River. Space. Design, 3rd edition

River. Space. Design.

Planning Strategies, Methods and Projects for Urban Rivers

River. Space. Design.

Planning Strategies, Methods and Projects for Urban Rivers

Third and Enlarged Edition

Martin Prominski

Antje Stokman

Susanne Zeller

Daniel Stimberg

Hinnerk Voermanek

Katarina Bajc

Nengshi Zheng

Birkhäuser · Basel

Foreword ∆ 5

Herbert Dreiseitl

Fundamentals

Introduction ∆ 8

Objectives ∆ 9

Selection of projects ∆ ∂∂

The book’s structure ∆ ∂2

Prerequisites for Planning

Urban River Spaces ∆ ∂4

Multifunctionality ∆ ∂5

Interdisciplinarity ∆ ∂6

Process orientation ∆ ∂7

Water Spaces and their Processes ∆ ∂8

Processes and their driving forces ∆ ∂9

Types of processes ∆ 20

Water landscapes as an expression of spatiotemporal processes ∆ 25

Designing Water Spaces ∆ 28

Water spaces and their limits ∆ 29

Types of limits ∆ 31

Riparian landscapes between control and dynamism ∆ 33

Design Catalogue

Introduction ∆ 38

Process spaces ∆ 39

List of process spaces and design strategies ∆ 42

List of design tools and design measures ∆ 44

Process Space A

Embankment Walls and Promenades ∆ 46

A1 Linear spatial expansion ∆ 52

A2 Selective spatial expansion ∆ 54

A3 Temporary resistance ∆ 56

A4 Placing over the water ∆ 58

A5 Tolerating ∆ 60

A6 Adapting ∆ 64

Process Space B

Dikes and Flood Walls ∆ 66

B1 Differentiating resistance ∆ 72

B2 Vertical resistance ∆ 76

B3 Reinforcing resistance ∆ 78

B4 Integrating resistance ∆ 80

B5 Temporary resistance ∆ 82

B6 Making river dynamics evident ∆ 84

Process Space C

Flood Areas ∆ 86

C1 Extending the space ∆ 92

C2 Placing over the water ∆ 96

C3 Tolerating ∆ ∂00

C4 Evading ∆ ∂04

C5 Adapting ∆ ∂06

Process Space D

Riverbeds and Currents ∆ ∂08

D1 Deflecting the current ∆ ∂∂4

D2 Grading the channel ∆ ∂∂8

D3 Varying the riverbed ∆ ∂20

D4 Varying the bank reinforcement ∆ ∂22

D5 Varying the riverbed reinforcement ∆ ∂26

Process Space E

Dynamic River Landscapes ∆ ∂28

E1 Allowing channel migration ∆ ∂34

E2 Initiating channel dynamics ∆ ∂36

E3 Creating new channels ∆ ∂38

E4 Restricting channel dynamics ∆ ∂40

Project Catalogue

Introduction ∆ 144

Process Space A

Embankment Walls and Promenades ∆ 148

Allegheny River, Pittsburgh, USA 150

East River, New York, USA ∆ 152

Elster and Pleiße Millraces, Leipzig, Germany ∆ 156

Fox River, Green Bay, USA ∆ 160

Leine, Hanover, Germany ∆ 162

Limmat, Zurich, Switzerland (Factory by the Water) ∆ 164

Limmat, Zurich, Switzerland (Wipkingerpark) ∆ 166

Rhône, Lyon, France ∆ 168

Seine, Choisy-le-Roi, France ∆ 172

Spree, Berlin, Germany ∆ 174

Wupper, Wuppertal, Germany ∆ 176

Process Space B

Dikes and Flood Walls ∆ 178

Elbe, Hamburg, Germany (Promenade Niederhafen) ∆ 180

IJssel, Doesburg, the Netherlands ∆ 182

IJssel, Kampen, the Netherlands ∆ 184

Josefsbach and Rems, Schwäbisch Gmünd, Germany ∆ 188

Main, Miltenberg, Germany ∆ 192

Main, Wörth am Main, Germany ∆ 194

Nahe, Bad Kreuznach, Germany ∆ 198

Regen, Regensburg, Germany ∆ 202

Sieg, Siegen, Germany ∆ 204

Waal, between Afferden and Dreumel, the Netherlands ∆ 206

Waal, Zaltbommel, the Netherlands ∆ 208

Process Space C

Flood Areas ∆ 210

Bergsche Maas, between Waalwijk and Geertruidenberg, the Netherlands ∆ 212

Besòs, Barcelona, Spain ∆ 214

Buffalo Bayou, Houston, USA ∆ 216

Ebro, Zaragoza, Spain ∆ 218

Elbe, Hamburg, Germany ∆ 222

