The Carbon Landscape

The Carbon landscape 

“As a profession we are responsible for creating large volumes of carbon dioxide though our design work bit it could be argued that through planting we also trap carbon. The question is: Does our carbon consumption offset our carbon creation? “

Uncomfortable assumptions

Landscape Architecture is recognised as a design disciple that focuses on the enhancement and protecting of land, natural resources, visual landscape amenities and creating meaningful community spaces. The core values of our education and the tools of our trade are plants and ecological system. With this type of rap sheet it is not hard to focus on the environmental good that landscape architects do, but are Landscape architects being lulled into a faults sense of environmental confidence due to the generally green looking nature of the final produce?

Are we considering the entire environmental baseline in our work even the less visible and tactile such as carbon dioxide and other forms of pollution associated with the cost of design, materials and management systems that we specify. 
As the issues of global warming has become more widely accepted as a real scientifically creditable and the role carbon dioxide plays within the process, the parameters of sustainability are becoming more focused on embodied energy and carbon dioxide and other greenhouse gases.   So what would happen if landscape architects included the carbon cost of their work as part of the final outcome of a project, would the project still be considered having a positive environmental impact, could it confidently labelled as sustainable?

The carbon footprint of a landscape architect

I have spent six years working on projects in the United States of American, India and New Zealand all of which would at face value be considered sustainable; they incorporated a sensitive approach to water, ecological communities and materials were carefully selected. On the face value of the projects look environmentally friendly but I felt uncomfortable with this assumption. I want to see how they would stack up if I added the carbon dioxide cost.

To test the idea I reviewed the last fourteen years of landscape projects I had personally been responsible for. There was not one tool in which I could use work out the total carbon cost of my work and had to rely on web carbon calculators for office and travel, European and American carbon research on materials which gave me an approximate carbon cost of my work. The initial carbon value was high and a little concerning. I had a hope that the large reforestations projects that I had worked on in India and New Zealand would offset this high carbon cost of my work.  I then set about using English and Canadian research on carbon sequestering by trees to see if the reforestation would offset my initial carbon value making my landscape design career “carbon neutral”.

The outcome was a little concerning. I was approximately 120, 000 trees short of being carbon neutral. The calculation could easy be called course and crude of which it is. I could argue that there are other plants types and ecological communities that I specify or created that also consumption carbon dioxide helping to offset my carbon total. On the other hand I only calculated out a portion of my carbon cost, due to the lack of carbon information I did not include the carbon cost of implementing the projects or the ongoing carbon cost of maintaining of which both carbon values would have been considerable.  Over the course of my career my work has not focused on material heavy urban design and the last half of my career has focused on being sensitive to the carbon cost of my work so in general I believe my carbon footprint is no bigger than that of the average landscape architect. 

For me this process of calculating out carbon highlighted several important conclusions:

  • There is a fundamental imbalance in our work; the planting we create cannot possibility off set the high embodied energy cost of the materials we most commonly rely on as landscape architects.
  • What became clear from calculating my carbon footprint is that the high carbon values don’t sit in the areas that we traditional try to control such as focusing on creating sustainable and carbon friendly office and transportation. The carbon footprint of my office and travel was manageable and possible to completely offset.
  • The highest carbon values sits in the carbon cost of the materials we use and the ongoing maintenance of landscapes.
  • If it is assumed that urban landscapes are material intensive and produce a high carbon footprint which is impossible to offset within the same land area then the long life expectance of that urban space becomes critical making the urban renewal  come at a high carbon cost.
  • My professional carbon foot print is probably average for this industry which brings into question the assumption of the profile landscape architecture being a disciple that protects the environment.

If the specified more carbon within our work is greater than our planting can possibly offset putting us on the wrong side of the carbon debt. If we can accept this uncomfortable conclusion then the questions has to be what we do about it.

The four stages of the carbon cycle within the landscape.

To help understand how carbon is integrated into the design process it helps to break this carbon value into four distinctive stages in which a landscape architect can influence and potentially reduce the associated carbon. The first three stages in the carbon life cycle are reasonably obvious; design, implementation and maintenance.
The fourth stage “urban renewal” is not so obvious and yet potentially has the highest carbon value associated with it. The “lifespan” of a landscape design before it gets removed and the space re invented with the associated carbon.
Each carbon stage has differing degrees of importance. With good management a landscape firm might for example save 300 tons of carbon per year with good office transportation and energy policies, but a single design decision, poor material choice or poor landscape management or maintenance policy could cost 1000 - 10,000 tons of carbon to a project, effectively nullifying any carbon savings from the office.
 
