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Archive for February 2018

A courtyard in Ottensen

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The inner courtyard, safe for kids and cats

Hamburg has a lot of green space, even though they can’t always be seen from the street: they are in the inner courtyards.  These courtyards are a fabulous amenity, providing an antidote to urban issues: they offer quiet, green, safe spaces.

Hamburg is particularly fortunate in that respect.  Not all courtyards are great; Hamburg learned from Berlin’s experience.  In Berlin the buildings are taller and the courtyards narrower, so that they are permanently shaded, particularly dreary in winter.  In Berlin the apartment buildings of the inner city were built fast to accommodate an unprecedented migration from the countryside between 1850 and 1900.  They came to be called mietskaserne, the hovels of the poor sketched by Zille or Kollwitz, built without lawns or green space, “the dark, infested, despised Hinterhöfe – the tenement blocks – of Berlin”, to quote Alexandra Richie, who documents details such as there being only one toilet, out in the courtyard, emptying into a cesspit, for every ten flats.

Hamburg was never as big a draw as Berlin, and city planners, Fritz Schumacher among them, had a chance to reflect on Berlin’s experience; they decreed that inner courtyards needed to be sufficiently large to let in sunlight and allow for good air circulation.  As a result, many of the Hamburg buildings built in the 1900-1920 period have grassy courtyards with large old trees.

I had a chance to experience that for myself.  During one of our visits to our friends Stephan and Anya, I asked if we could go into the courtyard of their building.  Their building is one of many contiguous apartment blocks on Friedensallee in Ottensen, an established neighbourhood of Hamburg, that enclose a large inner yard as the buildings, 1930 vintage, occupy a whole city block.

The inner courtyard, with the three new buildings in the centre

The courtyard is the size of a small city park.  It’s mostly lawn, some trees, with a few swings for kids and a sandbox.  People have strung a few communal clothelines.  There are a few flower beds, but surprisingly no vegetable garden.  Stephan explains that people are concerned that the soil may still be poisoned by the residues of bombing from the second world war.  The courtyard is not fully open; there are a few fences that divide the courtyard into maybe three sections. Too bad.

We went to another one of the courtyard sections, one that can be accessed from the street.  There is a break between the buildings, wide enough for a car.  There is a small parking lot.  This is a change; in the sixties, much of the courtyard was a charmless parking lot.  There is only a little stub of a parking lot left; the rest was progressively returned to grass, or built over.

The new apartment blocs in the courtyard

This is the development that caught my eye.  The former parking lot is now home to three mid-size apartment buildings, three-story structures completed in 2012 with 32 dwellings.  These have the sharp look of very energy efficient buildings.

Walking around, we struck a conversation with a woman named Elke, a mother of twins.  She invited us to her apartment.  It’s on the ground floor, very bright with natural light, despite it being an October afternoon; this is due in part to the open plan design, which is a relatively new concept here.  I found it very comfortable, and she confirmed that it is very well insulated, and has a heat exchanger to provide ventilation when it is very cold.  But windows can also be opened; this isn’t a box with stale air, far from it.  Again, I was impressed that, at least in German buildings, the more energy efficient ones are also the most comfortable ones, where the indoor air feels freshest.

She found the inner courtyard ideal for her boys (I forgot to ask; the twins look like they were five or six years old).  She says she doesn’t need to worry; the courtyard gives plenty of space to play, it is safe (no cars) and there are neighbours who also have kids to play with.  It was very easy to fit in.

This may unremarkable except for the fact that she is a single mom, and that this is a large, modern apartment in a desirable part of town.  But these three units were also built with the objective of providing affordable housing (part of the subsidy money comes from the city, part from the developer in exchange for different conditions), so the rent is means-tested.  In Hamburg, being a single mom does not condemn you to poverty.

Visiting the yard also solve another puzzle – are there no cats in Hamburg?  Or do they not go out?  There are many, and they do go out – but they stay safely inside the courtyards, well away from traffic.

And this far from the only addition to a city courtyard.  This type of infill has been done all over, increasing urban density in a manageable way, without altering the character of the urban fabric.  I already mentioned another complex nearby, Fette-Hӧfe, in a previous post.

A view of the courtyard from the kitchen window of the apartment of our friends

Call me naïve, but this strikes me as an ideal design for mid-level urban density: apartment blocks with large, airy courtyards that allow for some infill.  This strikes me as a form that Vancouver should use for development, something to provide housing for so-called missing middle.  There are a few examples in town; I can think of the Marquee building, or the co-housing development on 33rd.  There should be many more.

