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Musings about the environment and all it touches, from education to city planning

Archive for October 2015

Weird architecture: the unique Villa E96

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Who says an envirohouse has to look boring? That must have been the reaction of architect Heinrich Stöter. His Villa E96, on tony Elbchaussee, has become an eye-catching landmark.

The building features an array of solar thermal collectors in the façade, arranged in a seemingly random fashion; solar PV on the roof; rain water collection; heat recovery ventilation; and durable, naturally sourced construction materials. Impressive environmental creds, especially considering the house was built in 1996.IMG_8038

The whimsical 800 m2 creation – dubbed “poetic high-tech baroque” by its creator – is used as an art gallery and a venue for special events. But above all, it is an architecture statement. “This approach gives us an insight into the ecological buildings of the future”, says the creator, “we use the most modern technology available in order to live in an environmentally-conscious fashion”. Money was no object, either; at 2600 deutsche marks per square meter, the building costs were double that of a standard luxury building at the time.

IMG_8036Say what you will about it, it is daring. What impresses me most, though, is that after nearly two decades it still looks new; chalk it to quality design or quality materials, it has stood the test of time.  Weird, maybe, but making a case for sustainability – at least in high end construction.

Details (in German) can be found here, here and here.

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Written by enviropaul

October 27, 2015 at 8:53 am

Bergedorf and its university

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Bergedorf

Bergedorf

On Friday I visited the neighbourhood of Bergedorf, home of one of the campuses of HAW, Hamburg University of Applied Sciences. It reminded me a bit of my situation in Langley: an applied technology program in a satellite campus in a far-flung suburb.

The comparisons stop there, though. HAW is a full-fledged university with post-graduate degrees, and Bergedorf has a pedestrian town centre and a sixteenth century castle. And it is easily accessible from downtown by commuter train. But despite the differences, it may have lessons for Kwantlen.

I met with professor Heiner Kühle, the director of the Environmental Technology program. We chatted about our respective programs: his department offers bachelor’s and master’s programs in environmental assessments and in renewable energy technologies. At the bachelor’s level, all students must complete a semester working in the industry. Students do this in their senior year, and are expected to work “just as if they were junior engineers” to use Dr Kühle’s words. I asked whether there are ever issues of work-terms not measuring up to expectations, in terms of learning experience for the students. Dr Kühle replied that, while it is a concern, in practice such problems don’t happen. That is because faculty and employers tend to work closely together; faculty members often perform research in partnership with the employers, so the school knows well what the student’s experience consists of.

Professor Heiner Kühle

Professor Heiner Kühle

Conversely, students are rarely directly involved in such research; there is no curricular requirements for them to conduct a research project. I was left with the impression that this is a far better model than ours in Canada. While being involved in a research project does have its advantages and learning outcomes (a student has to integrate material, learns to plan, etc), often undergraduates lack the necessary depth of knowledge to carry out a meaningful project. Instead, a work placement at the right technical level is far more appropriate to prepare a student to thrive in the work place.

In fact, such placements are something that HAW fought to keep in its programs (other universities have cut theirs when asked by the government to shorten their programs). This may have something to do with the make up of the faculty. All instructors are required to have a minimum of five years of full-time experience in the industry, as well as having a PhD; Dr Kühle, a physicist by training, worked for several years on energy conservation projects before joining the faculty. So he and his colleagues keep an eye on the practical elements above all.

As at Kwantlen, the focus is on education and the instructors get to know their students well. This became quite apparent in the chatter between Dr Kühle and students as we made our way to the cafeteria (instructors share their eating space with the students). I asked him about the mix of research and teaching work. He answered that he is not required to do any research; the research he does is “for fun, and to keep current”. But since HAW is considered an applied science university – aka, a teaching university – his teaching load is higher: eighteen contact hours per week, as opposed to eight in a conventional university. These loads are mandated by government regulation.

This amount of teaching leaves time for research. Dr Kühle mentioned that he is currently analysing the performance of an energy retrofit for a daycare: an interesting problem as daycares are empty at night, and so winter heating requirements have a high morning peak before the body heat of the children takes over. (He also mentioned a project with Airbus: they have problems with their on-board sewage tanks sensors, which tell the plane that the tanks are full before they actually are – a foaming problem, apparently. Kühle said he enjoys challenges!)

