u 0643700

8/17/2019 u 0643700

1/15

Restoration of urban rivers as a challenge towards sustainability

Are ecologic and social concerns compatible?

Expo Zaragoza 2008 Tribuna del Agua ST3 Agua para la Vida – Rios y Sostenibilidad

Are ecologic and social

Restoration of urban rivers

as

a challenge towards

sustainability.

concerns compatible?

Maria da Graça Amaral Saraiva

8/17/2019 u 0643700

2/15

Restoration of urban rivers as a challenge towards sustainability.Are ecologic and social concerns compatible?

Summary

• City- river relationships

• General overview on urban river rehabilitation

constraints and opportunities

• Some experiences - the URBEM project

• Assessment and evaluation - indicators for post

implementation assessment

•

Conclusions

8/17/2019 u 0643700

3/15

S. Paulo Dublin Coimbra


Moscow

Bilbao Boston Chicago

Rome Oporto

8/17/2019 u 0643700

4/15


Pressures and impacts

Opportunities - public interest and values

8/17/2019 u 0643700

5/15

European

the policies’ skyline...

WaterFramework

Directive


LandscapeConvention

Policy integration

LocalAgenda 21

Thematic strategy onurban environment

Urban sustainability

Urban quality of life

Landscape qualityWater quality

Environmental integrationUrban ecology

Ecological potential

cities rivers

8/17/2019 u 0643700

6/15


Examples of urban river rehabilitation and improvement

Stream daylighting in Leipzig, Germany Santa Rosa Creek, CA, USA

Rehabilitation of urban creeks, Gaia, PortugalRehabilitation of Jardas creek, Cacém, Portugal

8/17/2019 u 0643700

7/15

Enhancement means an improvement of the current state of riversand its surroundings. It aims at a general valorisation of the ecological,social, economic and aesthetic properties.

U r b a

n

r i v e r s


ConceptsRestoration is directed towards recreating the pristine physical,chemical and biological state of rivers. In its purest sense it means afull structural and functional return to a pre-disturbance state (Wade etal. 1998, p. 2).

Renaturalisation or naturalisation describes the naturalistic way ofbringing a (river-) ecosystem back to a natural state but withouttargeting the really pristine, pre-disturbance state (cp. Mendiondo1999).

Rehabilitation indicates a process which can be defined as the partialfunctional and/or structural return to a former or pre-degradationcondition of rivers or putting them back to good working order(Wade at al. 1998, p. 2). It is dedicated to the ecologic state

(biological, hydromorphological and physico-chemical) by structuraland partly non-structural measures.

8/17/2019 u 0643700

8/15


•

artificialization of urban fluvial systems - “highly modified water bodies”•

restrictions imposed by urban uses

• pollution and decrease water quality

• high rate of imperviousness and runnof• flood risks

•

loss of biodiversity and landscape quality• growing public interest on riverine and riverfront areas•

opportunities for rehabilitation associated to urban regeneration processes

“restoration in urban streams is both more expensive and more difficultthan in less densely populated catchments ” (Giller, 2005)

8/17/2019 u 0643700

9/15


URBEM WP2 Survey on existing Urban River Rehabilitation Schemes,Schanze et al., 2004

Objectives of urban river rehabilitation projects

n a m e d o b j e c t i v e s o f u r b a n r i v e r

r e h a b i l i t a t i o n

p r o j e c t s

flood control

ecological improvement

visual improvement

amenity/recreation

urban upgrading

Public involvement

education

others

9 (39%)

22 (96%)

6 (26%)

10 (43%)

10 (43%)

8 (35%)

5 (22%)

8 (35%)

0 5 10 15 20

number of namings (n=23)

Urban River Basin Enhancement Methods

2002-2005 www.urbem.net

8/17/2019 u 0643700

10/15


Urban constraints and pressures in case study areas

u r b a n p r e s s u r e s p r e v a i l i n g i n

t h e c a s e s t

u d y a r e a s

f lood def ence

spatial constraints

channelization

competing land uses

hy drologic regime

water quality

statutory constraints

other

8 (35 %)

