Project in practice - Rubroek, Rotterdam

Project in practice R

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Index

Combined sewer system

Introduction

Separate sewer system

Aim and Focus

Tool kit for water

Relevance

Water assignment

Strategy

Separating runoff and sewer

Ground height map

Community spaces

Ground water level map

Flow of water from private to public

Subsurface potential map

Conclusions and reflection

Subsurface – Rubroek

References

Sub-soil information

2

Introduction

Rubroek

The climate change is an issue which will be one of the very important factors in future development of cities. Rotterdam municipality has focused its vision on making city a robust, attractive and economically viable keeping in mind this very factor of climate change by introducing Rotterdam Adaptive Strategy (RAS). Through integrated approach of not only experts but also the stakeholders originated the opportunities to the principles of RAS. These principles to be applied at small scale and at the city scale forma step further to climate proof Rotterdam.

Rubroek is situated on the edge of downtown Rotterdam. Despite a central location to city center the district has no image as such. There are around 8000 plus inhabitants in the neighborhood. The south side of the district was destroyed due to fire in 1940s. The demographic information of Rubroek gives the image of an older and affluent neighborhood with high number of social housing and presence of elderly care complexes. The combination of the large quantity of rental housing, inward orientation of the houses and the big amount of public courtyards in the building blocks, provide for a fuzzy image of the district. This is certainly not always good in image quality.

The urban vision for Rotterdam has several evidences for the need to redevelopment of unclear structure of districts, together with undefined open space. These offer possibilities for implementation of water storage in the form of surface water. The development of water storage capacity together with other spatial developments gives a boost to the neighborhood. By integrated approach the district creates opportunities for multiple problems to be solved at the same time. Problems not only like flooding but also sustainable, healthy and livable district. These points are the reason for this research to be conducted in Rubroek; one of the pilot sites in Rotterdam.

Report - Study on the development of a Climate-proof Rubroek - 2014 - Peter Arnts, Technical Trainee Municipality of Rotterdam Water Department | urban Rotterdam

3

Aim and Focus

Relevance

This project is a part of course Aquaterra which focuses on how to make smart urban plans using the parameters of the natural system – linking in an efficient way the hydrological cycle, the soil and subsurface conditions, technology and urban development opportunities.

Taking in account the subsoil in the urban design process gives the potential to create urban quality on the surface level. By understanding the geographic facts and the natural systems of a certain location, they can be used in the urban climate challenge. Besides that, the subsoil can contribute in reducing our energy consumption. Moreover, using the subsoil can have economic benefits.

Maintenance costs can be minimized, by allocating sensitive developments to good ground conditions.

Due to the changing climate and new visions integration of different disciplines is necessary for a sustainable development. But there is still lack of dialogue between different expertise. For instance, making urban design plans to which the subsoil infrastructure has to be changed and connected, information from the subsoil can be used in the beginning of the process of designing and therefore come to a more sustainable building process and end result.

The aim of the project is to analyze the subsurface conditions in Rubroek to identify the potentials and limitations to achieve the climate proof approach for the district. Further, using water assignment to understand the amount of water to be dealt within the neighborhood and different tools and solutions to be identified to accommodate this volume of water.

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Strategy for Rubroek The Rotterdam Adaptive Strategy aims at a robust, economically attractive and livable neighborhood.

Rubroek has a low livability and is draining out the inhabitants due to this reason. Along with making Rubroek climate resilient, the living environment also needs to be addressed. The intention is to keep the water that district receives through rain within itself instead of letting it flow in canal or flood. A very important factor for this approach is also to let the residents take up the initiative by making use of their private gardens or backyards.

Rubroek has low percentage of private green areas and it is majorly public with an absence of demarcation. This results in numerous undefined spaces or greens which are not used to its potential.

The ordinary world beneath our feet : ‘Underground’ by David Macaulay image source - http://socks-studio.com/img/blog/david-macaulay-underground-01.jpg

The first step in this project is to analyze the subsurface conditions and prepare a potential map with all the relevant information.

Second step will be from this map identify spaces which can be used to store or infiltrate the water to keep it within the district.

Third step will be to identify and make an inventory of different measures which can be made to store or infiltrate water based on its location.

