艾尔河河畔花园设计

Group Superpositions事务所

Group Superpositions

艾尔河河畔花园设计

Designing a Garden along the River Aire

Group Superpositions事务所

Group Superpositions

1 俯瞰河流与运河General view of the river and the canal

2 概念设计方案：现存的运河和新的河流Conceptual scheme : the existing canal and the new river

3 河流形态演变的研究Study of the evolution of the river morphology

位于日内瓦南部的艾尔河，翻山越岭，流经历史悠久的农耕村落。河流从19世纪末到20世纪40年代逐步改造为运河用以防洪。2001年，日内瓦市政府发起了一场高水准的竞赛，旨在将河流恢复到更自然的形态。事实上，更深层次的想法是希望通过拆除运河，使河流恢复之前蜿蜒曲折的形态，重塑河流原始风貌。这是个没有公开声明的要求，支撑它的主要理由是公众对运河非自然直线形的抵触。这就是一种回归，恢复纯粹的自然状态；这就是背后的设计故事，寻找失落的天堂。

初始方案被否决之后，设计团队提出了新的设想，改造现有运河，为自然河流创造广阔而自由的流动空间。两者相互平行，彼此呼应。在这个过程中，运河的角色就像是显示转变的指示器，亦或是参考线，让游客能够理解和感受河流在改造前后的变化。该方案成为了叠加两种状态的动态过程。

设计团队赢得了竞赛并且主张任何替换或无视场地现有状况的设计将无法真正地达到原始的、自然的状态。

在20世纪80年代，在安德烈·科博斯和博纳多·萨齐尼的影响启发下，日内瓦大学建筑学院认真地对这种自然设计观进行了试验。一开始人们尝试在建筑设计中使用绘图修复方法。然后，将此延伸并应用于整个设计领域，逐渐演变为一种由伊莉萨·罗森堡命名的地质学猜想。在这个猜想中，人们仔细地思考并调控着场地的现状条件和可能的改造方式。这个方法成为了实践的基础，在此之上人们选择理性的改进方法或深化途经。在详细的影响因素研究中，历史文献、过往规划、历史图像以及现存的现场调研资料和测量数据都被纳入考量。

首先对郎西花园及周边艾尔河流域的过街天桥和隧道进行实践，设计方案包含了对运河现状和河流预期改变的思考。换句话说，此实践并不是为了马上解决问题，而是通过场地条件的模拟叠加去了解河流位移情况。在郎西花园，复杂的隧道或桥梁就像一个连贯的门槛，隧道透过堤坝，桥梁跨过河流，它是项目实施前的场景预演。

4 总体规划General plan

5 水景细部River detail

艾尔河改造项目旨在试图扭转竞赛的潜在初衷：仅仅只是否定——否定土地、历史以及多年来河床沉积与河流形成之过程。而设计团队抵制对文化、建筑文脉与场地形态之间联系的破坏。

竞赛官方要求更偏向生态方面，仅仅重视环境改善的合理需求，而忽视了任何设计价值与考量。自然与文化被置于完全相反的两个极端。

设计团队则提出另一种方法，从而将紧迫的生态迁移与更宏观的文化变更结合在一起。设计通过复杂的组织将新的河流空间和之前运河中的一系列花园联系在一起。整个设计成为了一个线性的花园。

约翰·迪克逊·亨特认为，花园是自然的3种层次中的重要一环。花园既蕴含探索的欲望，又拥有享受的欢愉。在整个流域原有的山丘形态和人为改造的痕迹中，这条狭长的河畔花园组织着这些场面、视野、冲突、材料等元素，旨在为脆弱而珍贵的土地导入问题、思考和希望。花园设计需要冷静与自生，最终生成一系列层级与功能分化的场所，以及能够承载人们各种活动的路径。运河的场地印记是建立这种自生性的关键。一个永久的印记——它限制并塑造着一组连续的场景并引入复杂的时间性，包括过去和未来，回忆和欲望。(1998年，我们试图去探寻阿姆斯特丹的伯默纪念公园的场地印记与人类活动间的关系。一架飞机在住宅区坠毁后，我们把损毁建筑物留下的痕迹视为新的开端和希望，一些已经消失了的东西仍然留存于亲历者的心里)。

6 运河边的水生花园Water gardens in the canal

7 河流的流动轨迹模式The launching pattern of the river

8 运河边的花园Gardens in the canal

对场地印记和活动回忆的融合运用需要精妙而审慎的设计手法。它不应该被理解为回到过去，而应该成为亲历者所描绘的未来。

鉴于此，一些具有情感冲击力的场景已经成功融合于场地设计中。通过加入新的情感或情绪来加深对场地的新的认知，可以持续地吸引游客。启动人们的非自主记忆过程，能够削弱时间和空间的感受。这样的刺激转移了期望，也唤醒了深埋的、被遗忘的感觉。悬挑于水面之上的混凝土平台，吸引游客靠近来倾听、细嗅和触摸这溪流。当一个小男孩跪到河流边触碰水流并大声高呼的时候，他所有的感官和快乐就被唤醒了。