Gallego, Zuera, Spain ∆ 224

Guadalupe River, San Jose, USA ∆ 228

Guitang River, Changsha, China ∆ 232

Ihme, Hanover, Germany ∆ 236

IJssel, Zwolle, the Netherlands ∆ 238

Kyll, Trier, Germany ∆ 240

Maas, Maasbommel, the Netherlands ∆ 242

Maozhou River, Shenzhen, China ∆ 244

Petite Gironde, Coulaines, France ∆ 246

Rhine, Brühl, Germany ∆ 250

Rhine, Mannheim, Germany ∆ 252

Seine, Le Pecq, France ∆ 254

Te Auaunga, Auckland, New Zealand ∆ 256

Waal, Gameren, the Netherlands ∆ 258

Waal, Nijmegen-Lent, the Netherlands ∆ 262

Wantij, Dordrecht, the Netherlands ∆ 264

Wupper, Müngsten, Germany ∆ 266

Yiwu and Wuyi Rivers, Jinhua, China ∆ 268

Yongning River, Taizhou, China ∆ 272

Process Space D

Riverbeds and Currents ∆ 274

Ahna, Kassel, Germany ∆ 276

Ahr, Bolzano, Italy ∆ 278

Alb, Karlsruhe, Germany ∆ 282

Birs, Basel, Switzerland ∆ 284

Kallang River, Bishan, Singapore ∆ 286

Leutschenbach, Zurich, Switzerland ∆ 290

Neckar, Ladenburg, Germany ∆ 292

Seille, Metz, France ∆ 296

Soestbach, Soest, Germany ∆ 298

Wiese, Basel, Switzerland ∆ 300

Wiese, Lörrach, Germany ∆ 302

Process Space E

Dynamic River Landscapes ∆ 304

Aire, Geneva, Switzerland ∆ 306

Isar, Munich, Germany ∆ 310

Losse, Kassel, Germany ∆ 314

Murg, Frauenfeld, Switzerland ∆ 316

Schunter , Braunschweig, Germany ∆ 318

Wahlebach, Kassel, Germany ∆ 320

Werse, Beckum, Germany ∆ 322

Appendix

Project Credits and References ∆ 325

Further Reference Projects ∆ 334

Glossary ∆ 338

Selected Bibliography ∆ 341

Indices ∆ 345

Authors ∆ 352

Acknowledgements ∆ 352

Illustration Credits ∆ 353

A6

All design tools in A6 can be combined with – – – – – – – –

A∂.∂ Intermediate levels

A∂.2 Terraces

A∂.3 Broad riverbank steps

A5.4 Submergible riverside paths

This design strategy employs elements that float on the water surface and visibly rise and fall with water level fluctuations, while the water can flow unimpeded beneath them. Through their prominent location on the open water surface, floating elements can act as a strong visual feature in the cityscape and are therefore very important in open space design. Traditionally, this principle has always been applied for shipping piers on major rivers, but the variety of uses has increased significantly in recent years; in addition to houseboats, bathing ships and floating islands have become a permanent feature of the cityscape in many European urban centres. Depending on the degree of integration with the open spaces on the adjoining riverbank, these elements are temporarily or permanently attached to a particular place. Their direct proximity to water and dependence on the watercourse flow rate variations accentuates people's perception of the river processes – from the strength of the current to the various water levels. Because the principle of floating elements starts at the water surface and adapts flexibly to water levels, the flow resistance and the discharge cross-section of the watercourse are hardly affected.

If the pontoons are to be accessible from the bank, the height difference between the fixed riverbank edge and the floating elements must be compensated for by a flexible construction. Floating elements are easier to use in slow-flowing watercourses; where the current is strong, along with robust moorings or other fixings, a protective shield against dangerous flotsam during high water levels is recommended.