Fourth step will be to use the water assignment to calculate amount of water to be received in a particular rainfall event. Based on this event develop a scenario to accommodate the relative volume of water.

Later it will be very important to identify these measures in terms of private initiatives and public ones, to understand and make the process more residents involved process.

5

Ground height Map

Legend <= -2.5 mt.

-2.5 mt. to -1.7 mt.

-1.7 mt. to -1.3 mt.

-1.3 mt. to -1.0 mt.

-1.0 mt. to -0.5 mt.

-0.5 mt. to 0.35 mt.

0.35 mt. to 3.0 mt. <3.0 mt.

10

6

0 source - http://www.gis.rotterdam.nl/gisweb2/default.aspx

70 30

Ground water level Map

-3.20 mt.

-2.70 mt.

-2.60 mt.

-2.10 mt.

-2.50 mt.

-2.40 mt.

-1.80 mt.

-2.30 mt.

-2.50 mt.

-1.65 mt.

-1.50 mt.

10 0

source - http://www.gis.rotterdam.nl/gisweb2/default.aspx

70 30

7

Subsurface Potential Map

Legend A

Civil layer Cables and pipes Buildings (flat roofs) Buildings (gable roofs) Valves (water management) Pump station (water management) Surface layer Green area (public) Green area (private) Water (canals) Paved surface B

Asphalt surface SubSurface layer

B

Archaeological relevance Polluted soil Underground oil tanks Explosives Low lying area A 10

8

0 source - http://www.gis.rotterdam.nl/gisweb2/default.aspx

70 30

Subsurface â&#x20AC;&#x201C; Rubroek

paved surface private

private

unpaved surface

The sections cut across the district indicate contamination of soil at different levels. From 0 to 1 meter layer of soil below ground, the contamination level is relatively low. However, from 1 to 2 meter of soil below ground level the contamination level of soil is high. The section also indicates the ground water level within the district is very much dependent on the drainage pipes. Moreover, the district has a combined sewer system, where the black, grey and rain water is transported through same pipe network to water treatment plant.

drainage pipe

part section CC

0-1 meter low contaminated soil 1-2 meter very high contaminated soil groundwater level

section AA

private

private

section BB

source - http://www.gis.rotterdam.nl/gisweb2/default.aspx

private

private

part section CC

private

private

private

private

private

private

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Sub-soil information

The adjacent 3d model explains the sub soil condition within the district. The first layer is a 5 meter deep called as anthropocene; as know as the urban layer. This layer is a mixture of peat, clay and sand.

Below the urban layer is 10 meter deep clay layer with some presence of peat. Later it is a sand layer.

The ground water travels usually in this urban layer towards the direction of canal.

Anthropocene / urban layer Clay layer Peat layer Clay layer

Sand layer

10

source - Jeroen Vuijk, Projectvoorbereider, Gemeente Rotterdam, Stadsontwikkeling, Millieu, Ruimte & Ondergrond, GIS & Datamanagement

Combined sewer system

source - Fransje Hooimeijer, artificial vs natural

11

Separate sewer system

12

source - Fransje Hooimeijer, artificial vs natural

Tool kit to keep water within the district

source - Performative nature- urban landscape infrastructure design in water sensitive city, PhD work, Taneha Bacchin

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Water assignment

14

source - Fransje Hooimeijer, artificial vs natural

Water assignment Based on the formula developed in the water assignment a scenario was considered for the neighborhood of Rubroek; with a rainfall event of 60 mm for 2 hours. Considering these values all the surface areas were calculated from flat roofs, gabled roofs, asphalt roads, paved roads, public greens, private greens to surface water. From the water assignment, rainfall event of 60 mm for 2 hours and all these surface areas amount of surplus water within the district was calculated. The neighborhood of Rubroek has a combined system; hence this volume of water is one which is discharged into the sewer system. If a separate is proposed in the neighborhood then this volume of surplus water needs to be accommodated for a rainfall event of 60 mm in 2 hours.

Further, after these calculations, a number of measures were considered which can be taken to accommodate water and check how much does a particular measure contribute in accommodating this volume. Every measure has its own effects and benefits to store the surplus volume. As a last measure, a scenario was considered if all these measures are taken together to see the result.

