Urban River Basin Enhancement · PDF fileUrban River Basin Enhancement Methods funded by European Commission 5 th Framework Programme, Key Action 4 “City of tomorrow and cultural

Urban River Basin Enhancement Methods

funded by

European Commission

5 th Framework Programme, Key Action 4 City of tomorrow and cultural heritage

Existing Urban River Rehabilitation Schemes

(Work package 2)

Final Report

Leibniz Institute of Ecological and Regional Development, Dresden (IOER)

Jochen Schanze, Alfred Olfert

Dresden University of Technology (TU Dresden)

Joachim T. Tourbier, Ines Gersdorf, Thomas Schwager

June 2004

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Further partners involved from the URBEM team

University of Agricultural Sciences Vienna (BOKU) Hubert Holzmann, Rudolf Faber

Portuguese National Civil Engineering Laboratory Joao Rocha

University of Ljubljana - Faculty of Civil and Geodetic Engineering Mitja Brilly

Javno podjete Vodovod-Kanalizacija (JP VO-KA) Drago Dolenc

Cemagref Parcel Breill

Centre for Urban Waters UK Cedo Maksimovic

Acknowledgement

This study has been funded as work package 2 of the URBEM research project by the European Commission under the 5th Framework Programme. The authors furthermore acknowledge Prof. Roger Bettess and Dr. Joao Rocha for their valuable review.

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URBEM Existing Urban River Rehabilitation Schemes IOER & TU Dresden

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Table of Contents

1 Introduction...................................................................................................................... 1

1.1 Urban River Rehabilitation and the URBEM project ....................................................... 1 1.2 Investigation of existing urban river rehabilitation schemes ........................................... 2 1.3 Baselines of urban water rehabilitation........................................................................... 3 1.4 Urban river rehabilitation in the European context.......................................................... 5

2 Approach .......................................................................................................................... 8

2.1 Survey and selection of case studies ............................................................................. 8 2.2 Standardised enquiry.................................................................................................... 11

3 Characterisation of the case studies ........................................................................... 13

3.1 Brief description of each case study ............................................................................. 14 3.2 Comparison of general characteristics ......................................................................... 21

4 Planning and implementation process........................................................................ 30

4.1 Initiation of urban river rehabilitation projects ............................................................... 30 4.2 Site selection ................................................................................................................ 32 4.3 Aspects of project management ................................................................................... 37 4.4 Site management and maintenance ............................................................................. 43

5 Rehabilitation techniques ............................................................................................. 45

5.1 Techniques to improve hydrology and hydrodynamics................................................. 46 5.2 Techniques to improve stream morphology and connectivity....................................... 47 5.3 Techniques to improve water quality ............................................................................ 53 5.4 Techniques to improve biodiversity .............................................................................. 55 5.5 Techniques to improve features of public health and safety......................................... 56

6 Impacts of river rehabilitation projects ....................................................................... 59

6.1 Ecological impacts ........................................................................................................ 60 6.2 Social and aesthetic impacts ........................................................................................ 66

7 Aesthetic evaluation methods...................................................................................... 76

7.1 State of the art .............................................................................................................. 76 7.2 Aspects of aesthetics considered in urban river enhancement .................................... 77 7.3 Applied aesthetic evaluation methods .......................................................................... 79

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8 Social appraisal and stakeholder involvement ........................................................... 84

8.1 Legal requirements for public participation ................................................................... 84 8.2 Stakeholders ................................................................................................................. 85 8.3 Informing stakeholders.................................................................................................. 88 8.4 Involving stakeholders in the process ........................................................................... 91 8.5 Stewardship and advocacy ........................................................................................... 96 8.6 Monitoring social impact ............................................................................................... 98

9 Performance control and indicators of success....................................................... 100

9.1 Definitions ................................................................................................................... 100 9.2 Performance control as practised ............................................................................... 102 9.3 Towards indicators of success for urban river rehabilitation ....................................... 108

10 Summary..................................................................................................................... 110

11 References.................................................................................................................. 113

12 Acknowledgements for contributions to the case studies .................................... 120

13 Annexes .......................................................................................................................... 1

Annex 1 Data enquiry form ..................................................................................................... 1 Annex 2 Description of techniques ......................................................................................... 1

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List of Figures

Figure 1: Objectives of urban river rehabilitation projects 23

Figure 2: Objectives of ecological improvement in urban rehabilitation projects 24

Figure 3: Urban pressures and pressures in case study areas 24

Figure 4: Width of rehabilitated water courses (classification by Huet 1949) 25

Figure 5: Lengths of rehabilitated sections 26

Figure 6: Length of rehabilitated sections of water courses and overall size of affected area 26

Figure 7: Total costs of urban rehabilitation projects 27

Figure 8: Total costs of urban river rehabilitation projects 28

Figure 9: Correlation of total project costs and the length of the rehabilitated section 28

Figure 10: Costs per meter of urban river rehabilitation projects 29

Figure 11: Initiators of urban river rehabilitation projects 31

Figure 12: Funding sources for urban river rehabilitation projects 38

Figure 13: Time frame for realisation of urban river rehabilitation projects 42

Figure 14: Time line of planning and implementation of urban river rehabilitation projects 42

Figure 15: Measures to improve stream hydrology and hydrodynamics 46

Figure 16: Measures to improve instream morphology 49

Figure 17: Measures to re-establish and to integrate flood plains 51

Figure 18: Measures improving continuity 52

Figure 19: Measures to improve water quality 54

Figure 20: Measures directly improving biodiversity 56

Figure 21: Measures to improve safety features 57

Figure 22: Biological conditions of urban waters before and after rehabilitation 60

Figure 23: Impact of urban river rehabilitation schemes on fish fauna 61

Figure 24: Impact of urban river rehabilitation schemes on benthic invertebrate fauna 61

Figure 25: Impact of urban river rehabilitation schemes on benthic macrophytes and phytobenthos 62

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Figure 26: Hydromorphological conditions of urban waters before and after rehabilitation 63

Figure 27: Impact of urban river rehabilitation schemes on morphological conditions 63

Figure 28: Impact of urban river rehabilitation schemes on river continuity 64

Figure 29: Impact of urban river rehabilitation schemes on hydrological regime 64

Figure 30: Conditions of chemical and physico-chemical components of urban waters before and after rehabilitation 65

Figure 31: Impact of urban river rehabilitation schemes on general conditions of physico-chemical