The Bergedorf campus of HAW

The Bergedorf campus of HAW

Not that everything is rosy. The campus itself, built in 1974, is a charmless instance of brutalist architecture, and the building originally meant for 600 students now bursts at the seams with about 2000 of them. And the campus has little life: once classes are over, students all leave. Downtown Hamburg is within easy train reach (a mere ten minutes on the regional express!). Even though Bergedorf has its charms, most students live elsewhere, making it difficult to create a real identity for the campus.

This is particularly unfortunate since the university has a large contingent of foreign students, most at the masters level. I spoke with two students freshly arrived from India. They like their classes, but switching to German is a tall order (“we took two years of German classes in Bangalore, but somehow that’s not quite enough”). Indian students form a large contingent of the international group, partly because the program’s focus on solar energy, a booming sector in India, but also because of a well developed outreach effort over the years.

If these are problems for HAW, where does that leave Kwantlen in Langley? How do we compete on the world scene? We don’t offer Master’s programs, as yet. Our instructors teach exactly twice as many hours as HAW’s, leaving little time for research, or for innovative workplace integration, for instance. We offer little in terms of student housing support, and Langley has no charming pedestrian core, never mind ancient canals and a baroque era castle. Do we just give up?

I don’t think so. There’s a lot that we could offer. We have a pretty unique mix of innovative agriculture and horticulture, for instance, with classes as well as research opportunities. And our language is English, which helps. But just imagine what we could do if our post-secondary institutions were supported as in Germany: no tuition! More faculty to look after students, as well as carrying out research! If education is as important as politicans claim, with our knowledge economy and what have you…uh, how about a little more support.

As for Langley, well…there is potential for a pedestrian area in the downtown core, and great bike path opportunities. I won’t hold my breath, but that is the inevitable future. Why not be a pioneer?

The pedestrian area in the centre of town

The pedestrian area in the centre of town

Note: HAW offers some summer courses in English, aimed at the post-grad crowd but open to anyone interested. Applied limnology, sustainable energy economics, or toxicology are among the options, which change from year to year. Not a bad way to spend a summer.

Written by enviropaul

October 27, 2015 at 3:53 am

What if Canada voted German style?

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MMP 2015

Germans vote using something called Mixed Member Proportional, or MMP, as opposed to the First Past The Post (FPTP) approach used in Canada. Had we used their system, there would have been a minority government in these elections, as well as in 2011, as the table above shows. Smaller parties (the Greens and the Bloc Quebecois) would have had more representatives in Parliament.

To calculate these results, I used a simplified version of MMP. I took the number of members elected from each party (eg, 184 for the liberals), and then added to that number the result of multiplying the vote percentage by the total number of seats (eg, 39.5% of the vote for the liberals means 39.5% of the 338 seats, or 134). I divided the result by two so as to be able to compare directly between the two systems.

This is a simplified version of the MMP used in Germany, and also now in New Zealand (a more in-depth description of MMP can be found here and here). The Germans selected this system after the war as a compromise between the FPTP approach (which can be unfair when a party gets in power with fewer votes than its nearest rival) and the pure proportional system, which is what the pre-war Weimar republic used, and which led to government instability.

In Germany, with its long track record, the main impact of using MMP is that no party ever gets a full majority and governing coalitions need to be created. Now some canadians, used to FPTP, may blanch at this idea; compromising with the enemy is a betrayal of principles, isn’t it?

Germans don’t see it that way. After all, politics is the art of the possible, and compromise is not a dirty word. But the creativity that comes with a coalition of several parties means that the government can sometimes accomplish more than with a FPTP. Also, there is more respect for the work of the government – and that, despite the fact that Germans are famously cynical.

A poster for the Greens for the European parliament elections. "Europe, don't forget about the young!"

A poster for the Greens for the European parliament elections. “Europe, don’t forget your youth!”

For instance, it was a coalition government that created Germany’s Energiewende, the envied program that made the country a champion of renewable energy and energy conservation. Since the start of the program in 2000, Germany saw its economy grow while its carbon emissions have decreased, showing (for the first time) that decoupling economic growth from emissions is possible. How did that happen? Because of Germany’s MMP system, Greens first entered parliament in 1984 and, while a small presence, there was now a voice for environmental concerns. Step forward to 2000 and the Greens have enough seats to support the Social Democrats of Gerhard Schroeder, who promptly enacted the Renewable Energy Act which gave rise to the Energiewende.