15

WATER ASSIGNMENT - RUBROEK, ROTTERDAM AREA (sq.mts.)

TOTAL AREA ASPHALT ROAD PAVED AREA PAVED PARKING GABLE ROOFS FLAT ROOFS GREEN (PUBLIC) GREEN (PRIVATE) PLAY GROUND SURFACE WATER PERMIABLE PAVED AREA INFILTRATION GARDEN WADI GREEN ROOF (EXTENSIVE) GREEN ROOF (INTENSIVE) SURPLUS WATER ON SITE

16

507280 48053 203734 19776 30771 96324 68529 16284 4618 19191

% area 100.00 9.47 40.16 3.90 6.07 18.99 13.51 3.21 0.91 3.78 0.00 0.00 0.00 0.00 0.00

rainfall (in mts.)

0.06

rainfall (duration in hours)

rainfall received (in surplus water (in correction (convert to 0 cu.mts.) cu.mts.) if negative) 2

30436.8 2883.18 12224.04 1186.56 1846.26 5779.44 4111.74 977.04 277.08 1151.46 0 0 0 0 0

2835.13 7538.16 731.71 1815.49 5297.82 -3769.10 -895.62 207.81 1151.46 0.00 0.00 0.00 0.00 0.00

2835.13 7538.16 731.71 1815.49 5297.82 0.00 0.00 207.81 1151.46 0.00 0.00 0.00 0.00 0.00 18426.12

Measure one Converting 40% of flat roofs into green roofs

Gable roof Flat roof

18426.12 cu.mts of surplus water

17

WATER ASSIGNMENT - RUBROEK, ROTTERDAM (measure 1 - flat roofs to green roofs) AREA (sq.mts.)

TOTAL AREA ASPHALT ROAD PAVED AREA PAVED PARKING GABLE ROOFS FLAT ROOFS GREEN (PUBLIC) GREEN (PRIVATE) PLAY GROUND SURFACE WATER PERMIABLE PAVED AREA INFILTRATION GARDEN WADI GREEN ROOF (EXTENSIVE) GREEN ROOF (INTENSIVE) SURPLUS WATER ON SITE

507280 48053 203734 19776 30771 57795 68529 16284 4618 19191

38529.6

% area 100.00 9.47 40.16 3.90 6.07 11.39 13.51 3.21 0.91 3.78 0.00 0.00 0.00 0.00 7.60

rainfall (in mts.)

rainfall (duration in hours)

0.06

40 % of flat roofs - 38529 sq.mts.

40% of flat roofs converted to intensive green roofs water absorbed/stored - 770.56 cu.mts CONCLUSION converting 40% flat roofs to green roofs absorbs/stores 4.18% of total surplus water

18

rainfall received (in surplus water (in correction (convert to 0 cu.mts.) cu.mts.) if negative) 2

30436.8 2883.18 12224.04 1186.56 1846.26 3467.7 4111.74 977.04 277.08 1151.46 0 0 0 0 2311.776

2835.13 7538.16 731.71 1815.49 3178.73 -3769.10 -895.62 207.81 1151.46 0.00 0.00 0.00 0.00 1348.54

2835.13 7538.16 731.71 1815.49 3178.73 0.00 0.00 207.81 1151.46 0.00 0.00 0.00 0.00 1348.54 17655.56

Measure one Converting 40% of flat roofs into green roofs

Gable roof

Green roof

Flat roof 4.1% 18426.12 cu.mts of surplus water

770.56 cu.mts of water stored/absorbed

19

Measure two Converting 10% of paved parking into green Converting 50% of balanced paved parking into semi permiable paving

Parking spots

20

18426.12 cu.mts of surplus water

WATER ASSIGNMENT - RUBROEK, ROTTERDAM (measure 2 - 10% parking green 50% balance parking semi permiable) AREA (sq.mts.)

TOTAL AREA ASPHALT ROAD PAVED AREA PAVED PARKING GABLE ROOFS FLAT ROOFS GREEN (PUBLIC) GREEN (PRIVATE) PLAY GROUND SURFACE WATER PERMIABLE PAVED AREA INFILTRATION GARDEN WADI GREEN ROOF (EXTENSIVE) GREEN ROOF (INTENSIVE) SURPLUS WATER ON SITE

507280 48053 203734 8899.2 30771 96324 70506.6 16284 4618 19191 8899.2

% area

rainfall (in mts.)

