Europe’s urban spaces turning green
Publicado por Robert Brears el Jue, 12/01/2017 - 09:39
Europe is an urban and increasingly urban continent with the percentage of the population living in urban centers expected to increase from over 70% in 2015 to more than 80% in 2050.
This rate of urbanization will pose challenges to natural resources and ecosystems within urban areas including rivers, streams and lakes that are part of the landscape of European cities. Some of the key impacts of urbanization include:
Water quantity impacts with decreased flow and reduced groundwater levels as well as increased flow from surface runoff
Water quality impacts with increased surface runoff from impervious areas (roads, roofs, gardens etc.) along with stormwater overflows contaminating waterways
Increased flooding risks from waterways being straightened
Decreased habitats for wildlife
To reverse the impacts of urbanization, many cities in Europe have developed broad visions and strategies to promote a more integrated approach to managing their urban spaces and waterways, including the use of green infrastructure. Green infrastructure uses vegetation, soils and natural processes to manage excess water and create healthier environments for both humans and nature. In urban areas, green infrastructure ranges in size from permeable pavements, rain gardens and green spaces in neighborhoods all the way up to restored riverways at the city-level.
When green infrastructure is interconnected it can enhance the resilience of infrastructure and communities to extreme weather events by reducing localized flooding risks as well as improving water quality. These benefits are complemented by additional environmental, economic and social benefits including improved air quality, reduced urban temperatures, energy savings, higher property values, increased recreational opportunities and aesthetic improvements. Furthermore, green Infrastructure, unlike grey infrastructure, can appreciate in value over time with the regeneration of nature and its associated ecosystem services.
London’s river restoration
The restoration of the River Mayesbrook and its adjacent park in east London is a flagship project of the London Rivers Action Plan, which is the city’s first ever plan for restoring all of London’s rivers. Prior to its restoration, the area had run-down sports facilities, two polluted artificial lakes and a straightened, realigned and fenced river sunk into a deep concrete channel. In the Thames River Basin Management Plan 2009-2015 it was described as one of the worst water bodies in the area, failing to achieve good ecological potential because of its hydromorphological modifications, poor water quality and low ecology.
Sunset over Mayesbrook
A river restoration brings multiple benefits
The restoration focused on enhancing the community space in the area and creating a more natural landscape that at the same time could be a model for climate change adaptation in a city environment. The restoration measures included creating a new flood plain (1.5 ha) and establishing a river wetland as well as woodland planting. The project also created new sinuous water channels and regraded the riverbanks. In addition to the ecological benefits, the restoration of the river and surrounding area provides the community with multiple health and recreational benefits including increased quality of life, improved safety through greater park usage and a living lab for local schools. Overall, it is estimated that the benefit-to-cost ratio of the river restoration is GBP 7 of benefits for every GBP 1 of investment.
All-in-all, cities in Europe can reverse the impacts of urbanization by implementing green infrastructure projects that not only restore the health of ecosystems but also provide numerous social benefits.
Robert Brears (@Mitidaption)