Look at it a different way: we got medicare in Canada under a minority government: a de-facto coalition of Liberals and NDP. Using MMP would only foster more situations like these.

The Greens, the NDP, and belatedly the Liberals have all said that electoral reform is needed, so let’s hold them to it. And then we may see governments pass needed legislations, energiewende-style, as opposed to wasting time in partisan disputes. That is my fervent hope.

 

Written by enviropaul

October 20, 2015 at 4:35 pm

Book review: a force of nature

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ForceofNature hc final coverJust finished a book (thank you, VPL on-line collection) that was a most satisfying read. It’s one of these environmental books that make you feel there’s hope.

A pretty tall order, given that the book, Edward Humes’s Force of Nature, is about Wal-Mart and how the company’s management put the company on a sustainable path. Now this is hard to swallow if you’re any kind of environmental or social activist; Wal-Mart is the devil that has caused misery, created poverty, eviscerated downtowns, and so on.

Humes, a master of the telling anecdote, doesn’t gloss over Wal-Mart’s misdeeds, which is why the book is a bit of a tour de force when it comes to convincing the reader that the company is not only sincere, but effective. How it happened is remarkable, and it is as much the story of white-water rafter turned consultant Jib Ellison and his company Blu Skye, as it is that of Wal-Mart and his then CEO Lee Scott.

In fact, it is so interesting – and controversial – that I’ve been thinking of how to assign the book as class reading. The book embodies one of the best, easy to understand, and interesting overview of sustainability, its principles, problems and practical applications, that I’ve come across.

The process of how Wal-Mart got there is really interesting, and makes up the core of the book. But since the proof is in the pudding, I’ll quote some figures from the book:
• Carbon emissions from trucks, stores and other operations have gone from 60 tonnes per $1m in sales in 2005, to 50 in 2008
• The efficiency of the truck fleet has increased by 60% compared to 2005
• The stores recycle or reuse 64% of its garbage
• All personal computers abide by European standards, which are more stringent than North America’s
• All TVs sold in US and Japan are 67% more energy efficient than in 2008

A remarkable performance, especially given the company relentless pursuit of low prices; sustainability is seen as eliminating waste through the supply chain, with the belief that doing so pays for itself. As Humes puts it,

there’s no handbook for how Wal-Mart and Blu Skye set this sustainability quest in motion, but if there were, there would be a few simple rules:
• Start with the hire-fire guy: a company has to be sustainable from the top down
• Sustainability must be part of every employee’s mission; relegate it to its own department, and it will fail
• Waste = money
• Carbon = energy = money
• Burst the bubble: talk to activists and environmentalists, consider their criticisms and advice (it’s free)
• Green is what the next generation of consumers care about

Humes concludes, in the epilogue

Despite all the good works that Wal-Mart (and Nike and Procter & Gamble and others) have done on the environmental front, such corporations as we know them cannot be sustainable. Yet, paradoxically, the answer to another important question – has Wal-Mart led the business world toward a new age of sustainability? – is yes.

In fact, Humes is convincing enough in his book (he is the recipient of a Pulitzer, after all) that conservative reviewers took issue with the book as well as with Wal-Mart’s turn-around. For instance, Angela Logomasini, a fellow at the Competitive Enterprise, writes a scathing review with comments such as:

Never questioning the hype, Mr. Humes explains how Wal-Mart solicited the advice of green-product activist William McDonough, who urged the company to back away from supposed perilous products such as carpets backed by polyvinyl chloride (PVC), aka vinyl. Such carpet, Mr. McDonough told Wal-Mart executives, posed cancer risks and was too difficult to recycle. However, there is little proof that cancer is caused by trace exposures to chemicals found in vinyl…

To have the climate deniers and enviro-bashers thrash your book: that is high praise indeed! Read the book, and if you’re like me you’ll go from a skeptic to a convert. Do I love Wal-Mart now? Uh, no. But do I think that business and private enterprise can be part of the solution? With some caveats (Volkswagen comes to mind…), maybe, yeah.

Edward Humes, 2011. Force of Nature: the unlikely story of Wal-Mart’s green revolution and how it could transform business and save the world. Harper Collins.