100.00 0.06 9.47 40.16 1.75 6.07 18.99 13.90 3.21 0.91 3.78 1.75 0.00 0.00 0.00 0.00

rainfall (duration in hours)

rainfall received (in surplus water (in correction (convert to 0 cu.mts.) cu.mts.) if negative) 2 30436.8 2883.18 2835.13 2835.13 12224.04 7538.16 7538.16 533.952 329.27 329.27 1846.26 1815.49 1815.49 5779.44 5297.82 5297.82 4230.396 -3877.86 0.00 977.04 -895.62 0.00 277.08 207.81 207.81 1151.46 1151.46 1151.46 533.952 -204.68 -204.68 0 0.00 0.00 0 0.00 0.00 0 0.00 0.00 0 0.00 0.00 17818.99

10% of paved parking converted to green - 1977.6 sq.mts. balance paved parking - 17798.4 sq.mts.

50% of balance paved parking converted to semi permiabe paving - 8899.2 sq.mts. water absorbed/stored - 607.13 cu.mts.

CONCLUSION converting 10% of paved parking into green and 50% of balance paved parking into semi permiable absorbs/stores 3.29% of total water

21

Measure two Converting 10% of paved parking into green Converting 50% of balanced paved parking into semi permiable paving

Paved Parking spots

Semi permiable Parking spots

Parking spots converted to Green 3.2%

22

18426.12 cu.mts of surplus water

607.13 cu.mts of water stored/absorbed

Measure three Converting 10% of asphalt into semi permiable paving Converting 10% of asphalt into paved surface area

Asphalt road

18426.12 cu.mts of surplus water

23

WATER ASSIGNMENT - RUBROEK, ROTTERDAM (measure 3 - 10% asphalt semi permiable 10% asphalt paved) AREA (sq.mts.)

TOTAL AREA ASPHALT ROAD PAVED AREA PAVED PARKING GABLE ROOFS FLAT ROOFS GREEN (PUBLIC) GREEN (PRIVATE) PLAY GROUND SURFACE WATER PERMIABLE PAVED AREA INFILTRATION GARDEN WADI GREEN ROOF (EXTENSIVE) GREEN ROOF (INTENSIVE) SURPLUS WATER ON SITE

507280 38442.4 208539.3 19776 30771 96324 68529 16284 4618 19191 4805.3

% area

rainfall (in mts.)

100.00 0.06 7.58 41.11 3.90 6.07 18.99 13.51 3.21 0.91 3.78 0.95 0.00 0.00 0.00 0.00

rainfall (duration in hours)

rainfall received (in surplus water (in correction (convert to 0 cu.mts.) cu.mts.) if negative) 2 30436.8 2306.544 2268.10 2268.10 12512.358 7715.95 7715.95 1186.56 731.71 731.71 1846.26 1815.49 1815.49 5779.44 5297.82 5297.82 4111.74 -3769.10 0.00 977.04 -895.62 0.00 277.08 207.81 207.81 1151.46 1151.46 1151.46 288.318 -110.52 -110.52 0 0.00 0.00 0 0.00 0.00 0 0.00 0.00 0 0.00 0.00 17926.36

10% of asphalt converted to semi permiable paving - 4805.3 sq.mts.

10% of asphalt converted to paved area - 4805.3 sq.mts. water absorbed/stored - 499.76 cu.mts.

CONCLUSION converting 10% of asphalt into semi permiable paving and 10% into paved surface aborbs/stores 2.7% of total surplus water

24

Measure three Converting 10% of asphalt into semi permiable paving Converting 10% of asphalt into paved surface area

Asphalt road

Paved surface

Semi permiable surface 2.7% 18426.12 cu.mts of surplus water

499.76 cu.mts of water stored/absorbed

25

Measure four Converting 20% paved surface into green

Paved surface

26

18426.12 cu.mts of surplus water

WATER ASSIGNMENT - RUBROEK, ROTTERDAM (measure 4 - 20% paved into green) AREA (sq.mts.)

