those are electric cars

Last weekend Montreal hosted the Formula E grand prix: a car race, similar to a Formula One, except that all cars are electric.  It has been popular, if controversial.  If you call yourself an environmentalist, do you cheer such races, or boo them?

For engineers and other geeks, there’s a lot to like about the event.  This is where electric mobility is put to the ultimate test.  Despite the fact that the cars are restricted in top speed (225 km/h) and maximum power ( 170 kW, equivalent to 225 horsepower), there is still plenty to work on.

Electric cars have batteries, which much get recharged; this is done using a converted diesel generator that runs on glycerin, a by-product from bio-diesel production that burns cleanly and is carbon neutral.  (Glycerin is also a feedstock of choice for biogas generators.)

The cars typically have a single engine, and – atypically for electric cars – a gearbox to optimize power regime; innovations such as torque vectoring (giving more power to the outside wheels during a turn) are forbidden.  A unique energy boost of 100 kilojoules is granted to three drivers selected by fans.  And then there are all sorts of technical tweaks beloved of fans, for getting more power and more efficiency out of things such as software power control, regenerative braking, battery thermal load management, and the like.

Many of the innovations tested on Formula E circuits end up in production cars.  Jaguar, for instance, which fielded cars last weekend, uses the platform to test and improve the performance of its I-Pace system  that powers its brand new all-electric SUV.  Says  Alain Leynaert, product planning manager for Jaguar

The I-Pace is sharing the same electric motor technology as the race cars. We’ve been asked why aren’t we using the same motor as Tesla. From our perspective, what we’ve seen is there are packaging and thermal benefits to the permanent magnet motor so we’ve decided to go that route.

This racing is really the most extreme testing you can ask for. What we see happening in the road car is just a snap shot of the extremes that the race car goes through. If we can manage to make the race car run well and be thermally reliable, it translates right into the passenger vehicle.

These are some of the benefits of this type of events: better electric vehicles.  Another set of benefits is public awareness: there are still many people who look at electric cars as glorified golf carts.  They are anything but, obviously; yet the two share something that fossil-fueled race cars don’t have: they are remarkably quiet, and they are pollution free.  This is why the races are held in an urban setting (downtown Montreal in this case): to show that, aside from the controversial road closures, there is little impact.  And this race had plenty of drama: there was a spectacular crash during the qualifying rounds as the current title holder, Sebastien Buemi  of Renault, crashed into a wall at high speed.  The car was repaired but eventually disqualified for being underweight.

So, overall, a good show, heralding the coming of the electric car.  Some people still poo-poo it (witness car commentator Motormouth here); others praise it.

Some of the commentary cautioning against widespread electric car adoption claim that it simply displaces pollution.  If the local electric power is produced by coal, isn’t that actually worse?  Well, no, it isn’t.  It may be in terms of ordinary air pollutants such as nitrogen oxides, if coal power plants are not equipped with pollution control devices as good as cars.  But this isn’t really the main point: rather, it’s about greenhouses gases.  According to some (such as Luc Vallée and Jean Michaud), it may actually be worse for the environment if coal is burned to make the electricity used in e-cars.  But this is a canard; an electric car is so efficient at converting electricity into motion that, even fuelled by coal-generated electricity, the production of carbon dioxide is still much lower than that of a similar gasoline or diesel vehicle.  That is because an electric car can convert over 90% of its electric charge into motion; an internal combustion car, only 20% at best (that’s why the radiator gets so hot: most of the energy disappears as heat).  In contrast, large coal (or natural gas) power plants have an efficiency of about 40%.  You can do the math: a combination electric car/coal plant is still twice as efficient as a gasoline car, and so emits only half the carbon dioxide for the same trip.  Unfortunately even Globe columnist Eric Reguly, who should know better, has fallen for that nonsense.

A better question may be: what would happen if all cars were replaced by electric cars?  Would that not strain the grid to the point of failure?  That is the line followed by proponents of big new projects, from Site C to the UK’s proposed Point Hinckley nuclear plant, a costly and unnecessary boondoggle if ever there was one.  Without question, this would indeed represent an additional demand to the system.  Ryan Carlyle calculated that, should all cars in the US turn into electric vehicles at the stroke of midnight, the electricity demand would increase by 29%.  (He also calculated that, with the current mix of power generation in the US, carbon dioxide generation would be reduced by 6% – so there, Reguly, Michaud and company.)

So an environmentalist may rejoice at the (smallish) reduction in CO2 emissions that electric cars represent, but blanch at the prospect of environmentally destructive megaprojects to boost electricity generation.  And it’s not just cars: much of our land transport, road and rail, could conceivably be fuelled by electricity, to say nothing of space and water heating, and many other uses of electricity that could replace fossil fuels and reduce greenhouse gas emissions.  Electric utilities have been considering this to justify forecasts of huge future demand increases.  They have a record of consistently over-predicting future demand ever since the 50s – but could they be right this time?