Carbon Neutral Design Firms

Each design firm has a carbon footprint which can be managed to be minimal, or even neutral (zero carbon cost). A local carbon conscious firm working on a local design would add few carbon points to a landscape design.

Carbon within the design process

Design program
All designs start off as a series of assumptions facilities to be offered on the site, locations of buildings, circulation and surfaces often decided by the designers (design program). These assumptions should always be tested with the surrounding community keeping in mind how a community or demographics may change over time and whether the design program is flexible enough to deal with these potential changes.
  • If the testing of the design/planning program is not rigorous there is two possible negative out comes; The space is not appropriately programmed and does not last the test of time, requiring removal or renewal with the associate carbon cost. 
  • The project may have over specified the facilities, hard surfaces, paths required beyond communities’ real requirements; hence the project consumed more CO2 to build than necessary.  
 
Material selection

How a space is designed and the amount and types of materials specified by the designer comes with a carbon cost. The carbon cost of materials is measure in subcategories depending on issues such as how the raw product is harvested, to how far the final product has to travel to the final location.
The basic rules would be use the minimal amount of metals and concrete on a project to meet your design needs. Use materials from the actual site were possible, locally sourced materials being the next best option. If you have are required to use materials with high carbon values do it in a way that maximizes that materials qualities (durability, function) with it minimal consumption on the project.

The implementation of the Landscape

Most landscape architects would understand that there is a carbon cost in the construction of a project; it is one of the more tangible of the carbon stages. If it is a goal to minimize the amount of carbon (and waste generated) within the implementation phase of a project you have to consider the options for building and planting
 
Management of landscape
Landscapes are dynamic living places that require resources such as water, chemicals, labour and fossil fuels to maintain the landscape in the desired condition. If a landscape is managed over decades then it is possible for the carbon and resource costs of maintaining that landscape to easily outweigh any of the resource and carbon savings gained in the design and implementation stages. The environmental cost of a landscape management and all opportunities utilized to minimize those costs.
 
Urban Renewal

If you assume that it is presently not possible for landscape architects to create carbon neutral urban designs and that it is likely that most urban landscapes are going to cost the community and environment thousands if not tens of thousands of tons of carbon to design and implement; The carbon friendly approach to take is to design in a way that ensures that urban space has a life span measured in half centuries rather than decades. Unfortunately this generally does not seem to be the case, urban spaces including award winning design tend to here a shelve life of 20-30 years before the space gets a new design and “revitalized” cycling back though the high carbon process of design and implementation.

Carbon Future

Carbon” needs to be one of these baselines measures added to our landscape checklist along with water, materials, energy, bio diversity, community, economics and sustainability.
The carbon costs of our projects needs to be added to the design equation ...and  the carbon figures minimized and offset
and what community and environment paid the cost for the production of the materials used, were the waste goes after implementation, the cost of the fuel and chemicals it takes to maintain the landscape
 
  • It is possible to work out the carbon cost of a project; as landscape architects we should be working out this cost, and offsetting it as much as possible within the design, implementation and management of a project.
  • Create enduring landscapes that stay in its static form for a long period of time making the most of the initial high carbon cost of creating the space. This involves designing and building public urban spaces that will withstand the test of time, aesthetic and public scrutiny.
  • Create low embodies landscape maintenance
  • As an industry we need to research new materials, manufacturing techniques, and construction practices to come up with a palette of options that have the lowest possible embodied energy factors, waste production and environmental impact.
  • We need to develop the skills to calculate the carbon cost of a landscape design and management plan. 
  • Landscape members and the landscape Institute should consider becoming carbon neutral.
  • It is important that as landscape architects we work hard to avoid the pitfalls of poor site design, materials selections or a heavily focused on a style, trend or design fashion that leads down the path of short lived designs.
  • Landscape architects should be aiming at creating landscapes with longevity that will survive changing demographics, community growth, charges in fashion and physical weathering. We need to create landscapes that are flexible enough to deal with charge.
  • Some design no longer performs on a physical level, the pavers were not durable or reflected too much light, were hard to clean. The spatial layout did not create safe spaces for the community to occupy, the circulation did not predict the way the community would move thought the spaces.
Published:
Topos 61, 2007
IFLA new letter 2008
"Der C02-FuBadruck der Landschafts architetur", Garten+Landscyhaft, January 2008

Author:
Craig Pocock

Date:
2007-2008