Session description - Resilient Cities 2015

SESSION DESCRIPTION
E3
Green and gray infrastructure solutions for
enhancing resilience to urban flooding
Workshop
Date: Tuesday, 9 June, 2015
Time: 16:45-18:15
Rooms: S34-35
Language:
Contact:
E-mail/web:
Organized by:
English
Maija Bertule
mabe@dhigroup.com / www.dhigroup.com
ICLEI and UNEP-DHI
OBJECTIVE
Climate change impacts, as well as the related ecosystems responses, bear a high level of uncertainty
often making it challenging for decision-makers to define the ‘right’ choices. Planning for and building
future infrastructure that can adapt, and secure resilience to the growing populations in the light of
climate change is essential for the development of sustainable urban communities and the human wellbeing.
This workshop focused on ways and means to arrive at rational decisions on green infrastructure
solutions for resilient urban water systems, with a specific focus on managing urban flooding.
Participants learned about different criteria to assess green - or gray-green – infrastructure solutions,
practical tools for science-based decision-making under uncertainty and real-life opportunities and
challenges experienced in green infrastructure planning and implementation.
The session demonstrated its approach with two city case studies and reflected on useful tools for
quantifying green infrastructure and saving costs in urban flood protection. The city of Essen shared its
experience in planning and implementing green infrastructure solutions and discussed related
challenges and opportunities along the way. Ample time was also given for group discussion to identify
and share additional experiences from the audience.
OUTCOMES
Participants left the workshop session with:

Awareness on specific potential and benefits of selected green infrastructure solutions to
address climate change impacts in an urban context;

Awareness on available tools to support science-based decision-making for green and hybrid
(green-gray) infrastructure solutions in the face of uncertainty, including cost-benefit analysis;

Inspiration from participating city “case study” representatives on what kind of green
infrastructure solutions – including combinations of green and gray solutions – was useful for
them and why.
METHODOLOGY
Facilitator
Alice Reil, Officer, Sustainable Resources, Climate and Resilience, ICLEI European
Secretariat, Freiburg, Germany
16:45 – 16:50
The facilitator will make opening remarks and briefly introduce the program
16:50 – 17:05 Tools to support the decision-making processes in application of green (-gray)
solutions
Maija Bertule, Program Advisor, UNEP-DHI Partnership Denmark
17:05– 17:20 Integrating natural infrastructure into urban coastal resilience: Howard Beach,
Queens, New York, United States
Joel Paque, Policy Advisor, The Nature Conservancy, Arlington, United States
This presentation demonstrated how natural defenses, in conjunction with built
infrastructure, can help protect communities from the impacts of climate change. The
case study presented was focused on neighborhood scale protection alternatives and
offers a robust methodology that could be replicated and applied to other coastal
communities to evaluate the efficacy and relative costs and benefits of potential coastal
resilience strategies, utilizing both natural and built infrastructure.
17:20 – 17:35
Essen: A green city of North-Rhine Westphalia
Thomas Kleinebrahm, Officer, Environmental Agency, City of Essen, Germany; and
Kai Lipsius, Manager of Climate Protection, Environmental Agency, City of Essen
Green-blue infrastructure is the motor for Essen’s sustainable urban development.
Between 2007 and 2014, more than € 50 million were invested in green-blue
infrastructure. The city of Essen is creating a network of green areas and open spaces
based on the master plan “Open Space Creates City Space”. This network follows the
water bodies along the region’s three North-South axes, which connect the more
natural Ruhr Valley in the south with the industrial Emscher Valley. The city presented
a number of examples where it opted for green-blue and green-gray infrastructure
solutions; one of which is the restoration of the river Emscher. The conversion of the
Emscher system is the largest water body restoration project in Europe and will last
until 2020. Essen also demonstrated the multi-functionality of its projects, such as its
rainwater recovery measures. The objective within the Emscher catchment area is to
decouple 15% of the area connected to the combined sewer system.
17:35 – 18:05
Formation of 2 groups among participants to discuss options for green infrastructure
and hybrid infrastructure solutions, as well as opportunities and barriers to
implementation - (30 min.)
18:05 – 18:15 Presentation of ‘top results’ from group discussions (10 min)
18:10 - 18:15
Wrap-up and close of workshop
Further recommended reading
Green Infrastructure: Guide for Water Management
UNEP, 2014: Green Infrastructure Guide for Water Management: Ecosystem-based Management Approaches for
Water-Related Infrastructure Projects (2014)
UNEP_DHI
unep-dhi.org
SWITCH Training Kit: Integrated Urban Water Management in the City of the Future
Philip, R. et al: SWITCH Training Kit, Module 5: Waste Water – Exploring the options (2011)