A frequently used and simple variation on the ‘Adapting’ theme is the floating jetty, which can serve as a landing stage for boats or bathing pontoons and create highquality recreational open space right on the waterside. These flexible constructions can be architecturally interesting and raise awareness of the water’s dynamics. The jetty on the re-exposed Elster Millrace (Elstermühlgraben) in Leipzig permits access to the water and serves as a canoe landing place.

– – – – – – – –

East River, New York ∆ 152

Elster and Pleiße Millraces, Leipzig

∆ 156

Fox River, Green Bay ∆ 160

Elbe, Hamburg, Promenade Niederhafen

∆ 180

+ Limmat, Zurich, Women's Bath

Stadthausquai ∆ 335

Floating islands

Moored ships

Floating islands open up spaces that were previously inaccessible: on the edge of the old city fortifications in Hanover a floating island was built to be used as a bistro, making it possible to sit right beside the water. Such small islands are directly exposed to water level fluctuations, waves and the current, so that the water is experienced almost as if from a boat.

– – – – – – – –

Leine, Hanover ∆ 162

Elbe, Hamburg, HafenCity ∆ 222

+ Seine, Paris, Berges de la Seine ∆ 337

Decommissioned or specially constructed ships can serve as houseboats, studios, discotheques, cafés or restaurants. In Berlin and Vienna, ships containing swimming pools make it possible to feel as if one is swimming in the river. These can be moored at places where the river water quality is not good enough for bathing. These ships are not dependent on the river water level and offer a good way of enlivening inner-city water spaces.

– – – – – – – –

Rhône, Lyon ∆ 168

Spree, Berlin ∆ 174

Elbe, Hamburg, Promenade Niederhafen

∆ 180

+ Danube, Vienna, Bathing Ship ∆ 334

Elster Millrace, Leipzig

Leine, Hanover

Spree, Berlin

Parks within the flood plain

Extensive natural areas

Agriculture

A flood plain can be designed as a floodresistant park. Plantings and furniture have to be designed and built to tolerate several days of submersion – examples are swamp cypress and heavy stone benches. Such features lend the park a striking and distinctive character. A drainage system can also make the park’s green spaces usable again shortly after flooding – at Petite Gironde in Coulaines, for example, drainage pipes were laid under the entire lawn area to ensure this.

Besòs, Barcelona ∆ 214

Buffalo Bayou, Houston ∆ 216

Ebro, Zaragoza ∆ 218

Gallego, Zuera ∆ 224

Guitang River, Changsha ∆ 232

Petite Gironde, Coulaines ∆ 246

Seine, Le Pecq ∆ 254

Te Auaunga, Auckland ∆ 256

Wupper, Müngsten ∆ 266

Yiwu and Wuyi Rivers, Jinhua ∆ 268

Yongning River, Taizhou ∆ 272

Kallang River, Singapore ∆ 286

Seille, Metz ∆ 296

Wiese, Lörrach ∆ 302

River forelands are suitable sites to allow new natural flood plain environments to emerge from former agricultural areas. To permit natural succession until the now rare riverside woodland reappears is often not possible, as the dense woodland obstructs floodwater discharge. In the Netherlands, extensive grazing systems with ponies, highland cattle and wild horses were developed. As the animals cannot prevent all growth through grazing alone, however, alternative ideas are currently under discussion such as clear-cutting every 10–15 years. Between these interventions the vegetation can develop freely. In some places, carefully planned access systems guide visitors to relieve pressure on sensitive zones so that the area can also be used for recreation. In the Vreugderijkerwaard, by contrast, access is strictly limited, although the area can be crossed on a boardwalk leading to a birdwatching hide.

Ebro, Zaragoza ∆ 218

IJssel, Zwolle ∆ 238

Kyll, Trier ∆ 240

Waal, Gameren ∆ 258

Yiwu and Wuyi Rivers, Jinhua ∆ 268

Ahr, Bolzano ∆ 278

Aire, Geneva ∆ 306

+ Elbe, Lenzen, Large-scale Nature Conservation Project in the Elbe Valley ∆ 334

Depending on how frequently they are flooded, today many areas in river plains are used for extensive grazing or even arable purposes, as this view from the dike across the polder near Ingelheim on the River Rhine shows. Financial incentives encouraged farms to permit flooding of their lands again. On the Bergsche Maas in the Netherlands the farmers themselves initiated setting the dikes further back so that the Overdiepse Polder could once again serve as a flood space. The farm buildings were moved on top of mounds. In areas close to towns and cities, agricultural uses can enhance local recreational areas and release the municipality from the burden of maintenance costs.