TOTAL AREA ASPHALT ROAD PAVED AREA PAVED PARKING GABLE ROOFS FLAT ROOFS GREEN (PUBLIC) GREEN (PRIVATE) PLAY GROUND SURFACE WATER PERMIABLE PAVED AREA INFILTRATION GARDEN WADI GREEN ROOF (EXTENSIVE) GREEN ROOF (INTENSIVE) SURPLUS WATER ON SITE

507280 48053 162987.2 19776 30771 96324 109275.8 16284 4618 19191

% area 100.00 9.47 32.13 3.90 6.07 18.99 21.54 3.21 0.91 3.78 0.00 0.00 0.00 0.00 0.00

rainfall (in mts.)

rainfall (duration in hours)

0.06

rainfall received (in surplus water (in correction (convert to 0 cu.mts.) cu.mts.) if negative) 2

30436.8 2883.18 9779.232 1186.56 1846.26 5779.44 6556.548 977.04 277.08 1151.46 0 0 0 0 0

2835.13 6030.53 731.71 1815.49 5297.82 -6010.17 -895.62 207.81 1151.46 0.00 0.00 0.00 0.00 0.00

2835.13 6030.53 731.71 1815.49 5297.82 0.00 0.00 207.81 1151.46 0.00 0.00 0.00 0.00 0.00 16918.48

20% of paved area converted into green - 40746.8 sq.mts. water absorbed/stored - 1507.64 cu.mts.

CONCLUSION converting 20% of paved area into green aborbs/stores - 8.18% of total surplus water

27

Measure four Converting 20% paved surface into green

Paved surface Green area 8.18%

28

18426.12 cu.mts of surplus water

1507.64 cu.mts of water stored/absorbed

Measure five Introducing water storage tanks below playgrounds

Playgrounds

18426.12 cu.mts of surplus water

29

WATER ASSIGNMENT - RUBROEK, ROTTERDAM (measure 5 - water storage under play grounds) AREA (sq.mts.)

TOTAL AREA ASPHALT ROAD PAVED AREA PAVED PARKING GABLE ROOFS FLAT ROOFS GREEN (PUBLIC) GREEN (PRIVATE) PLAY GROUND SURFACE WATER PERMIABLE PAVED AREA INFILTRATION GARDEN WADI GREEN ROOF (EXTENSIVE) GREEN ROOF (INTENSIVE) SURPLUS WATER ON SITE

507280 48053 203734 19776 30771 96324 68529 16284 4618 19191

% area 100.00 9.47 40.16 3.90 6.07 18.99 13.51 3.21 0.91 3.78 0.00 0.00 0.00 0.00 0.00

rainfall (in mts.)

rainfall (duration in hours)

0.06

area of playgrounds - 4618 sq.mts.

1 mt. deep tank total water stored - 4618 cu.mts. balance water - 13808.12 cu.mts.

CONCLUSION introducing storage tanks under playgrounds can store 25% of total surplus water

30

rainfall received (in surplus water (in correction (convert to 0 cu.mts.) cu.mts.) if negative) 2

30436.8 2883.18 12224.04 1186.56 1846.26 5779.44 4111.74 977.04 277.08 1151.46 0 0 0 0 0

2835.13 7538.16 731.71 1815.49 5297.82 -3769.10 -895.62 207.81 1151.46 0.00 0.00 0.00 0.00 0.00

2835.13 7538.16 731.71 1815.49 5297.82 0.00 0.00 207.81 1151.46 0.00 0.00 0.00 0.00 0.00 18426.12

Measure five Introducing water storage tanks below playgrounds

Water tanks below playgrounds

25% 18426.12 cu.mts of surplus water

4618 cu.mts of water stored/absorbed

31

Measure six Introducing surface water with 50 cm depth

Existing green

32

18426.12 cu.mts of surplus water

WATER ASSIGNMENT - RUBROEK, ROTTERDAM (measure 6 - introducing surface water with 50 cm depth) AREA (sq.mts.)