I do like courtyards, clearly.  More details about the neighbourhood of our friends can be found in previous posts, here and here, that I wrote when we first arrived in Hamburg.  I found that the city provides excellent documentation for its housing initiatives; much of what I visited I found in a publication (212 pages, free!) called Mehr Stadt in their Stadt: Chancen für mehr urbane Wohnqualitӓten in Hamburg (More city in the city: options for better quality urban housing in Hamburg, downloadable from the city site here).  As for the Richie quote, it’s from Richie, Alexandra 1998.  Faust’s metropolis: a history of Berlin.  New York: Carroll & Graf.

 

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Written by enviropaul

February 7, 2018 at 5:37 pm

The Green Network of Hamburg

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Hamburg’s green spaces

“Imagine leaving your house in suburbia and being able to walk, jog, or bike all the way downtown, following a system of interconnected wetlands and streams leading down to the major regional river.”

The Dancing Pants, public art along the Eilbeck

This sentence in an article by Celina Balderas Guzman (ref below) caught my eye.  She mentions that one would come across community gardens, sports fields, ecological reserves, as well as more technical features such as areas for sediment and runoff capture, or even energy generation. She mentions the role of wetlands in controlling pollution from urban runoff.

This sounds all fine, except for one thing: it is preceded by the heading “constructing our future”, as if this was a holy grail of urban planning, some kind of unattainable ideal of urban planning worth striving for.  In many cities, that may indeed be the case.

But there is at least city where what is described is not the future, but the reality.  That city is Hamburg, Germany.  Surely it is not the only one; but this is one city I know well, where I have walked and cycled extensively along its extensive network of trails and green spaces, so I will use it to illustrate the point.

Cycling along the Eilbeck canal (note the porous pavers)

At first glance, Hamburg doesn’t seem an obvious candidate for a green city.  It’s a prosperous merchant port city (the second largest in Europe), a manufacturing and publishing centre, busy labouring under the grey skies of the North Sea; not where you would expect a colony of tree-hugging nature lovers.  It’s also a modern city that had to rebuild itself repeatedly.  The British air force reduced the city to ashes and rubble in 1943, wiping out whatever remained of the historic city one hundred years earlier.  Before that, the occupying army of Napoleon had cut down every single tree in and around the city to ensure a clean line of fire for their guns.  That protecting nature may not have been a top priority would have been understandable.

But maybe that’s just it; after so much destruction, people get attached to what has survived, and to what can grow back.  And, true to form in a port city, Hamburgers are attached to the water.  It’s not just the shores of the Elbe river, where the port is located; every river and creek that run through the city, every canal, every lake and pond is sacred.  People have consistently refused any proposal to bury a creek, no matter how insignificant.  This is why there are so many bridges in Hamburg; but that is also why there are so many green corridors; these are the shorelines of all these creeks.

Schumacher’s connectivity plan, 1919

So when Hamburg planner Fritz Schumacher drafted his city plan in 1919, he already had his green axis delineated: the shorelines of the Elbe, Alster, Osterbek, Wandse, and Bille rivers and their tributaries.  This axial plan, with green radii converging on downtown, has broadly remained unchanged over the years.  What is new is the outer ring of (almost) contiguous green space that connect the linear corridors, like a wheel rim resting on spokes.  This outer ring is not all that different from others in cities such as Hanover or Leipzig, except that it is wholly within city limits.  The city is working on connecting the missing parts; for instance, Düppelstrasse, an ordinary street in the dense neighbourhood of Altona-Nord, will be turned into a green corridor to connect two of the neighbourhood’s parks.  The extent of this ring is remarkable: 90 kilometers long, it creates a rough circle 9 to 10 kms around the downtown area.  This supports the inner ring, which neatly defines the downtown area as it is set where the ancient fortifications were; a large part of the inner ring is the famous Planten un Blomen botanical park. Detailed maps of the rings can be found on the city website here, and details about the city’s initiative (in English) here, here and here.

The outer and inner rings of the Hamburg Green Net

What that means for the visitor is that you can indeed walk pretty much everywhere outside of downtown along a green trail or in a park, away from cars and noise.  I walked (and cycled) along the Alster and the Wandse from the centre to the city limits and further, on green paths along canals (near the lake), then through green linear corridors along a natural watercourse, with cafés and parks, wetlands, dams and weirs, including a large one on the Alster with a power station and fish ladder.  These areas are very popular for walkers of all sorts, and along the trails public art can be seen.