Bergsche Maas, between Waalwijk and Geertruidenberg ∆ 212

Rhine, Brühl ∆ 250

+ Rhine, Ingelheim, ‘Polder Ingelheim‘ Floodwater Retention ∆ 336

Petite Gironde, Coulaines

IJssel, Zwolle, birdwatching hide

Rhine, Ingelheim, Polder Ingelheim

Camping and caravan sites

Events grounds

Stabilised wetland

Camping and caravan sites in riparian landscapes are very attractive because the location directly adjacent to the water is convenient for water sports and generally regarded as conducive to recreation. This campsite on the Reiß Island in Mannheim is particularly attractive because of the extensive gravel beach beside it. The pitches are mainly used in the summer months when the risk of flooding is low, but to exclude the hazard completely the possibility of flooding has to be communicated clearly to visitors so that the site can be evacuated quickly in the event of an unexpected flood. In Maasbommel on the Gouden Ham the campsite also rents out small bungalows on piles that can remain on site during flooding.

– – – – – – – –

Maas, Maasbommel ∆ 242

Rhine, Mannheim ∆ 252

River plains, retained as extensive open spaces in cities, can provide sites for open air concerts and other major events, such as the annual ‘Rheinkultur’ Music Festival near Bonn, which would be difficult to stage elsewhere because of the space required and the noise it causes. These events usually happen in the dry summer months and only a few fixed installations such as the stage foundations are needed; festival marquees, toilet facilities and food and drink stands can be set up and dismantled. In Ladenburg, a permanent events stage was installed as a flat, light construction on the bank of the River Neckar that presents no obstruction to high water discharge and is used for the annual festivals.

– – – – – – – –

Main, Miltenberg ∆ 192

Petite Gironde, Coulaines ∆ 246

Yiwu and Wuyi Rivers, Jinhua ∆ 268

Neckar, Ladenburg ∆ 292 + Fulda, Kassel, Flood Ditch Area ∆ 334 + Rhine, Bonn, ‘Rheinkultur‘ Music Festival

∆ 336

East River, New York

Reinforced and engineered wetlands are usually designed with the aim of restoring riparian zones which had previously been reinforced by bulkheads or otherwise. Typically, elements for shoreline stabilisation such as rock sills are placed at the edge of the marshland to prevent erosion. This type of reinforcement provides a zone of calm water, where wetland vegetation can take hold and form an intertidal habitat. Geotextiles often initially secure the vegetation. Such areas can only be used on flat to moderate slopes, in slow-flowing rivers near an estuary with tidal fluctuation and weak currents. The specific fluvial dynamics of the river also have to be taken into consideration in this approach as the installation of a hardened edge can hinder sediment from migrating downstream. In Yanweizhou Park the floodable wetland area was constructed on terraces which are gradually submerged and fill with silt after every flood. In Brooklyn Bridge Park and Yanweizhou Park the wetland is also used to filter and purify the stormwater runoff from the sealed surfaces before it enters the river.