在长达5km的河畔花园中，设计了大量的人工干预设备，保证了河流的可控性，并为附近的日内瓦市中心抵御洪水提供了安全保障。

多学科负责团队至关重要，这很大程度上保证了安全性的构建，以及对生物和生态改善的全方位提升，包括精确的土壤质量控制，努力避免任何基底产生大的变动。该团队在挖掘修建新河床的材料与不同类型堤坝的材料再利用的研究设计中，取得了近乎完美的平衡。

对于河床本身的设计和施工，两个连续的建设阶段使用了两种不同的方式。显然“河流设计”是一个有趣的术语，河流自己就会流淌出自由而完美的设计。设计团队意识到建立一个固定的河床这种常用的设计方法是无用的，也就是通常工程师们通过科学计算或者景观设计师通过田园模拟而采取的方法。在第一阶段，我们尝试去除土地的腐殖质层，让河流自由地流动形成路径。最终这将成为一个完美的河流设计。

但是，河流设计成功与否主要在洪水季节接受检验，因此到这个过程产生效果自然需要时间。由于项目建设迫在眉睫，国家环境部门敦促设计团队找到一种方法，更快地获得更多元化的新河床。

在第二阶段，为了找寻答案，我们将渗流现象考虑其中(一种透过多孔材料的液体)，我们提供了图纸和模型，并最终设计了一个钻石形状的模式，这种模式开启了一系列复杂的、不固定的流动渠道。

我们沿着整个新的河流空间挖掘了这些渠道，保持对河流竖向的精确控制。这些菱形岛屿易被分解，它们的规模被塑造成能承载之前蜿蜒河流流量的大小。

最终结果是壮观的，设计启发了大地艺术家的创作，并且明显地使人为干预的效果转化为一个自然的情况，然后留给大自然慢慢地去侵蚀雕琢。在项目中有一些相似的工作和交集：我们创建了一个蓝图，一种发展模式，该形式可称作河流和地形之间的游戏。

9 运河边的花园Gardens in the canal

10 水景细部River detail

新河道空间启用6个月后，结果远远超出预期：河流流淌使得多样化的材料、砾石和砂自然散置。随着时间的推移，菱形的几何形矩阵被显著地优化了。

我们必须接受这一悖论：人为规划越明确的河流发展网格，河流越能自由地做出设计。

(编辑/张希)

11 内部河堤Dikes interior

项目区位：瑞士，日内瓦

客户名称：日内瓦市政府

完成日期：2016年

服务范围：景观设计

团队：Group Superpositions

图片提供：图1、7、13©Fabio Chironi；图2～6、10、11、14、16©Group Superpositions；图8、9、12、15©Jacques Berthet

翻译：宋怡

校对：唐彧玮

The River Aire flows South of Geneva through valleys historically devoted to farming. From late 19thcentury to the 1940s the river was progressively canalized to control flooding. In 2001, the State of Geneva opened a restricted competition to return the river to a more natural form. In fact, the general implicit idea of the competition program was really to restore the river to its original shape and settings, by destroying the canal and redirecting the flows into the former meanders. The main justification for this undeclared demand was the aversion for the unnatural straight line of the canal. It represented a kind of return, based on the well anchored conviction that it is necessary and possible to go back to a state of pure Nature. A search for a lost paradise was, in fact, the narrative behind all this.

Refusing this suggested solution, we instead proposed a plan which combined the existing canal, transformed, with a vast, new, parallel divagation space for the river. In the process the canal becomes the pointer (indication) for the transformations, a reference line giving the visitor a possibility to understand, to feel the before and after. A becoming which superimposes both situations.

We won the competition with the assertion that any project shifts the given situations, and is not a return to the former so called historical,original state of the things.

In the 1980s this design attitude was seriously experimented at the School of Architecture at the University of Geneva, under the illuminating influences of André Corboz and Bernardo Secchi. At the beginning possible applications of painting restoration methods were tested on architectural designs. Then, enlarged and applied to the whole territory, it progressively gave birth to what Elissa Rosenberg named a topographical imagination, where the description of situations and the proposed transformations were carefully thought out and controlled. This approach became the basis on which selected points of radical modifications or intensifications were chosen. In this patient examination of the context of the interventions, historical documents, plans and images were taken into consideration as well as the existing on site observations and measurements.

12 运河边的花园Gardens in the canal

Tested first at the Lancy garden, with the footbridge/tunnel (in the watershed of the Aire river), the design proposals evoke and contain both the given situation and the proposed shift. In other words, the solution doesn't erase the problem, but the superimposition of the given and the transformed makes the displacements more apparent. In Lancy, the complex tunnel/ bridge device functions like a long threshold, penetrating the embankment (tunnel), and crossing the stream (bridge), an evocation of the existing situation before the project was implemented.