TOTAL AREA ASPHALT ROAD PAVED AREA PAVED PARKING GABLE ROOFS FLAT ROOFS GREEN (PUBLIC) GREEN (PRIVATE) PLAY GROUND SURFACE WATER PERMIABLE PAVED AREA INFILTRATION GARDEN WADI GREEN ROOF (EXTENSIVE) GREEN ROOF (INTENSIVE) SURPLUS WATER ON SITE

507280 48053 203734 19776 30771 96324 68529 16284 4618 19191

% area 100.00 9.47 40.16 3.90 6.07 18.99 13.51 3.21 0.91 3.78 0.00 0.00 0.00 0.00 0.00

rainfall (in mts.)

0.06

rainfall (duration in hours)

rainfall received (in surplus water (in correction (convert to 0 cu.mts.) cu.mts.) if negative) 2

30436.8 2883.18 12224.04 1186.56 1846.26 5779.44 4111.74 977.04 277.08 1151.46 0 0 0 0 0

2835.13 7538.16 731.71 1815.49 5297.82 -3769.10 -895.62 207.81 1151.46 0.00 0.00 0.00 0.00 0.00

2835.13 7538.16 731.71 1815.49 5297.82 0.00 0.00 207.81 1151.46 0.00 0.00 0.00 0.00 0.00 18426.12

area of surface water - 2890 sq.mts. volume stored - 1445 cu.mtrs. balance surplus water - 16981.12 cu.mtrs CONCLUSION introducing surface water with 50 cm depth stores 7.8% of total surplus water

33

Measure six Introducing surface water with 50 cm depth

Existing green Surface water with 50 cm depth 7.8%

34

18426.12 cu.mts of surplus water

1445 cu.mts of water stored/absorbed

Measure seven Introducing surface water with 20 cm depth

Existing green

18426.12 cu.mts of surplus water

35

WATER ASSIGNMENT - RUBROEK, ROTTERDAM (measure 7 - surface water with 20 cm depth) AREA (sq.mts.)

TOTAL AREA ASPHALT ROAD PAVED AREA PAVED PARKING GABLE ROOFS FLAT ROOFS GREEN (PUBLIC) GREEN (PRIVATE) PLAY GROUND SURFACE WATER PERMIABLE PAVED AREA INFILTRATION GARDEN WADI GREEN ROOF (EXTENSIVE) GREEN ROOF (INTENSIVE) SURPLUS WATER ON SITE

507280 48053 203734 19776 30771 96324 68529 16284 4618 19191

% area

rainfall (in mts.)

100.00 0.06 9.47 40.16 3.90 6.07 18.99 13.51 3.21 0.91 3.78 0.00 0.00 0.00 0.00 0.00

area of surface water -7900 sq.mts. volume stored - 1580 cu.mtrs. balance surplus water - 16846.12 cu.mtrs CONCLUSION introducing surface water with 20 cm depth stores 8.5% of total surplus water

36

rainfall (duration in hours)

rainfall received (in surplus water (in correction (convert to 0 cu.mts.) cu.mts.) if negative) 2 30436.8 2883.18 2835.13 2835.13 12224.04 7538.16 7538.16 1186.56 731.71 731.71 1846.26 1815.49 1815.49 5779.44 5297.82 5297.82 4111.74 -3769.10 0.00 977.04 -895.62 0.00 277.08 207.81 207.81 1151.46 1151.46 1151.46 0 0.00 0.00 0 0.00 0.00 0 0.00 0.00 0 0.00 0.00 0 0.00 0.00 18426.12

Measure seven Introducing surface water with 20 cm depth

Existing green Surface water with 20 cm depth 8.5% 18426.12 cu.mts of surplus water

1580 cu.mts of water stored/absorbed

37

Measure eight Introducing storage tanks below green

Existing green

38

18426.12 cu.mts of surplus water

WATER ASSIGNMENT - RUBROEK, ROTTERDAM (measure 8 - water storage tanks) AREA (sq.mts.)

TOTAL AREA ASPHALT ROAD PAVED AREA PAVED PARKING GABLE ROOFS FLAT ROOFS GREEN (PUBLIC) GREEN (PRIVATE) PLAY GROUND SURFACE WATER PERMIABLE PAVED AREA INFILTRATION GARDEN WADI GREEN ROOF (EXTENSIVE) GREEN ROOF (INTENSIVE) SURPLUS WATER ON SITE

507280 48053 203734 19776 30771 96324 68529 16284 4618 19191

% area 100.00 9.47 40.16 3.90 6.07 18.99 13.51 3.21 0.91 3.78 0.00 0.00 0.00 0.00 0.00

rainfall (in mts.)