East River, New York ∆ 152

Yiwu and Wuyi Rivers, Jinhua ∆ 268

Rhine, Mannheim, caravan site on Reiß Island

Neckar, Ladenburg, permanent stage

Design tools

A5.5 Submergible boardwalks and overhangs

C1.4 Reprofiling the flood plain

C2.3 Buildings on piles

C3.1 Paths within the flood plain

C3.4 Parks within the flood plain

C3.5 Extensive natural areas

C3.8 Events grounds

D4.2 Living revetment

Yiwu and Wuyi Rivers

Yanweizhou Park, 2014

Jinhua, China

River data for project area

Catchment area: < 6000 km²

Width of riverbed: Yiwu River 226 m; Wuyi River 173 m

Location: 29° 05’ 35” N – 119° 39’ 58” E

Jinhua City, Zhejiang Province, lies at the confluence of the Wuyi and Yiwu Rivers, where both meet to form the Jinhua River; here one finds the Yanweizhou wetland, covering 26 hectares. It is the last piece of natural riparian wetland to remain relatively intact in the urban fabric of Jinhua, although it has suffered from fragmentation, erosion and sand quarrying. A monsoon climate is characteristic of Jinhua, and the Yanweizhou riparian wetland is affected by annual monsoon flooding. The initial proposal made by Jinhua city officials to tackle these challenges was to protect the wetland against 20-year and 50-year floods by erecting high concrete retaining walls. These had already been applied to enhance flood protection and land reclamation elsewhere in the city; however, their cumulative effect worsened the destruction caused by the floods. Implementing the wall would also have had the effect of impeding water flow and the silt deposits that sustain and rejuvenate the lush wetland ecology. It would have further severed the connection between the riparian flood plains, the river and the city. Therefore, the designers opposed the idea and advocated demolishing the existing artificial floodwater infrastructure on that site.

The flooded landscape Instead they proposed a terraced river embankment planted with native flood-tolerant vegetation to accommodate annual flooding. This was achieved by the cut-and-fill technique and by adapting the site to the earlier topographical interventions and pioneer vegetation which had emerged as a result of quarrying for sand. The secondary growth of poplar trees (Populus canadensis) and Chinese wingnut (Pterocarya stenoptera) was predominant in the existing wetland, providing a habitat for native birds such as egrets. This biodiversity was increased by additionally planting other native vegetation supportive of local wildlife. The terraces are reachable via steps and equipped with urban furniture and pavilions, which are submergible and not accessible

Flood Areas

during floods. A riparian habitat with tall grasses on the terraces is rejuvenated by each such event, as the water irrigates the site and deposits fertile silts. Stormwater, which flows in the opposite direction from the park into the river, is filtered and purified when passing through wetland vegetation of the terraced river embankment. During flooding the inner lake also functions as a retention area which expands and eventually merges into the adjacent rivers. During the dry season the water from the rivers percolates through the gravel layers into the lake, undergoing filtering in the process. The lake thus provides cleaner and calmer water in a safer environment in comparison to the riverbanks. Therefore here, on the lake, one finds areas where people can come into direct contact with the water. The park is covered with a layer of permeable material and has a system of circular bio-swales to enhance stormwater infiltration.

1 The park extends across a flood plain at the confluence of the Wuyi and Yiwu Rivers. The area is well-connected to the city on both riverbanks via an extensive pedestrian network across the Bayong Qiao Bridge, which can be used even in times of flooding [C3.4]. The colourful bridge alludes to the Bench Dragon Dancing tradition and has become a landmark for the entire city.

2 The schematic cross-section shows the riparian bank and the terraced embankment, which is inundated during floods.

3 Another path system runs almost at water level to connect parts of the park across the water bodies [C3.1].

4 Visitors are given several opportunities to come into contact with water at the lake in the heart of the park. The lake itself serves as a retention waterbody and is submerged during monsoon floods, thus reconnecting with the river.

5 The paths are covered with gravel and thus are permeable. They lead to all parts of the park, including the terraced embankment, which is dense with native flood-tolerant vegetation.

Bayong Qiao Bridge Connectivity in the park is ensured by flood-adapted boardwalks, paths and ramps leading to the wetland area, which are submerged during 20-year flood events. An iconic new bridge meanders above the park for 700 m, linking it with the northern and southern districts of the town on both sides of the confluence, even when the park itself is submerged. It lies higher than the 200-year floodwater level, with ramps leading to various locations in the city. Powerful flood dynamics can be observed from above and remind people of the enormous strength of the bodies of water surrounding them. In the dry season it gives visitors the opportunity to observe the natural riparian habitat from above without disturbing it. The bridge has become an important landmark and a cultural asset for the city.

6 An aerial view of the park during the dry season

7 Vegetation was chosen due to its capacity for flood-resilience and planted to revitalise former sand quarries, which had degraded the landscape.

8 The native grasses display vivid colours throughout the year.

9 The iconic Bayong Qiao Bridge

10 An aerial view of the park during the monsoon season shows areas submerged during a 20year flood.

11 The concrete flood wall needed to be removed to build the terraced embankment. The cutand-fill earthmoving method meant that earth from the cut equalled the amount of fill.