Not so fast, though – there are several trends and technical developments to consider, which complicate the situation considerably.  The first of these points is dispatchability, that is, the ability to generate electricity at the time when it is needed.   But cars do not typically consume power during peak demand times; power is needed when batteries get recharged, and this takes place most of the time at night, when demand is lowest.  Recharging a big fleet of electric vehicles may actually stabilize the grid; while more electrical energy would be consumed, the power capacity of the system would not need to increase, in this scenario.  That is because the power plants that we currently run have more than enough capacity to meet the recharging demand during off-peak hours.

The second trend to consider is increased efficiency.  Take lighting, for instance: the same brightness can be achieved with LEDs as with incandescent bulbs using less than 10% of the electricity required by the traditional bulbs.  The same is true for a variety of machinery, from electric motors to air-conditioners, computers to televisions, or data acquisition and control systems.  As technological breakthroughs keep happening, the overall demand for electricity of western societies is expected to drop.  So even if electric vehicles create an additional demand, that demand may well be canceled by efficiency gains elsewhere in the system.

The third trend that matters is the nature of electricity generation, itself, which is becoming decentralized.  Wind and solar power may be intermittent, but decentralized generation with matching storage means that grids are becoming much more robust than previously, not the other way around; the best test of this was the solar eclipse that occurred in Europe last year.  Many pundits expected black-outs and brown-outs from all the solar collectors going suddenly off-line, especially in countries heavily solarized like Germany; but the eclipse came and went without any hitch.  In practice, this could be as simple as charging a car at home using electricity from one’s own solar panels and batteries.

But most important is the trend away from cars.  A much smaller proportion of young people own cars or even have a driver’s license than a generation ago.  This is thought to be the result of a combination of factors, from a diminished value as status symbol (electronic gadgets replacing them) to improved transit and car-sharing.  As Eric Doherty eloquently describes, car-oriented projects that a few decades ago seemed fine are now considered absurd, such as the proposed ten-lane bridge over the Fraser.

So the demand for private cars is waning; and the demand for gas guzzlers is definitely dropping, with an end in sight.  Evans-Pritchard writes in the National Post that

OPEC and Big Oil thought they had 50 years. At best they have a decade…Just like what happened to Kodak when digital cameras appeared — the end will be swift and brutal.

So private cars may be on the way out, and that means less congestion, less noise, and fewer accidents.  But even so, the private car is not likely to disappear any time soon, if ever.  Tesla, now the darling of investors, has just announced the launch of its cheaper Model 3; there are already half a million customers who have plunked down a deposit to secure one.  China is now the biggest market for, and producer of, electric cars.  Germany plans to have one million electric cars on the road by 2020.  Electric cars already make up 40% of all cars sold in Norway.  The Nordic country, along with the Netherlands, will ban sales of fossil fuel cars by 2025; France and the UK plan to follow later.  Mining investors recognize that the demand for electric vehicles is already affecting the price of metals, particularly lithium and cobalt, but also aluminum, lead, and copper.   Shell’s CEO, Ben Van Beurden, has announced that his next car will be an electric one.  Electric cars are coming, like it or not.

I’m not much into car culture.  But if ever Formula E comes to Vancouver, I’ll enjoy the show.  With a clear conscience.

Written by enviropaul

August 5, 2017 at 5:06 pm

Dispatchability…uh, what?

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The emninetly dispatchable power of Dinorwig, a former quarry in Wales turned hydraulic storage

Today (8/8/17) SFU’s Mark Jaccard chimed in on the Site C debate with an opinion piece in the Vancouver Sun about dispatchability. Huh?

What appears to irritate Jaccard, a highly influential scholar and environmentalist, is the often repeated claim that while the costs of Site C keep climbing, those of renewables keep dropping.  By the time the Site C dam is completed, wind and solar will be so cheap that BC will be saddled with a white elephant.  Not so fast, says Jaccard: the real comparison should made on the cost of dispatchable electricity, not simply the price per kilowatt of capacity, nor that of produced electricity in kilowatt-hours.  Rather, what matters is the cost of producing electricity at the time when it is needed.  For instance, wind electricity that is only produced at nighttime, when no-one needs it, would indeed have indeed very low value; conversely, wind that reliably produces electricity at peak times (typically late afternoon), would be worth much more.  Dispatchable electricity, that is, electricity that can be matched to the demand, is indeed much more valuable.

