Blue Green Solutions

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Blue Green Solutions Guide

Urban planners and local governments are 

working to address these challenges. Many 

recognise that bringing Nature Based Solutions 

into the city is a powerful remedy for alleviating 

urban pressures and achieving resiliencetoclimate 

change. 

Proven benefits of Nature Based Solutions

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include reduction of surface flooding risk, water 

and air pollution, mitigation of flood risk and 

urban heat islands, increased resource efficiency, 

as well as provision of areas for recreation /

amenity and urban agriculture. A key advantage 

is that being vegetation based, their construction 

and operation has a low carbon and materials 

footprint. Other benefits include adding financial 

and aesthetic value to property, job creation, 

reducing building running costs and improving 

health and insurance premiums. 

However, at present we are not getting the best 

out of Nature Based Solutions (NBS), neither for 

new developments, nor retrofits. NBS are often 

used in a mono-functional way, e.g. to provide 

shading or detain stormwater runoff, or simply 

for their aesthetic value. Moreover, they are 

usually valued only in terms of their benefits to 

the developer/principal stakeholder(s).

In fact, a key advantage of NBS is that they 

can provide multiple benefits to multiple 

stakeholders. Many of these co-benefits only 

arise when NBS are planned so as to utilise their 

beneficial interactions (synergies) with the local 

urban environment. The challenge therefore, 

both for new developments and for retrofits, is 

to enable current urban planning practice to map 

and exploit the synergistic benefits of NBS.

The Climate-KIC Innovation project Blue Green 

Dream (2012-2015), led by Imperial College 

London, initiated a step-change in how we map 

and exploit the potential benefits of NBS. A 

key focus was the use of NBS to achieve urban 

sustainability and climate change resilience. What 

really set the Blue Green Dream project apart 

from other NBS (especially, green infrastructure) 

projects were two key innovations: 

Its holistic, integrated planning 

methodology,   which entails engaging 

with a wide panel of stakeholders across 

the whole planning process. 

The concept of modelling, quantifying and 

optimising potential synergies between 

NBS, local water resources, the local built 

environment and climate, innovations 

in urban design and architecture, etc., 

to achieve lower life-cycle costs and 

enhanced benefits.  

The Blue Green Dream project was awarded the 

Business Green Technology Award for Research 

and Development Programme of the Year

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. 

This guide presents the integrated planning 

methodology developed from the Blue Green 

Dream Project, referred to hereafter as the Blue-

Green (BG) Systems approach. 

We showcase several case studies, each 

demonstrating a different element of our 

approach.  The case studies show that through 

applying this holistic, quantitative approach to 

their planning and design, NBS can be highly cost-

effective. Not only do they increase the value 

of developments, but they deliver substantial 

savings in operational costs.  

This guide contributes to Climate-KIC’s ‘urban 

transitions’ work, demonstrating its novel 

approaches to creating low carbon and resilient 

cities.

2 Blue Green Solutions for Urban 

Transition  

Increasing urbanisation, climate change and 

extreme weather conditions are resulting in 

increased urban stresses. These include water 

and air pollution and resource scarcity, all of which 

are reducing urban liveability. Adaptation to, and 

mitigation of these pressures is a major concern 

at EU and international levels.  

Initially, Nature Based Solutions (NBS)

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 such 

as green roofs and walls, rain gardens, swales, 

etc., were conceived as a means of both locally 

managing rainfall (surface) runoff and improving 

amenities. Such interventions are commonly 

termed Sustainable Urban Drainage Systems 

(SUDS) 

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. More recently, macro-scale concepts 

such as Water Sensitive Urban Design (WSUD) 

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, 

have enhanced and broadened the SUDS concept 

by recognising the role that NBS can play in 

holistically managing urban water resources.  

The Blue Green Dream (BGD) project 

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 built 

upon and expanded the SUDS and WSUD 

Historical development of Blue Green Solutions (BG-S) via SUDS and WSUD 

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concept (Figure 2) to produce a systematic

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quantitative framework for utilising the full range 

of ecosystem services that NBS provide, yielding 

Blue Green (BG) Solutions. Within the urban 

context ecosystem services provide a means of 

mitigating not only for water related problems, 

but also for urban development pressures such 

as heat islands, air pollution, resource scarcity etc. 

(Figure 3).

A range of successful examples of the 

implementation of associated aspects of the 

NBS concept exist worldwide. These include: the 

Gardens by the Bay, Singapore

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; the High Line 

Park, New York

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; the Blue Green Wave, Paris 

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; 

City Park, Budapest

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 ; the Village Nature Resort, 

Paris

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; the Multifunctional Urban Water System 

in Lindenhof in Berlin-Lichtenberg; Curitiba city, 

Brazil

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; the Multifunctional roof garden and 

campus, Yuntou Co, China; the Wild West End 

project, London

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; and the Smart Sustainable 

Districts development, Utrecht

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.

Water

Supply City

Sewered

City

Drained

City

Waterway

City

Water Cycle

City

Water Sensitive

City

Blue Green

Dream

SUDS

WSUD

BG-S

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2012

1990

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