Similarly, the aim of the Aire river project is to try to reverse what was implicitly planned in the competition: merely negations–negation of the territory, of its history, of the gradual sedimentation of its formation and transformation through the ages. The design opposes the destruction of all connections between the cultural and architectural traces and the overall morphology of their context.

13 河流全景General view of the river

The official justification for this programmaticinclination was, of course, an ecological one, in which the legitimated necessities of environmental ameliorations submerge all other considerations. A very common new disease nowadays, which implies an opposition between nature and culture.

Our project attempts to propose an alternative path, where the urgent ecological shifts are incorporated into a larger cultural change. The complex organization of the design associates the new river space and a linear series of gardens in the former canal. In reality the whole design becomes one linear garden.

14 运河边的水生花园Water gardens in the canal

Garden understood as one part of the trilogy of the three natures, as recalled by John Dixunt Hunt. Garden as place of questioning as much as pleasure. Facing the whole watershed, the original morphology of the mountains and the traces of the human modifications, this long rivergarden organises the situations, views, confrontations, presences, and materials, aiming at introducing into this fragile and precious territory questions, worries, hopes. The necessary calm and interiority, without which there is no real garden, yields organized sequences of differenciated places and paths allowing a reasonable distribution of people and movments.

The footprint of the canal is a key device for building this interiority. A permanent trace, which limits and frames a succession of situations, introducing a complex temporality, both past and future, memory and desire. (In 1998, we tried to reveal the traces of the site and its events in the design of the Bijlmer memorial, in Amsterdam. After the crash of an airplane into a housing complex, we kept the footprint of the destroyed building -this trace as both an evocation and a new hope, something which has disappeared and yet still remains). This use of traces, this memory of the places, is a very delicate task to manipulate or use. It must not be understood as a return to the past, but instead the becomings suggested by these encounters.

For that reason a certain number of brutal, shocking situations have been introduced at certain choosen places. To continually renew the attention of the visitors, to impose a new understanding of these places, through a new feeling, an emotional impact.To launch an unvoluntary memory process, the one able to shortcircuit time and space. Such provocations divert expectations, and also wake up deeply covered, forgotten sensations. A concrete slab cantileverd above the water asks you to "come near and hear, smell and touch the flow." An attempt to awake all senses and what a joy, when a young boy kneels and touches the flow and says " river! "

All along the five kilometers of the project, one encounters a great number of constructed interventions and devices that guarantee the control of the river and provide security against the floods for the nearby city center of Geneva.

The necessary multidisciplinary composition of the team in charge has successfullly achieved this goal of security, as well as the full range of the biological and ecological improvements, including a precise and decisive control of the soil quality and an effort to avoid any major displacement of the substrates.

A nearly perfect equilibrium has been achieved between the material excavated for the new riverbed and their reuse for the constructionof the different dams.

As for the design and construction of the riverbed itself, two successive phases of realization have produced two different manners. Obviously "to design a river" is an intriging term, as a river usually loves to design itself freely and perfectly.

Conscious of the useless efforts to design and build a fixed riverbed – an approach often taken by engineers (through scientific calculation) or landscape architects (through pastoral mimetic reflex), we try, in a first phase, to excavate the layer of humus and let the riverflow do its job. And the result was a perfect river design.

15 内部河堤Dikes interior

But, of course the river designs mainly during floods and consequently the process can take, certainly will take time. Impatient, the state environmental department urged us to find a way to get more quickly a more diversified new bed.

Fishing for an answer, we took into consideration the phenomenon of percolation (a liquid passing through a porous material) and wemade drawings and models and finally designed a diamond-shape pattern which opened a complex serie of undetermined channels for the flows.

These channels were excavated along the entire new river space, maintaining a precise control of the longitudinal profiles of the river. The dimensions of these lozenges islands were configured to be able to 'accept' the sizes of the former meanders.

The result is spectacular and suggests the devices of land artists, effecting clearly artificial interventions into a natural situation, thereafter left to the mercy of natural forces of erosion. There is in our project a familiarity with these works and an intersection: we just created a diagram, a launching pattern, whose forms address the play between the river flow and the prepared terrain.

Six months after the opening of the new river space, the results are beyond our most optimistic expectations: the river flows, while displacing diverse materials, gravels, sand and over time the geometrical matrix of lozenges is significantly modified.

We must accept this paradox: the more defined the launching grid given, the river, the more the river will be free to design.

Location：Geneva，Switzerland

Client：State of Geneva

Completion time：2016

Services：Landscape Architecture

Team of designers :Group Superpositions

Photo Credits：Fig.1/7/13©Fabio Chironi; Fig.2-6/10/11/14/16©Group Superpositions; Fig.8/9/12/15©Jacques Berthet

Translator：SONG Yi

Proofreader：TANG Yu-wei

16 运河边的水生花园Water gardens in the canal