Quiet areas in agglomerations – how our cities define them

forums
  • environment
date
23-10-2020

 

The global pandemic has brought the debate of noise to the masses and highlighted just how quiet our cities can be. With citizens noticing – perhaps for the first time – the difference fewer cars on our streets makes, and the mental benefits of natural sounds, now is the time to act and build on this awareness.

In rethinking our urban design in light of the COVID crisis, how can we improve the health and well-being of our citizens in relation to noise? How can we define and designate quiet areas?

According to draft national Italian guidelines, quiet areas in an agglomeration mean an area identified by the municipal authority in which Lden - or other appropriate acoustic parameter related to any source - does not exceed a defined limit value. ISPRA is developing criteria for quiet areas in agglomerations which could include that quiet areas are: defined by limit values in Lden less than or equal to 55 dB(A); accessible within 15-20 minutes walking; a territorial extension of at least 1000 square meters; integrated into a network of quiet areas within the agglomeration.

In agglomerations, existing and new quiet areas should be planned for in accordance with the intrinsic characteristics of the territory, providing a new “infrastructure”, based on existing green and blue networks. Ideally, according to Rosalba Silvaggio, we should work towards a network of connected quiet areas based on our cities’ green infrastructure. You can find out more in Rosalba’s presentation available below.

The pilot project QUADMAP (QUiet Areas Definition and Management in Action Plans) defines quiet areas as an urban area whose current or future use and function require a specific acoustic environment, which contributes to the well-being of the population. The city of Florence has seen reductions in noise and the implementation of relative quiet areas in school yards across the city as part of the project. The six schools in Florence were all heavily affected by traffic noise. Through a mix of measures – including wooden or nature-based noise barriers, the implementation of concrete blocks to absorb sound, road signs outside the school with speed limits, and internal sound-absorbing panels – the project saw a decrease in noise pollution by up to 9dB. Check out Arnaldo’s presentation available below.

  • QA definition: acoustic environment contributing to well-being of population

In Lisbon, quiet areas delimited by the municipality are exposed to a Lden value equal to or less than 55 dB (A) and Ln equal to or less than 45 dB (A) as a result of all sources of noise existing. The city has been working to go above and beyond the formal designation of quiet areas – which roughly cover an incredible 25% of the city – to increase the area exposed to low noise levels, explained Pedro Oliveira. Through a holistic approach, which takes advantage of green areas as low noise level zones, the belief is that this will be a guarantee of a new urban development for the inhabitants of urban centres.

  • QA definition:  Lden value equal to or less than 55 dB (A) and Ln equal to or less than 45 dB (A)

For Lisbon, ISPRAs recommendation to designate quiet areas according to existing or new green infrastructure is a reality. But what was the key driving force for Lisbon’s integrated planning for quiet and green areas? Political backing thanks to applying to (and winning!) the European Green Capital award. Learn more on integrating green and quiet areas in Lisbon in Pedro’s presentation available below.

Green infrastructure is a great place to start with defining a connected network of quiet areas, but we know finding space that is quiet enough to be designated as a quiet area can be difficult.

 

What are the main challenges to designating and protecting quiet areas?

We asked you, here’s what you said:

  • Definition of criteria for designation quiet areas
  • Protecting existing quiet areas
  • Densification in suburban and urban areas
  • Political will and political fear (of ability to keep an area quiet)
  • Existing and increasing traffic
  • Conflicts with land use (buildings, commercial etc)
  • Competing priorities – reducing noise at highest levels more urgent
  • Integrated design and engagement of green areas, as used also for sport, playground, music concert
  • Not considered during planning

Indeed, the main barrier appears to be first and foremost a lack of criteria to define quiet areas. While integrated planning, competing priorities and political will seem to be important confounding factors.

 

So how do our cities define quiet areas and what actions are they taking to reduce noise?

Out of the 25 city respondents, 14 of our members have designated quiet areas in their city. How doe they define quiet areas?

In the city of Barcelona, a number of actions are being undertaken to reduce noise pollution.  In one step, the city has defined different types of quiet areas:

  •  ZEPQA (Quiet areas specially protected): 50 dB(A) day, 40 dB(A) night. These are basically a few parks inside city.
  • ZUT (Urban quiet areas): These are new created zones, between ZEPQA and residential zones. 57 dB(A) Ld Le, 50dB(A) Ln. Includes very quiet residential zones and quiet parks in city.
  • Inner courtyards. 60 dB(A) Ld Le, 50dB(A) Ln. We have some public inner courtyards at the city centre where people can enjoy the calm out of the crowded streets.

Another step is the implementation of superblocks as a planning means of reducing noise pollution.  Within these superblocks, only residential cars are allowed, and a speed limit of 10 km/h is implemented. A preliminary pilot has show up to a 10dB reduction within these superblocks; Barcelona now plans to extend the pilot to other areas.

In Bergen, Pollution Control Regulations define quiet areas as a limited area suitable for recreational activity, where the noise level is below Lden 50 dB in urban areas and below Lden 40 dB outside built-up areas. Examples of quiet areas include parks, forests, and cemeteries. Such areas are often also shielded from visual noise, such as traffic, construction, advertising posters, etc.

In Espoo, quiet areas have an average sound level LAeq,7-22 is max. 50 dB, LAeq,22-7 max. 45 dB. In nature reserves, the guideline value for quiet areas is max. 45 dB LAeq,7-22 and max. 40 dB LAeq,22-7.

For Glasgow, quiet areas are defined  as areas which are a minimum of 9 hectares and in which at least 75% of the area is subject to noise levels not exceeding < 55 dB Lday.

For Milan, quiet areas are defined as Lden < 55 dB(A). Within the city, there are two kinds of quiet areas: 1. quiet areas within parks (actions: to provide the lower acoustic limits (noise zoonig plan)); 2. quiet areas within school gardens (actions: to provide 30 Zones in surrounding areas).

In Oslo, quiet area criteria are recreational value, as well as coverage (distance from populated area to nearest qua). The city has prioritized the most important parks in the city, as well as the areas around the waterways, which already are established as outdoor areas for recreational use.

Acoucite notes that the French environment code defines quiet areas “outdoor spaces that are remarkable for their low noise exposure, where the authority drawing up the plan wishes to control the evolution of this exposure in view of the human activities practiced or planned.” But other definitions include

  • The quiet zone is a place of resourcing where human beings, nature and biodiversity are in harmony.
  • A quiet zone contrasts with its external environment and its sound environment, associated with the other senses, is conducive to physical and mental rest.

Find out more about what our cities said in the below excel (available after login).

Please watch the recording here.