Flandre: adaptation du code de l’urbanisme en l’outil
watertoets
Ingeborg Barrez – VMM – Afdeling Ecologisch Toezicht
CONTENTS
– Findings
– Policy
– Legislation
• Urban development act
• Code of good practices
• Water assessment
– Tools
• Real estate
• Rainwater Blueprint
• Publications
http://environnement.wallonie.be/directive_eau
CONTENTS
– FINDINGS
– Policy
– Legislation
• Urban development act
• Code of good practices
• Water assessment
– Tools
• Real estate
• Rainwater Blueprint
• Publications
http://environnement.wallonie.be/directive_eau
Finding: 1. Overflow of waste water
http://environnement.wallonie.be/directive_eau
Finding: 2. Dilution of wastewater
http://environnement.wallonie.be/directive_eau
Finding: 3. Peakload in sewersytem and
watercourse
http://environnement.wallonie.be/directive_eau
Finding: 4. Forecast climate change
• Current problems will increase
– Climate change
– Returnperiod halves against 2050
http://environnement.wallonie.be/directive_eau
Finding: 5. Space development
Increase development
increase floodrisk
http://environnement.wallonie.be/directive_eau
FINDINGS: CONCLUSION
Lack of measures has a negative impact on
– Waterquality
– Overflowfrequency
– Lack of inflitration
http://environnement.wallonie.be/directive_eau
CONTENTS
– Findings
– POLICY
– Legislation
• Urban development act
• Code of good practices
• Water assessment
– Tools
• Real estate
• Rainwater Blueprint
• Publications
http://environnement.wallonie.be/directive_eau
Policy
• European Legislation
– European Water Framework Directive
• good general status of the surface water and ground water
– Floods Directive
• reduce and manage the risks of floods
http://environnement.wallonie.be/directive_eau
Policy
Flemish government 2009-2014
• Adjust the urban development act and code of good practices
• Reduce and manage the risks of floods
• Measures on the source
http://environnement.wallonie.be/directive_eau
POLICY
• Policy document 2014-2019 – Minister Schauvliege
– Avoid additional pavement
– Avoid sealing of the soil
• Water Policy document (WFD)
– Apply the strategy ‘retain – store – drain away’ on the field
– (re) use, infiltration and storage of rainwater are our guarantee of
source directed measures
– Ensure room for water
http://environnement.wallonie.be/directive_eau
http://environnement.wallonie.be/directive_eau
CONTENTS
– Findings
– Policy
– LEGISLATION
• Urban development act
• Code of good practices
• Water assessment
– Tools
• Real estate
• Rainwater Blueprint
• Publications
http://environnement.wallonie.be/directive_eau
LEGISLATION
– Urban development act : private domain
– Code of good practices: public domain
– Water assessment
http://environnement.wallonie.be/directive_eau
Legislation: Urban development act
• Coverd constructions and paving with permission or duty to
report
• Exemptions
– Infiltration on private domain (no drains)
– Polluted surfaces
waste water
– Public domain
http://environnement.wallonie.be/directive_eau
Legislation: Urban development act
• (Re)Use
– Family homes (single) (up 40m²): min. 5.000 l
– Other constructions (up 100 m²): 50 l/m² - max. 10.000 l
http://environnement.wallonie.be/directive_eau
Legislation: Urban development act
• Infiltration
– Always obliged!
• 25 l/m² run-off surface.
• 4 m² per 100 m² run-off surface.
– Exemptions
• Protection area I en II (groundwater)
• Property < 250 m²
• Infiltration impossible (motivation!)
http://environnement.wallonie.be/directive_eau
Legislation: Urban development act
• Storage
– Area < 2.500 m²
• Min. 25 l/m² run-off surface
– Area > 2.500 m²
• Min. 25 l/m² run-off surface
• Drainage flow rate max. 20 l/s/ha
http://environnement.wallonie.be/directive_eau
Legislation: Urban development act
• Allotment
– The same principles as for surfacing
infiltration!!
– Take into account a extra area of 80 m² per lot
– Regulations on individual parcels remain in force
http://environnement.wallonie.be/directive_eau
LEGISLATION: CODE OF GOOD PRACTICES
http://environnement.wallonie.be/directive_eau
Legislation: code of good practices
Step 1: Avoid run-off
Natural situation
Reuse dikes
Step 2 : Infiltration
Area without risk of flooding
Area with risk of flooding
Step 3 : Store
http://environnement.wallonie.be/directive_eau
LEGISLATION: WATER ASSESSMENT
– An instrument to assess possible hazardous effects of
permits, plans or programs on the water system
• Obligation to ask advice in advance in certain cases
• Results in a water paragraph in the decision (permits, plans or
programs)
– How? A step-by-step approach
1. Hazardous
effect: yes/no?
2. Conditions to
prevent or
minimise
http://environnement.wallonie.be/directive_eau
3. Conditions to
remediate or
compensate
4. Refuse
LEGISLATION: WATER ASSESSMENT
- Tools?
• Guidelines
• Internet tool
www.watertoets.be
• Training for users
http://environnement.wallonie.be/directive_eau
CONTENTS
– Findings
– Policy
– Legislation
• Urban development act
• Code of good practices
• Water assessment
– TOOLS
• Real estate
• Rainwater Blueprint
• Publications
http://environnement.wallonie.be/directive_eau
TOOLS: Real estate
Obligation to provide information on flood prone areas in
publicity and in private and notarial acts
http://environnement.wallonie.be/directive_eau
TOOLS: rainwater blueprint
RAINWATER BLUEPRINT
BASIC
DETAIL
PLAN OF REALIZATION
• Map
• Big areas
• Defining
• Zones of infiltration
• Rainwater drains
• Bottle necks
• Rough copy
• Street/property level
• Modelling
• Who
• What
• When
http://environnement.wallonie.be/directive_eau
TOOLS: Publications
http://environnement.wallonie.be/directive_eau
www.vmm.be
www.integraalwaterbeleid.be
http://environnement.wallonie.be/directive_eau
Merci pour votre attention