11 (48 %)

16 (70 %)

4 (17 %)

3 (13 %)

6 (26 %)

10 (43 %)

7 (30 %)

0 5 10 15

* as ref ered to in the enquiry process, not explicitly enquired number of namings*

Objectives of ecological im provem ent

in urban rehabilitation projects

Schanze et al., 2004

8 (36%)

7 (32%)

11 (50%)

5 (23%)

5 (23%)

6 (27%)

2 (9%)

3 (14%)

0 2 4 6 8 10 12 14

other parameters

v egetation

target species

lateral connectiv ity

continuum

stream morphology

hy drlology / hy daulics

water quality

n a m e d o b j e c t i v e

s o f

e c o l o g c a l e n h a n c

e m e n t

number of namings (n=22)

8/17/2019 u 0643700

11/15

Cultural events Pollution by all priority substances identified as being

discharged

into

the

body

of water

Integration of cultural heritage and cultural assets

Hydromorphological conditions (WFD)

Recreational

paths

Width

of

riparian

fringe

Recreational facilities Presence of riparian vegetation

Landmarks / Viewpoints River continuity

Public

utility

of

river

sites

Connection

to

groundwater

bodies

River

crossings

Use

of

recicled

water

Anchorage points Percentage of stream length with riparian vegetation

Water

contact

zones

Inundability

Unemployment Access points for soft modes Acididification status

Median property value Public transportation stops River depth and width variation

Activities to create income Parking lots Biological water quality (WFD)

Economic Indicators Social Indicators Ecological Indicators


IndicatorsofSuccess,Tourbie

retal.,2005

8/17/2019 u 0643700

12/15

R E A B I L I T A Ç Ã O D E S I S T E M A S R I B E I R I N H


O

S

Case Study - Evaluation of the rehabilitation of river Fervença

at Bragança,

, POLIS Programme, Portugal

ECOLOGIC SOCIAL/URBAN ECONOMIC

Qualidade da Água +

Biodiversidade -

Galeria rípicola -

Estrutura Verde --

Gestão de Riscos

Conforto Bioclimático

Qualidade de Vida

Recreio e Lazer ++

Identidade ++

Satisfação ++

Integração Cidade – Rio

Mobilidade

Oportunidade de negócio 0

Auto-sustentação do espaço 0

Serviços/Equipamentos +

8/17/2019 u 0643700

13/15

Stability of the land-use management system ; Ex istence of projects or

programmes w ith influence over the riverfront; Compatibility/conflictsbetw een different management instruments. Public involvement andparticipation.

8 Governance and sustainable

management

Social facilit ies area on the riverf ront per inhabitant; Percentage of openpublic space on the riverfront; Area of restaurants, commerce and otherservices available for recreation over total surface area of the riverfront.

7 Availability of local publicspaces and services

River crossings for pedestrians; Accessibility to the river on publictransports.

6 Mobility and river accessibility

% of impervious surfaces in urban w atersheds;5 Sustainable land use

Risk = Probability (probability of chain of events f rom origin to impact) xExposure x Vulnerability (consequences/damages).

4 Flood risk

Riparian corridor conservation status; Ecological status of w ater bodies.3 Ecological quality of the rivercorridor

Variables measurements of climate (temperature, relative humidity,w ind speed (direction), solar radiation).

2 River contribution to localbioclimatic change

Satisfaction Level of the citizens in relation to the intervention area.1 Citizen satisfaction with thelocal riverfront

MEASURESRIPROCITY INDICATORS


R i P r o

C i t y P r o j e c t

R i v e r s a n d

c i t i e s : o p p o r t u n i t i e s f o r u r b a n s u s t a i n a b i l i t y

8/17/2019 u 0643700

14/15

Rio Tejo Lisboa


2nd generation

3rd generation Public spaceEnvironmental

and ecologicrehabilitation

with social

concerns?

Thames River, Londres

1st generation

Riverfront development

8/17/2019 u 0643700

15/15


Multidisciplinarity....

and publicinvolvement and

participation.....

Documents

u 0643700