0.06

rainfall (duration in hours)

rainfall received (in surplus water (in correction (convert to 0 cu.mts.) cu.mts.) if negative) 2

30436.8 2883.18 12224.04 1186.56 1846.26 5779.44 4111.74 977.04 277.08 1151.46 0 0 0 0 0

2835.13 7538.16 731.71 1815.49 5297.82 -3769.10 -895.62 207.81 1151.46 0.00 0.00 0.00 0.00 0.00

2835.13 7538.16 731.71 1815.49 5297.82 0.00 0.00 207.81 1151.46 0.00 0.00 0.00 0.00 0.00 18426.12

area of green - 2761 sq.mts.

1 mt. deep tank total water stored -2761 cu.mts. balance water - 15665.12 cu.mts.

CONCLUSION introducing storage tanks under greens can store 14.9% of total surplus water

39

Measure eight Introducing storage tanks below green

Existing green Storage tank 14.9%

40

18426.12 cu.mts of surplus water

2761 cu.mts of water stored/absorbed

All measures combined map

Legend

Green area (public) Green area (private) Water (canals) New Paved surface Asphalt surface New green roofs Surface water Playgrounds with water tanks below them Gable roof

10 0

70 30

41

WATER ASSIGNMENT - RUBROEK, ROTTERDAM (sum of all measures) AREA (sq.mts.)

TOTAL AREA ASPHALT ROAD PAVED AREA PAVED PARKING GABLE ROOFS FLAT ROOFS GREEN (PUBLIC) GREEN (PRIVATE) PLAY GROUND SURFACE WATER PERMIABLE PAVED AREA INFILTRATION GARDEN WADI GREEN ROOF (EXTENSIVE) GREEN ROOF (INTENSIVE) SURPLUS WATER ON SITE

507280 38442.4 20142.4 8899.2 30771 57794.4 75542.2 16284 4618 19191 13704.5 10000 38529.6

% area

rainfall (in mts.)

100.00 0.06 7.58 3.97 1.75 6.07 11.39 14.89 3.21 0.91 3.78 2.70 0.00 1.97 7.60 0.00

rainfall (duration in hours)

asphalt - 10% semi permiable and 10% paved paved - 20% green parking - 10% green 50% of balance parking to semi permiable 40% of flat roof to green roof all play grounds have water storage 1 mt. deep introducing surface water with 50 cm depth introducing surface water converting greens to adaptable water storages of depth 20 cm storage tanks below wadi of depth 1 mt. balance of surplus water

42

rainfall received (in surplus water (in correction (convert to 0 cu.mts.) cu.mts.) if negative) 2 30436.8 2306.544 2268.10 2268.10 1208.544 745.27 745.27 533.952 329.27 329.27 1846.26 1815.49 1815.49 3467.664 3178.69 3178.69 4532.532 -4154.82 0.00 977.04 -895.62 0.00 277.08 207.81 207.81 1151.46 1151.46 1151.46 822.27 -315.20 0.00 0 0.00 0.00 600 300.00 300.00 2311.776 1926.48 1926.48 0 0.00 0.00 10771.11

4618 sq.mts.

2890 sq.mts.

7900 sq.mts.

2761 sq.mts.

4618 1445 1580 2761 367.11

Separating the run off from sewer public surface run off directed into sewer system

private

private

drainage pipe

Existing section

disconnected paved area private

groundwater level

community

over flow from private into community surface water drainage pipe

Separated system of drainage

private

The existing system within Rubroek neighborhood is a combined sewer system. The rainfall runoff from the roofs and paved or asphalt area is drained into the sewer system and further carried to treatment plants. The concept of closed city is to be applied to the Rubroek district in order to keep the water within the district. To do so, first important step to be taken is to separate the sewers.