Jaccard should be applauded for introducing this fairly arcane concept into the discussion.  As the Utilities Commission, which is finally reviewing Site C, drafts its recommendations, the concept of dispatchability is likely to get more airplay – and generate further confusion.  Forewarned…

That said, I expect this editorial to be embraced by the defenders of Site C.  Jaccard, wisely, does not pronounce himself on the issue.

That may be because, ultimately, dispatchability is unlikely to be a key issue.  Jaccard mentions that a large reservoir, such as would be created by Site C, does  provide dispatchability because of its ability to store water and release it only as needed.  A large hydro-electric reservoir is an ideal match for an intermittent source such as wind or solar.  Indeed, according to Jaccard,

As we invest in more wind and solar, the economics of dispatchable sources like Site C improves.

This is counter-intuitive, but true – in general.  But this is very unlikely to be true of Site C, itself.  This is because Site C would create just another reservoir, one among many in the province.  Site A, where the WAC Bennett was built, is a case in point: it created Williston Lake, a reservoir that dwarfs the proposed reservoir that Site C would create in the Peace valley.  And there are many more, of course: just think of Kootenay Lake or the Arrow Lakes to get an idea of the storage capacity we already have.  We are already well equipped to partner with any increase in intermittent power such as wind or solar.

Jaccard also mentions that other energy storage options, such as batteries, are much more costly than its equivalent capacity in a large hydroelectric reservoir.  But this is the same refrain as was said last decade about wind and solar: too expensive.  As larger and larger storage systems come on line (such as  the newly announced projects in Hawaii and Australia), unit costs per unit power are going to drop, just as they did for solar, because of the economies of scale in manufacturing, as well as new technical developments.  True, we’re not there yet, but there is no reason to expect that batteries would not follow a price curve similar to solar cells or computers.  In contrast, if Muskrat Falls is any indication, the price of Site C is going to keep soaring skywards.  I have not asked him, but my guess is that Jaccard’s prudence and lack of commitment on this issue comes from the fact that he knows these facts, just like Andrew Weaver does.  And like Weaver, I expect Jaccard to eventually admit, sooner or later, that Site C is unnecessary.

But if nothing else, Jaccard has the merit of introducing the concept of dispatchability to the general public, at least to those who read the papers.  If it becomes a household word, I fully expect the geothermal energy folks to start trumpeting: “Hey, we’re dispatchable! Invest with us!”

And a good thing that would be.

Written by enviropaul

August 4, 2017 at 3:40 pm

Water and the Canadian identity

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From Renzetti`s Globe and mail article

Last Canada Day, Elizabeth Renzetti, the Globe & Mail columnist, chose to highlight water: the attachment that we, Canadians, have for it.  Water is everywhere in Canadians’ lives, from canoeing to showering; we take water for granted (and waste a lot of it); and, more than others, we are blind to our water issues.  A piece well worth reading (link here).

From the paintings of the Group of Seven to our tourist brochures, water is everywhere in our collective imagination and it binds us.  Renzetti describes

the mundane magic of a Canadian landscape: a gorgeous, fast-flowing body of water, surrounded by trees and flowers and birds. A group of men sat on rocks in the middle, speaking a language I didn’t recognize. A young couple had hauled their infant in its stroller down the trail and dipped the smiling baby into the water, a Canadian baptism. My children stopped complaining. We all sat with our feet in the creek, strangers united by this water.

This is one way to think of Canada: We are strangers united by water. Oceans surround us on three sides, at least a quarter of a million rivers flow in all directions.

Renzetti has an insight on water that few of us have: a brother, Steven, who was an expert on water.  He unfortunately died this February, a big loss for his family, of course, but also for the university where he worked (Brock) and for the community of water thinkers across the country.  A sample of his thinking can be found in this 2010 Tyee article here.

And it is true that we have plenty of issues: while we use and waste more water than pretty much any other nation, we also pay too little attention to its safety (witness the Walkerton tragedy) and its quality.  Our waters are polluted.  This is especially true away from the big cities, especially in the North.  Though the North occupies a special place in our identity, Canadians are mostly ignorant of its everyday realities.  Quoting Renzetti  again:

We love water, we are drawn to it, but for years we have taken it for granted. Perhaps we’re not quite the guardians we hoped we’d be. We may be on the verge of paying the price.

A recent report from the World Wildlife Fund found that a number of the country’s watersheds were threatened by pollution and habitat loss – and the problem could be worse than we know, since data-gathering is so poor. Across the country, Indigenous communities endure water that is not safe to drink, with some water advisories lasting for years.

We don’t know enough about water in this country. We consume too much. We’re the second-highest per-capita consumers of water in the world! We don’t charge enough for it. We don’t think enough about it, because it’s everywhere. One day the well might run dry, when we are looking the other way.

