Green Infrastructure in
Birmingham city centre
MSc Thesis Project - Aisling Mannion
Aims
The aims of this project are to:
• Map the existing green infrastructure (GI)
• Plan potential future GI
• Assess the benefits of GI
The study area
Canal
ICC
Town Hall
Canal
Birmingham Cathedral
New Street Station
Millennium Point
Canal
The need for GI
Predicted climate change
• Summer mean temperature in the West
Midlands is predicted to increase by 3.7°C by the
2080s.
• Urban Heat Island effect may add an extra 3°C.
• Winter precipitation in the West Midlands is
predicted to increase by 17% by the 2080s.
The need for GI
Risks from climate change
• High temperature increases air pollution
• Higher risk of flooding & flood damage
• Urban areas exacerbate temperature and flood
risks
• Damage to health & higher healthcare costs
• Higher energy use for cooling & energy costs
The need for GI
Air quality in Birmingham
• GI can help to meet EU standards
• Air quality needs to improve for health reasons
Image and investment in Birmingham
• GI can improve Birmingham’s reputation
• GI can increase visitor numbers and revenue in
rundown areas.
• GI can make Birmingham more attractive to investors
& skilled workers
Existing GI in Birmingham city centre
Existing GI in Birmingham city centre
Existing GI in Birmingham city centre
Grass, shrubs, flowerbeds
21 ha
Water
4 ha
Trees
1,120
Green roofs
0.2 ha
Total roof area
99.5 ha
Green roofs (% of all roofs)
0.2 %
Impermeable surface area
90%
Potential GI in Birmingham city centre
Birmingham city centre is densely urbanised.
Suitable methods for increasing GI here are:
– street trees
– green roofs
– green walls
– improving existing parks
– SuDS
– restoring existing water courses
– linking existing green spaces
Plan for potential GI
The focus is on a route for pedestrians, to connect areas of existing GI
Canal
Town Hall
ICC
Birmingham Cathedral
New Street Station
Millennium Point
Canal
Potential GI in Birmingham – street level
Potential GI in Birmingham – street trees
Curzon Street
Chamberlain Square
The Bullring
Centenary Square
Victoria Square
Square by the REP
Potential GI in Birmingham – green roofs
Potential GI in Birmingham – green roofs
Extensive green roof,
Canary Wharf, London
Semi-intensive green roof, Chicago
Intensive green roof,
Kensington Roof Gardens, London
Brown roof,
Fire & Rescue Authority, Birmingham
Potential GI in Birmingham – green walls
Potential GI in Birmingham – green walls
Potential GI in Birmingham
Grass, shrubs, flowerbeds
26 ha
Water
4 ha
Trees
2,090
Green roofs
32ha
Total roof area
99.5 ha
Green roofs (% of all roofs)
32 %
Impermeable surface area
70%
Benefits of Green Infrastructure
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Mitigates the Urban Heat Island effect
Improves air quality
Reduces surface runoff
Improves health
Reduces energy usage for cooling and heating
Improves image and investment
Improves ecology and biodiversity
Provides economic savings
Benefits of Green Infrastructure Indicative results
Air quality
• Potential green roofs cover 32 ha
– All extensive: removes 2700 kg/yr of air pollutants.
– All intensive: removes 3500 kg/yr of air pollutants. (Yang, 2008)
• Trees: Pollution removal rate 10.8 g/m2/yr.
(Nowak, 2006)
– 2000 trees may remove over 112kg.
Benefits of Green Infrastructure Indicative results
Energy savings
• Potential energy savings from green roofs of
4.15kWh/m2/yr. (Banting, 2005)
• 32 ha of green roofs may save 1.3GWh/yr.
Benefits of Green Infrastructure Indicative results
Reduction of surface runoff
• A typical medium-sized tree can intercept 9000 litres of
rainfall per year. If the tree canopy spans 9m2, then this
represents an annual rainfall depth of 1 m.
• Green roofs have a water storage capacity of 30 – 140
litres/m2
• Total potential water storage of 9.7 million – 45 million litres
on green roofs in Birmingham city centre.
Thank you for listening!