Written by enviropaul

October 18, 2015 at 11:41 am

How do you recycle a bunker, part 2: the Heiligengeistfeld giant

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The Flakturm IV in a sea of concrete

The Flakturm IV in a sea of pavement

One of the traditional fun things to do in Hamburg is go to the Dom. This is a big cheesy fair held three times of year. I went there a few years ago (missed it this year!), rode the Ferris Wheel, and sampled a currywurst for the first time.

Currywurst at the Dom, 2011

Currywurst at the Dom, 2011

The site of the fair, Heiligengeistfeld, is named after the long gone Holy Ghost hospital. The 20 hectare field was used to grow food for the hospital as early as the fourteenth century. But now, with the fair gone, the site is desolate: it’s a large, flat paved area with nothing on it but a giant bunker, the old Flakturm IV. But the bunker may be at the core of re-greening the site: there is a proposal to build hanging gardens all over it.

The bunker is massive: each side is 75 meters long, the structure is 42 meters tall (about six storeys), and more than 80,000 cubic meters of concrete were used for the 3.5 meter thick walls and five meter thick roof. The whole thing, large enough to shelter 25,000 people during the worst air raid, was topped with four twin anti-aircraft cannons.

The Wilhelmsburg bunker a few years ago

The Wilhelmsburg bunker a few years ago

Project leader Robin Houcken, with a group of activists, wants to use the bunker as a focus for re-greening the area. “We got inspired by the overgrown Wilhelmsburg bunker”, he said. The formerly abandoned bunker had trees and weeds growing all over it: why not channel this image into a vision for a park?

The basis of the design is the creation of a pyramid atop the bunker. On the top level, a 1500 square meter garden will incorporate trees and areas for urban farming. The descending levels will also be planted, for a total of 1800 square meters. A ramp, vegetated as well, is to be built around the bunker for public access.

Inside the pyramid will be several rooms to host community amenities such as a library or a community kitchen, as well as small show rooms or even accommodation for touring artists. The main hall, already used periodically for technopop concerts and raves, will be renovated but still used for cultural events.

What Heiligengeist could become: the hanging gardens of hamburg

What Heiligengeist could become: the hanging gardens of hamburg

Of course, heritage values are key for a site like this. The structure of the bunker itself will not be modified.  The pyramid at the top will also include a memorial to the victims of war, including the thousand prisoners whose forced labour built the structure.

One of the remarkable aspects of the project has been the local community buy-in. From the very start, consultation and transparency were seen as key values. Anti-gentrification protests, usually so common in German cities, have not emerged here. Politicians have responded accordingly, and the project should get going in 2016. The greening will extend to parts of the parking lot, as well.

In that respect, the project website is remarkable in its thoroughness. Too bad it’s in German; I can appreciate only part of it. But I love daring projects, and this is one to follow.

Details of the design

Details of the design

Written by enviropaul

October 15, 2015 at 11:52 am

How Germany gets it done (it’s about climate)

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The market for solar power didn't happen by itself; incentives created it.

The market for solar power didn’t happen by itself; incentives created it.

I’m making my way through the German Government’s Climate Action Programme 2020.

Yawn. Thank God it’s in English. But despite the impression conveyed by the ponderous title, it’s actually not bad reading at all, because – contrary to what I have come to expect from my governments, being Canadian – this document has actual substance and specifics.

Here’s an example: “In view of the growing heat efficiency of the buildings, the use of fuel cells with a high electricity to heat ratio is becoming an increasingly attractive option.

Whoa, what was that? Fuel cells? The high tech thingies that were developed in Vancouver by Ballard ages ago? The Germans plan to introduce “a funding criterion for particularly electricity-efficient systems (fuel cells)”.

Let’s back up a bit. What does that mean?

The German government created a whole program for combined heat and power systems (CHP), including micro CHP that can be used in the residential sector. The logic goes as follows: if you’re are going to burn natural gas (or some other fuel) to heat up your building, why not also produce electricity? Instead of using a furnace, use an engine; most of the energy of the fuel turns into heat, anyways. So instead of using a radiator to get rid of the heat, as in a car, connect the hot pipes to the heating system, et voila: same heat as with a furnace, but electricity that is sold to the grid.

These systems have become fairly popular (an example of such a system for a small home can be seen here), since the government provides incentives for them while discouraging the installation of inefficient heating systems. But there is a problem: most of the energy is still dissipated as heat, and a well insulated house or apartment building doesn’t need much heat. So installing a CHP may be costly if you don’t need much heat.