12 Submergible boardwalks [A5.5]

13 A structure on piles overlooking the wetlands [C2.3]

Design tools

B6.1 High water marks

C1.1 Setting back the dike

C1.3 Flood channels

C1.4 Reprofiling the flood plain

C1.5 Backwaters

C3.1 Paths within the flood plain

C3.5 Extensive natural areas

D1.2 Dead wood

D1.3 Laid stone groynes

D5.3 Ramps and slides

E1.2 Semi-natural riparian management

E3.1 Creating meanders

E3.3 Creating multiple channels

Ahr

River Management of the Lower Ahr, 1999–2023 (ongoing)

Autonomous Province Bolzano, South Tyrol, Italy

River data for project area

Stream type: Small fine substrate-dominated siliceous highland rivers

Catchment area: 629 km2

Mean discharge: 50 m3/s

One-in-100-year flood discharge (HQ100): 458 m3/s

Width of riverbed: 30 m; width of flood plain: 150–1100 m

Location: 46° 48' 29.96" N – 11° 55' 39.50" E

The River Ahr starts at an altitude of about 2450 m above sea level. It flows through the Ahr valley and reaches the River Rienz at an altitude of about 810 m. Its 53 km river course with its 629 km2 river basin makes it the most important tributary of the Rienz in South Tyrol in northeastern Italy.

In comparison with 1858, the 1999 status survey shows a significant increase in agricultural, residential and commercial areas and a halving of the surface area of alluvial forests. In the 1970s, large quantities of gravel were dredged from the riverbed, resulting in its lowering, a change in the channel morphology and a displacement of the flood plain. On the one hand, the original river valley alluvial forest was decoupled from the river, causing anthropogenic changes to the ecological conditions of the natural riparian woodland, while the village of St. Georgen, which is located next to the river, is subjected to frequent flooding. At the same time, several tributary streams are no longer suitable for fish passage, and the increase in grazing and recreational activities such as rafting and horseriding has put pressure on some high-sensitivity nature reserves.

An integrated river management system The Ahr River management scheme was launched by the water protection department of the Autonomous Province Bolzano as a pilot project in 1999. It integrates flood protection with nature conservation, providing flood security for residents in adjacent areas and infrastructure, while maintaining and improving the ecological condition of the river and offering recreational functions. The project consists of 13 subprojects along the Ahr from Kematen to the Rienz River, and their implementation started in 2002.

Restoring, reconnecting and revitalising the river spaces Five of the 13 subprojects aim to widen the riverbed, to raise the riverbed – once sunken due to quarrying – by filling it up with gravel, to restore the continuity of the riverbed, to improve the dry water flow and to return part of the surrounding original flood plain to the river. The introduction of dead branches fastened to the riverbanks increases nesting space for birds and promotes alluvial forest restoration. New gravel islands provide safe nesting sites for land-nesting birds during the spring snowmelt. Downstream, the two river tributaries, the Mühlwalderbach and the Hirschbrunnerbach, have been ecologically revitalised by removing the concrete channel structures. Further, the structural diversity of their riverbanks was enhanced by stone groynes that offer spawning areas for amphibians; the new concrete weir across the Hirschbrunnerbach has improved flood protection without affecting the flow of water. The new fenced footpath in Mühlwalderbach gives visitors the opportunity to get close to the river, while ensuring that the natural areas are not overly disturbed. The dried-up Schmidt valley has once again been connected to the Ahr River and reactivated. Stocker Pond has been reopened, and two new groundwater ponds have been formed around it, one creating undisturbed habitats for endangered species and the other serving as a landscape pond for people to relax next to.

1 The meandering River Ahr in the Tauferer Ahr valley.

2 Schematic cross-section showing the river park as part of the river flood plains, offering higher flow capacity during flooding periods.

3 The ‘Ahrblick‘ viewing platform.

4 Bird’s-eye view of ‘Ahrblick‘ by the River Ahr.

5 Terraced riverbank for recreation and flood protection at St. Georgen river park.

EDynamic River Landscapes

Design tools

– – – – – – – –

C1.2 Branches

C1.4 Reprofiling the flood plain

C3.1 Paths within the flood plain

D1.2 Dead wood

D1.3 Laid stone groynes

E1.1 Removing riverbank and riverbed reinforcement

E2.1 Reprofiling the channel cross-section

E2.2 Introducing disruptive elements

E3.1 Creating meanders

E3.3 Creating multiple channels

Murg

Murg-Auen-Park, 2010–2015

Frauenfeld, Switzerland

River data for project area

Stream type: Colline, large, flat, calcareous

Catchment area: 617 km²

Mean discharge: 15.5 m³/s

Mean flood discharge: 260 m³/s

Width of riverbed: 15 m; width of flood plain: 50 m

Location: 47° 33' 47.35" N – 8° 53' 50.55"