“Looking the other way”, “data gathering is so poor”.  Indeed.  What was already a poor situation in the 90s was made worse under the government of Stephen Harper, with cutbacks affecting data gathering on water quality, a situation that has not been rectified yet by the current government.  Regulation is no better; just the week, the government announced it was giving the okay to gold miner Seabridge to dump tailings in fish bearings streams of the Nass River watershed.

First Nations, of course, also have a special relationship with water (see Honoring Water here, or Indigenous Perspectives here).  But a special relationship to water is true of all Canadians, and that expresses itself in our fine art production, which abundantly features water, but also in our folklore.

Think, for instance, of two of the best known (and best loved) folk songs of this land, the Log Driver’s Waltz and the Blackfly Song, both by Wade Hemsworth.  Blackflies lay their eggs on running waters, so it makes sense that they would torment a surveyor working on a project to dam a river, the Little Abitibi.  As for the log driver, if you don’t get the importance of water, you weren’t paying attention.  Enjoy!

 

 

Written by enviropaul

July 21, 2017 at 5:34 pm

The Montréal flood of 1987

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Thirty years ago, there was a huge cloudburst that paralyzed the city.  Ici Radio-Canada has put some video footage on-line, and it’s quite interesting.  It’s in French, of course, but the images are quite eloquent.  Here is a link to the article that features the video; the translation is from me.

The Décarie Expressway, thirty years ago.

The city had been under a heat wave, and when a cold front came a huge storm was created: over 100 millimetres of rain fell in an hour. A storekeeper witnessed the storm:

The wind started blowing, and all of a sudden you couldn’t see anything, it was like white smoke.  But it was rain! Trees were all bent.  Water started coming here through the roof, through the windows, even through the toilet.  We have three feet of water in the basement!

Weatherman Pascal Yiakouvakis explained that there was wind, rain and hail.  For hail to form, the storm cloud has to be very tall, at least ten kilometers – one can imagine how much water that represents!  More water fell in one hour (100 mm) than normally falls in an average July in Montréal (90 mm)  That is also much more than the stormdrains can handle: their design capacity is for 40 mm/hr.

Traffic was paralyzed, even emergency vehicles could not move.  Drivers had to be rescued, using ladders, from the below-ground level highways like the Décarie Expressway.  Hydro Québec reported a loss of power to about 350,000 households, without knowing exactly where: the storm had damaged the main computerized data control system.  The Montréal Métro had to shut down, the tunnels were completely flooded.

In the wake of the flooding of Gatineau, Rigaud, and areas around Montréal this past spring, one wonders what, if anything, has been learned.  The two instances of flooding cannot be compared, of course; the 1987 flood was a local cloudburst (Longueuil, on the south shore, got barely 10 mm during the storm) of short duration, while this year’s flooding was due to relentless rain over a large area for over a month.

But still, would it not be a good idea to berm the subway entrances so that flooding is minimized? The same scenario happened in New York City after the storm Sandy, and this is something considered. Does it make sense to put a highly in a large ditch?  Not really – actually, any highway is a long scar through a neighbourhood, and it traps users whenever something goes wrong.  Surface streets with regular intersections are far more resilient.

Does the engineering approach of stormdrains work?  Yes, it does, but it has its limitations.  Whether a system can drain floods according to its design specs depends on maintenance, among other things; today (July 15th) CBC reported about a flood in a Montréal underpass because sand and gravel had accumulated in the combined sewer pipe.

But even should the system work as designed, the design criteria are no match for a storm from hell.  Green roofs can shave off a few millimeters from a storm, preventing the worst; cities as diverse as Chicago and Paris have now mandated them on new construction. Ditto for infiltration basins and rain gardens; we are starting to see these here and there (for instance, nearby Township of Langley has some interesting plans).  And our combined sewers could do with expanded storage: much larger pipes can be used in strategic locations, creating underground reservoirs that let sewage flow freely but can store storm waters when necessary (and also prevent release of combined sewage and strom waters, or CSOs; that`s their key design function).

But to find really aggressive approaches, one has to look overseas – and nowhere better than the Netherlands.  Rotterdam, for instance, has created a good number of, well, holes under the ground surface, where cloudburst water can accumulate before flooding streets and houses.  For instance, the underground parking lot of the biggest art museum in town (Boijmans van Beuningen) is designed to flood automatically under cloudburst conditions.  In another instance, a local school has a sunken outdoor basketball court; as much as two meters of rain can gather there.

Vancouver has at least one large tunnel, abandonned and condemned, that could serve as a temporary receptacle for deluge-like storm waters.  I expect this is also true in Montréal as in many Canadian cities that have been flooded in the last decade.  But I rarely hear anything like that mentioned.  How about you, Calgary?  Toronto?  …anyone?

 

Written by enviropaul

July 15, 2017 at 5:23 pm