Though green space is known to benefit humans and municipalities, the competition for land in urban areas makes meeting the need for such space a challenge.
Even where minimum standards for green space such as parks, trails, sporting fields, bike paths, creeks and rivers, wetlands, and open space exist, the standards are often ignored, according to a report titled Green Around the Gills? The Challenge of Density for Urban Greenspace Planning in SEQ by Dr. Jason Byrne, associate professor Neil Sipe, both of Griffith University, and University of Queensland associate professor Glen Searle.
Rapidly growing urban environments such as South East Queensland battle sprawl development patterns with urban consolidation, the strategy of directing growth away from the urban fringe to infill projects. Green space standards are meant to ensure that infill development maintains adequate green space as the city grows.
The UK and US, for example, specify around two to four hectares per 1000 residents. In Australia, green space standards vary among cities and states, with some specifying that, for example, 10 per cent of a site’s developable area be green space. The generally accepted standard in SEQ is four to five hectares per 1000 residents, while in Brisbane it’s two to four hectares per 1000 residents.
However, the authors say, Brisbane has sometimes specified just one hectare per 1000 residents, and achieving even that may not be feasible, owing to high demand and high cost for land. The report cites a Brisbane City Council document that states flatly, “It is unlikely that sufficient land will be available to meet current standards of service for land for local public parks.”
Where standards are met, according to the report, urban consolidation becomes less affordable, as nearly double the amount of land would be needed. Thus, planners must choose how to balance the benefits of green space and the reduced affordability that accompanies it.
“This is an issue that planners in Brisbane – and elsewhere – have thus far avoided,” the report states.
One possible solution the authors offer is the “needs-based” approach. Rather than adopt a standard that applies to each green space, this approach attempts to consider the needs and wants of the likely users of each locale, now and in the future. Planners then design the green space for that population while maintaining as much versatility as possible.
Connection with the natural world provides well-known benefits to human beings. A study titled Public Greenspace and Life Satisfaction in Urban Australia by Christopher L. Ambrey and Christopher M. Fleming asserted three important points:
- Residents’ self-reported satisfaction with their lives is correlated to the percentage of public green space in their local area.
- Residents are willing to pay, on average, $1,168 annually for a one per cent (143 square metre) increase in public green space, indicating that proximity to green space can enhance property values.
- The value and importance of green space rises as population density rises, indicating that the most dense urban environments should contain green space.
The journal Psychological Science published research showing that health effects show a strong link to green space, as well.
Dr. Mathew White and his team of researchers at the University of Exeter Medical School in Truro, Cornwall, used national survey data that followed UK households over time. The data showed that respondents reported “less mental distress and higher life satisfaction when they were living in greener areas.”
"We've found that living in an urban area with relatively high levels of green space,” White said, “can have a significantly positive impact on well-being, roughly equal to a third of the impact of being married."
In addition, green space provides residents with better health outcomes by facilitating exercise and socialisation.
Green spaces also benefit municipalities by:
- Sequestering carbon
- Improving air quality
- Moderating heat islands
- Saving energy
- Moderating high winds
- Filtering water and allowing percolation
- Moderating erosion
- Increasing real estate values