From former army training area to the Murg Meadow Park The MurgAuen-Park is situated on the north side of the city Frauenfeld, next to the main railway station, with the River Murg running through to the north. Due to flooding the Murg was canalised in 1867, its former flood plain was cut off from the river and became an army training area. After the military grounds fell into disuse, they became a piece of wilderness in the city. Until 1990, this beloved woodland area, known as ‘Buebewäldli’ (boys’ grove), faced the prospect of being fragmented by a planned road project. With awareness of its high potential, it was saved from becoming a residential site and transformed into a multifunctional river park in the city. The Murg-Auen-Park today makes the river dynamics visible, it provides habitats for flora and fauna and allows children and adults alike to experience nature.

To reactivate the former flood plain of the Murg River, a 130 m long dike on the west side of the Murg was removed. A 450 m long meandering old river course within the ‘Buebewäldli’ has been reconstructed. The newly designed ‘old course’ of the Murg is less deep than the main river and flows calmly during normal weather conditions. With its small and shallow water surfaces and slow velocity, it offers extensive protective habitats for fauna and flora. During flood events, the water of the Murg overflows its banks formed of large rocks and floods the low-lying areas. The old river course as a flood bypass has lowered the flood water level and reduced flood risk.

Reconstructed old course as bypass

Natural flood plain as a playground As the potential users were engaged in the planning process, it was decided that the whole natural space itself is the playground and there was no need to build additional equipment. Adults and children should learn to adapt and cope with the dangers. The river area is such a varied space that visitors of all ages can have fun. Children play in the sand on the beach and observe little creatures in the water; older children collect and stack stones; dead branches fall on the river edges creating a place to rest; and large rocks on the beach provide a place for picnics and sunbathing. Curved bridges cross the river channels and give pedestrians access to the park. A spacious pavilion can be rented for birthdays and club celebrations.

Revitalised Murg River The flow of the river has been achieved by converting the existing sills into flat block ramps, allowing full accessibility for fish. Groynes along the river provide diverse flow conditions and habitats. The endangered fish species Nase (Chondrostoma nasus) has been re-established in the revitalised Murg. The Murg-AuenPark now provides more flood protection for the neighbourhood, offers more space for flora and fauna and has become a beloved place for all ages in the city of Frauenfeld.

1 Aerial view of Murg-Auen-Park.

2 Schematic section: The originally canalised old riverbed has been newly designed, with groynes and vegetation making the riverbanks stable and more biodiverse. In the middle of the section, the old original channel has been reactivated as a bypass during flood events.

3 The lowered western riverbank is becoming an attractive place for relaxation and water activities.

4 The new bridge leads over the flood plain and links the footpath with the neighbourhood.

5 Vegetation on both sides of the old Murg riverbed.

6 Observing, playing and learning in nature.

The first edition of this publication, released in 2012, was the result of the research project ‘Process-oriented design of urban river spaces’ undertaken from August 2008 until March 2011, which was financially supported by DFG (German Research Foundation). The project was conducted by Institute of Open Space Planning and Design, Faculty of Architecture and Landscape Sciences, Leibniz University Hanover.

The second and expanded edition, with contributions by Katarina Bajc, was published in 2017. This third and expanded edition, to which Nengshi Zheng contributed, was supported by HafenCity University Hamburg and Leibniz University Hanover.

Project supervision: Martin Prominski, Antje Stokman

Project team: Susanne Zeller, Daniel Stimberg, Hinnerk Voermanek; Katarina Bajc (second edition); Nengshi Zheng (third edition)

Research assistance: Christoph Wust

Diagrams, drawings, project assistance: Amalia Besada, Jana Fischer, Niklas Hoepner, Rosalie Zeile; Namariq N. Alrawi, Arantxa Piñate (second edition), Josefine Siebenand, Corinna Haberkorn (third edition)

Translation into English: Bärbel Cunningham, Mic Hale, David Skogley

Editor: Ria Stein

Copyediting: Jessica Read, Esther Wolfram; Catherine Atkinson (second and third edition)

Graphic design: Tom Unverzagt (first and second edition); Anja Haering (third edition)

Production: Anja Haering

Paper: Condat matt Perigord, 135g/m2

Printing: Cuno, Calbe

Library of Congress Control Number: 2022951014

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The first edition of this book is also available in a German language edition with the title Fluss.Raum. Entwerfen, print-ISBN 978-3-0346-0686-8; e-ISBN (PDF) 978-3-0346-1174-9.