The first section explains the existing combined sewer system with the runoff directed into the drains. The second section proposes to harvest the roof runoff within the private gardens. The approach is to infiltrate as much water as possible in the ground within the private realm. Further on saturation this water overflows into the community space. Rubroek neighborhood lacks the community spaces; it is either private gardens and backyards or public spaces. Another intention is to identify and demarcate these community spaces to develop a system of flow of water from private to public.

groundwater level

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Potential public spaces into community gardens Legend Green area (private) Green area (community) Green area (public) Water (canals)

10

44

0

70 30

Flow of water from private to public The framework for the strategy is to let water infiltrate at various points; starting from private grounds like water from roof can be infiltrated within the backyards.

Further, the overflow of the community space can go into the public green areas later diverted into the canal system in extreme case. Moreover, the groundwater also has a flow towards these canals.

The overflow from the backyards can be diverted into the newly introduced community spaces.

These green areas can be maintained by the housing blocks surrounding it. The nature of this green space can be of adaptive landscape which holds water during floods.

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Conclusions and reflection The study of Rubroek neighborhood in Rotterdam started with exploring the subsurface information using tool like EduGIS. Initial steps involved understanding the soil, groundwater, civil construction like cables and pipes, foundations, surface nature like paved, asphalt or vegetation, water management layers such as pressure pipes, valves, pumping stations, low areas and overflows. After mapping all these layers a subsurface potential map was developed to understand the potentials and limitations of the neighborhood.

The conclusion and observations drawn from the subsurface potential map were; first, the neighborhood has more than 51% of surface area as paved.

The rain water cannot infiltrate into the soil and all rainwater needs to be discharged into the sewer system. This was a second observation, Rubroek has a combined system. So as mentioned before the rainwater is discharged into the sewer system.

Every heavy shower increases the pressure on this water system. Streets get flooded due to insufficient discharge capacity.

The approach for Rubroek is developed on these two pointers; increase the infiltration area within the neighborhood to keep water within the area and separate the sewer system and rainwater runoff. Using tool like water assignment table amount of surplus water was calculated for a rainfall event of 60 mm in 2 hours. Based on this volume of water, number of measures were taken to understand

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which measure on individual bases has how much capacity to hold water. Later, combination of all measure were taken as a scenario to see how much and where Rubroek can hold water within its area.

A very important observation was marked after this exercise, most of the measures fall in the public realm, moreover Rubroek as a neighborhood has either private gardens and backyards or public greens. The exercise suggested that Rubroek requires an intermediate space between private and public to accommodate water and get the residents involved in the process.

It was interesting to observe for the project, how it started from subsurface exploration which led to water assignment and water calculations, which further pointed out some of the potential design elements which not only address the water issue but also address the social aspect in the neighborhood.

References Artificial vs natural - dr. F.L. Hooimeijer, lecture, 2016 Intelligent use of subsurface infrastructure for surface quality – Special project DIMI, dr. ir. Frans van de Ven, dr. ir. Francois Clemens, dr. ir. Wout Broere, dr. Susanne Laumann, dr. Renate Klaassen, ir. Aldert Kamp, Caterina Marinetti, editors – dr. F.L. Hooimeijer, dr. ir. T.K. Bacchin, Filippo Lafleur, Delft University of Technology

Water management in urban areas – Design SUDS – Dr. ir. Frans H.M. van de Ven, Delft University of Technology, March 2016 Water management in urban areas – Design water assignment - Dr. ir. Frans H.M. van de Ven, Delft University of Technology, March 2016 http://www.gis.rotterdam.nl/gisweb2/default.aspx - website

Performative nature – Taneha Bacchin, PhD, department of urbanism and department of water science and engineering, Delft University of Technology, December 2015 Rain, catch it if you can – Anne Witteveen, Master Thesis, urbanism department, Delft University of Technology, December 2014 Soil information - Jeroen Vuijk, Projectvoorbereider, Gemeente Rotterdam, Stadsontwikkeling, Millieu, Ruimte & Ondergrond, GIS & Datamanagement Study on the development of a Climate-proof Rubroek - 2014 - Peter Arnts, Technical Trainee Municipality of Rotterdam Water Department | urban Rotterdam Using subsoil in urban design process – Peter van der Graaf, Master Thesis, urbanism department, Delft University of Technology, December 2014

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