But I also walked along a small tributary of the Osterbek, the Seebek in the Steilshoop neighbourhood (hydrology nerds: it’s a little fourth order stream).  This is an ordinary residential neighbourhood of brown brick apartment buildings.  The creek wends its way between the buildings, alternating between wooded and grassy areas.  It’s a grey December day, there are few people around, and it’s a bit forlorn.  But I wanted to see the work that NABU, the local environmental organisation, had done to rehabilitate the stream.  Out went the concrete embankments; replacing them are natural meanders and large woody debris and rocks to increase the flow depth and make the stream effective as fish habitat.  NABU also created protected nesting habitats for kingfishers, bats, and solitary bees.  But this was done in a very German way (or so it strikes me): the environmental group works with the city and together they determine priority areas for conservation, and the city funds the initiatives and supervises the work alongside NABU volunteers.

The Seebek creek winds its way between apartment blocks

I also visited Eppendorfer Moor, a 26 hectare wetland by the Alster near the Jewish Hospital.  A friend had told me it was gorgeous; he probably visited in summer (in December, there was no sign of the endangered ferns said to grow there).  Still, I could see the control weir; this wetland, like many throughout the city, is not only a green space for ducks, it also provides storage capacity for rainstorms.   This urban pond has an interesting history.  Originally it was dug for peat, then drained for farming.  The 76th regiment had their shooting range there.  After the war, the plan was to fill the wetland with rubble.  But, in a move typical of Hamburg, locals thwarted the plan.  A night-time planting operation led by Werner Hoffmann, head of the Gardens Department, forced politicians to reconsider.  (Unfortunately this action brought in non-native species.)  What is remarkable is that this wetland, one of many in the city, is only about five kilometers from downtown.

But these are far from uncommon.  I counted twenty-six rivers, and gave up count of the innumerable lakes and ponds, public parks, nature reserves, community gardens, and connecting trails.  Even the numerous cemeteries are visited for their treed park-like appearance; indeed, the Ohlsdorf cemetery, at 391 hectares, is the biggest park-like cemetery in the world.

Eppendorfer Moor in winter

This is possible, in part, because Hamburg, despite being a large European city, is not particularly densely built; the average population density is similar to Toronto, and since much of the residential sector consists of four or five story walk-up apartment buildings, this leaves much room for green space.  There is also the fact that most of the industrial activity (the harbour, the Airbus works, the chemical and metallurgical plants) are all on the south side of the Elbe (where canals, not creeks, are the main water feature), leaving the core and the north free of heavy industry.   But the key is really in the creeks; by stubbornly clinging to their creeks, Hamburgers have ensured that green linear corridors were preserved.  This is good not only for the many who like to go spazieren, but also for the ecological integrity of the city.  Birds, insects, mammals, lizards, even plants thrive when they are not cut-off from each other by roads and buildings; and of course, the creeks themselves provide the aquatic habitat that supports the terrestrial food chain.

Imagine what Vancouver would look like if its many creeks such as Brewery Creek or China Creek had not been paved over; this may give you an insight into Hamburg’s topography.  Here we speak of daylighting creeks to restore the ecological habitats and undo the damage, whereas in Hamburg, aside from the pollution issues, there was little physical damage to most of the water habitat.  This also means that the city has much more storage and absorption capacity for large storms, and so lower vulnerability to rainstorm flooding.  This is a lesson that our own suburbs, such as Surrey, are now heeding.

Crossing the Alster on the Green Network

But if the green network in Hamburg already accomplishes much of what Balderas Guzman confines to the future (stores and clean excess runoff, provides natural habitats), there is something that it cannot do: provide a viable alternative for commuters.  Yes, some people do use the network, but it’s mostly for recreational use; the distances involved are too large for walking (or even cycling, in some cases), and – this is key – there is an excellent public transit system.  A blind spot in the much-criticized book Infinite Suburbia, where Balderas Guzman’s article appears, is the lack of an acknowledgment of the environmental problems caused by suburban development, in particular poor transportation.  This is an issue that a network of connected trails and wetlands, future or extant, cannot solve by itself.

Marvelous as it may be, as in the case of Hamburg.

 

 

 

Celina Balderas Guzman 2017.  Suburban Wetlandia.  In: Infinite Suburbia, edited by Alan Berger and Joel Kotkin, Princeton Architectural Press, New York, pg 489.

Written by enviropaul

February 1, 2018 at 9:56 am