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River. Space. Design is a systematically organised reference book for the design and planning of river spaces. Urban river landscapes need to unite a broad range of requirements – most notably flood control, ecological considerations and open space design – often within tight space constraints. Taking a processoriented approach, this book offers concrete guidelines for sustainable longterm interventions.

This book contains a comparative analysis of more than 60 successful projects alongside rivers and streams worldwide, and dissects them into their individual design elements. The result is a catalogue of effective design strategies and tools that provides readers with an attractive and inspiring overview of the broad and varied spectrum of design possibilities for river spaces.

Each project is illustrated with photographs taken especially for the book and each principle is illustrated with explanatory diagrams. The book’s interdisciplinary structure is of interest to landscape architects, architects, engineers, urban planners and hydrologists alike.

For this third and enlarged edition, eight best-practice case studies mostly from North America and Asia were added.

Adding bed load ∆ Agriculture ∆ Art objects and relicts ∆ Attachable protection elements

∆ Backwaters ∆ Bank reinforcement as needed ∆ Bioengineered groynes ∆ Boulders and stepping stones ∆ Branches ∆ Broad riverbank steps ∆ Building over the existing reinforcement ∆ Buildings on piles ∆ Bypass culverts ∆ Cableways ∆ Camping and caravan sites ∆ Closable access ∆ Creating meanders ∆ Creating multiple channels ∆ Creating scour holes ∆ Dead wood ∆ Dike parks ∆ Dike steps and promenades ∆ Dikes as path networks ∆ Electronic warning systems ∆ Escape routes

∆ Events grounds ∆ Extending the flow length ∆ Extensive natural areas ∆ Fish passes ∆ Floating and amphibious houses ∆ Floating islands ∆ Floating jetties ∆ Flood channels ∆ Flood-tolerant buildings ∆ Fold-out protection elements ∆ Foreshores ∆ Glass walls ∆ High water marks ∆ Incorporating a straightened channel ∆ Influencing perceptions of the wall height ∆ Integrating flood protection walls ∆ Intermediate levels ∆ Introducing disruptive elements ∆ Invisible stabilisation

∆ Laid stone groynes ∆ Large single rocks ∆ Living revetment ∆ Marinas ∆ Masonry riverbank revetment ∆ Moored ships ∆ Mound principle with buildings ∆ Mounds ∆ New embankment walls

∆ Overhangs ∆ Parks within the flood plain ∆ Partially naturalising the riverbank ∆ Paths within the flood plain ∆ Perceptible changes in fluvial patterns ∆ Piers and balconies ∆ Piled stone groynes

∆ Polder systems ∆ Portable protection elements ∆ Ramps and slides ∆ Regulating water extraction

∆ Removing riverbank and riverbed reinforcement ∆ Reprofiling the channel cross-section

∆ Reprofiling the dike section ∆ Reprofiling the flood plain ∆ Retaining sightlines ∆ Retention basins

∆ River access parallel to the bank ∆ River access perpendicular to the bank ∆ Riverbed sills ∆ Sand and gravel beaches in bays ∆ Sand and gravel beaches on inner bends ∆ Selective bank reinforcement

∆ Semi-natural riparian management ∆ Setting back the dike ∆ ‘Sleeping’ riverbank reinforcement

∆ Sports facilities and playgrounds ∆ Stabilised wetland ∆ Stone revetment ∆ Submerged groynes

∆ Submergible boardwalks ∆ Submergible furniture ∆ Submergible planting ∆ Submergible riverside paths ∆ Superdikes ∆ Surmounting the embankment wall ∆ Suspended pathways ∆ Terraced gabion revetments ∆ Terraced stone revetment ∆ Terraces ∆ Trees on dikes ∆ Underwater steps ∆ Using the historical city wall ∆ Varying the riverbed and transverse structures ∆ Warning signs and barriers ∆ Watertight facades ∆ Widening the channel