As a result, the government is now considering the next logical step: creating incentives for fuel cells, because of their increased efficiency.

How a fuel cell works (and Ballard's works fine!)

How a fuel cell works (and Ballard’s works fine!)

Maybe it’s foolish: fuel cells are expensive, complex, and not quite ready for the domestic market. But the very same thing was said about photovoltaic solar panels twenty years ago. The government of the time created incentives in the form of guaranteed feed-in tariffs, and the market took off, with the result that solar cells are much cheaper now, and their price continues to drop. If the government is serious about creating a demand for solar cells, watch out.

Meanwhile, in Canada, we’re a long way away from having these problems. We don’t have domestic CHP; nobody would buy it. Not only are there no incentives, but getting the grid to purchase the power is difficult.

The same thing can be said about fuel cells. Despite a promising start in Vancouver (there was a time when stock brokers were all pushing Ballard Power) the innovation has be let to wither on the vine. Oh, it’s not dead altogether; there have been some contracts for stationary sites, and demonstration projects like the hydrogen fuel cell buses that ran between Vancouver and Whistler, a project since cancelled.

This is the essential difference between the R&D strategy between the two countries. Both believe in the efficiency of the market. But in Canada, once a new technology has been developed, it is left to fend for itself and often dies; we say, well, that’s the market’s decision, it must be right. Fuels cells have been invented here; the technology for PassivHaus was invented here. But it never took off.

In Germany, by contrast, the Government has a clear vision of what it wants (to combat climate change, to create employment, whatever) but accomplishes it by creating a need: a market. It felt confident that through a feed-in tariff, it would create a market for solar panels. It knew that by enacting energy efficiency requirements, it would create a market for homes built on the PassivHaus standard. The same may well apply to fuel cells, and once again we may see a Canadian-born technology flourish in Germany.

It’s not rocket science. Governments create incentives. Incentives create markets. Markets foster innovation, efficiency – and jobs.

In this country we don’t do that, out of a misplaced belief that markets should never be messed with. But markets need a first kick to get going; once there, sure, don’t mess. But get them started, for crying out loud! There’s no hope of tackling climate change otherwise; but also, there no hope of creating jobs – it’s that simple.

Written by enviropaul

October 14, 2015 at 8:57 am

Ottensen, or how to improve the environmental performance of a heritage district

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Ottensen's main street

Ottensen’s main street

Cities offer the best hope for tackling climate change. New dense developments with energy efficient buildings and short commutes with good public transit, such as Hamburg’s HafenCity, show how it can be done. That’s all well and good, but what about established neighbourhoods? Can their environmental performance be improved without destroying the character that makes them so compelling? I went for a walk in Ottensen to see how Hamburg’s climate initiatives apply in such cases.

Ottensen has the highest population density of all neighbourhoods in Hamburg. It survived the war relatively unscathed, so much of its housing stock, four-story appartments, predates the twentieth century. Until recently a working-class area, it is now highly desirable, with narrow winding streets that lead to the Elbe beach. But it has escaped the worse of gentrification, as it still has some affordable housing, a well integrated immigrant community, even graffiti. But the needs are clear: more housing, and a better environmental performance, is needed. How do you “improve” such an area without ruining it?

I took a look at Bergiusstrasse 24, a 10-appartment complex built in 1994, that the city promotes as a example. At over twenty years of age, the façade of brick building is fully covered in ivy and fits well in its surroundings; you wouldn’t know there’s anything special about this building. But its performance is remarkable: old as it is, it still requires no more than 41 kWh of energy per year per square meter of floor. This is 44% less than the adjacent buildings built during the same time period, and not even a quarter of what older buildings consume.

Bergiusstrasse

Bergiusstrasse.  Number 24 is the one with the ivy (and the “nuclear? no thank you” flags)

The building is heated with natural gas, but there are also 34 m2 of solar collectors on the roof, which supply all of the hot water needs during the summer. Also on the roof is a 20 m3 rainwater tank that provides water for toilet flushing and the communal laundry, leaving enough for the garden in the inner courtyard.

The building relies on think insulation to achieve its environmental performance; back in 1994, using a ventilation heat exchanger was considered a risky, newfangled approach. Instead, residents were asked to keep windows closed as much as possible during the winter; this originally created a huge controversy, to the extent that some of of the original community participants quit the project. As a Canadian, I did a double-take upon learning this, because this is second nature and the request seems so straightforward. But many Germans are used to sleeping with the windows partially open, to let in frische luft.

Resident Monika Bauer, an architect, says: “this turned out to be much ado about nothing. Sure, there are no tilting windows, and windows can’t remain open in winter; but that’s not to say that they can’t be opened to freshen up the air every now and then. I find that letting the thermostat control the temperature, leaving it alone, works best; the rooms are comfortable, and because of the insulation the walls feel warm.”

There are other examples of projects throughout the neighbourhood. Most put priority on housing needs, but renovations mean that better insulation can be incorporated along with the other features. For instance, Kastanienhof, a complex of old buildings on Grosse Rainstrasse 13, has been modernized so that the historic character (and the chestnut trees that give it its name) remains intact; but green roofs have been integrated to the complex.

The courtyard of Kastanienhof: can you tell that this has been renovated?

The courtyard of Kastanienhof: can you tell that this has just been renovated?

Many of these old complexes have an inner courtyard, often smallish and used for parking cars. This presents an opportunity, as in the case of Fette-Höfe, on Spritzenplatz 5. This is a group of old buildings, some with a lovely Jugendstil, or Art Nouveau, façade, facing a small square that hosted a farmer’s market when I visited. In this complex 23 new units were added to the inner court, along with two playgrounds, in 2013. All the new appartments are handicapped-accessible and can accommodate various needs, an important feature since Germany’s population is aging. The additions are a mixture of residential (2850 m2) and work environments (3100 m2), including the small Uli-Cami mosque. The city considers this sort of mix a key to sustainability: by mixing working and residential spaces, commuting is reduced and the mix contributes to the variety and liveability of the neighbourhood.

The roofs of the additions in the Fette-Höfe complex represent large flat surfaces, making it practical to incorporate green roofs in the form of terrasses accessible to the residents. Green roofs are key in such dense neighbourhoods; not only do they contribute to insulate the buildings, they also reduce air pollutants and, mostly, absorb excess rain. Old, dense neighbourhoods are particularly vulnerable to flooding following extreme storms, and pervious surfaces, such as green roofs, help.

farmer's market in front of Fette-Hoefe

Farmer’s market in front of Fette-Hoefe

But it’s not as if the neighbourhood has no green spaces. One of my favourite urban parks there is on Kemal-Altun-Platz, a 0.6 hectare multi-use park on the site of a former factory, Menck&Hambrock. The company used to make backhoes and excavators and had a large presence in Ottensen, with 2000 employees, so the park has an important heritage role. This is outlined in one of the landscaping details: the central play area is shaped like a set of cogwheels, and the park designers placed an old steam excavator near the entrance.

It’s a nice touch, but that’s not why the park is so appealing; rather, what is remarkable is how such a relatively small area can be such an efficient multi-use space. When I visited, there were toddlers playing in an area enclosed by wild-looking bushes, while older kids were helping themselves to a pile of old wood to build a bonfire, apparently unsupervised. There were kids running around and laughing, engaged in what to me look like a completely unstructured game of sorts. Somehow, there was a sense of unrestrained creative play and untamed nature that one would expect in the countryside, not in a small urban park. But despite that – the kids’ area occupies maybe just 150 square meters – the park has room for a playing field, a wall for graffiti, a separate dog area, and a liegewiese, a concept beloved of the Germans: a lawn intended specifically for sun-tanning or just plain lying around.

Does this have any lessons that would apply to Vancouver? At first glance, maybe not, because Vancouver lacks this type of dense, old and established neighbourhood. But then again, it brings to mind Gastown and Yaletown, or downtown New Westminster, or downtown Victoria, where this approach (green roofs and insulation retrofit, repurposed use of historical buildings, community-based decisions) could be adapted nicely.

Kids building a bonfire in Park

Kids building a bonfire in Kemal-Altun-Platz Park

Note: more details, and similar examples, can be found in city documents such as Future, Sustainable and Ecological (in German), Quality Housing Projects (in German), and Hamburg Green Spaces (in English, surprisingly), all downloadable as pdf.

Written by enviropaul

October 9, 2015 at 7:17 am