Dave Cherry discusses how Leeds intends to climate proof its services.
Even if all greenhouse gas emissions ceased immediately, the world would still be destined for significant levels of unavoidable climate change; indeed predictions show a global surface temperature rise of between three and four degrees Celsius by 2080.
In the face of this, and mindful of the cost of inaction, Leeds City Council (LCC) has devised a scheme to climate proof its estate, its service provision and council strategies.
The initial task was to raise awareness with an investigation of local weather records. This identified some noticeable early trends, or signals in average weather, all of which are consistent with projected climate change.
For example:
- seasonal warming, greatest for autumn and winter;
- increasing frequency of wet months (more than 165% mean monthly rainfall), no change for dry months;
- tendency for more intense, short-period, rainfall events;
- decreasing frequency of air frost and snowfall; and
- increasing frequency of winter gales.
Although this information is not scientifically robust, it has been extremely useful in raising awareness to any doubting Leeds officers and councillors, that our local climate really does appear to be changing and that climate change is something real and tangible that affects us all.
These trends have provided a catalyst to further investigate how climate change may affect Leeds' services, both in terms of weather related impacts and also to enhance any opportunities.
A local climate impacts profile
It was decided prudent to investigate whether Leeds is already vulnerable to existing climate risks and create a local climate impacts profile (LCLIP).
This was based on archive media headlines reporting on severe weather related events, reported by the Yorkshire Post and the Yorkshire Evening Post. Initial findings for between 2002 and 2008 identified over 150 weather-related news stories within the Leeds region.
Each severe weather event was assessed for "magnitude of impact", in terms of damage, disruption and health effects. Flooding and wind damage were identified as the most prevalent climate risks for the area both in terms of frequency and severity of events. It is worth noting that spring and autumn heralded few significant weather events.
The consequences for each high-magnitude severe weather event were looked at, both in terms of direct and indirect implications on cost and service delivery. The profile also looked at how LCC has thus far responded to these weather hazards, in terms of event trigger levels, monitoring of events and how it intends to ‘Build Adaptive Capacity' and develop effective climate-proofing measures to reduce future vulnerability to climate change.
The next step to was to seek advice from the LCLIP on existing climate risks and vulnerablities for Leeds. In addition, the new UK Climate Projections 2009 can project the probability of a specific threshold event being exceeded, for future decades.
This information was then incorporated into a risk assessment methodology to develop the most cost-effective climate proofing measures, including the level of protection required over a given length of time.
This process is also aimed at helping to identify and enhance potential opportunities likely to arise from climate change.
Sometimes climate proofing turned out to be a matter of common sense rather than rocket science. For example, local flooding problems can be caused by blocked drains and watercourses, which can be dealt with by improved cleaning.
However, many other sources of flooding may be caused by building on floodplains, rapid runoff, or simply inadequate drainage capacity.
It is this sort of scenario where detailed risk assessment and the bespoke design of climate proofing will pay most dividends such as including flood alleviation measures, sustainable drainage systems and amendments to planning conditions in the first place.
Emergency planning
Finally, to back-up these proactive measures, it is essential to provide an effective and coordinated reactive response in terms of emergency planning and deployment of severe weather plans.
To this end the strategic adaptation working group has worked with the Council's Emergency Planning and Risk Management Units to develop its own risk assessment methodology and create a community risk register for Leeds.
The register highlights an annual high-risk ratio for specific severe weather events, including flooding, wind damage and short-term snow disruption.
This work has also contributed towards the development of local severe weather plans, which establish efficient reactive measures for dealing with the impacts of local severe weather events.
Vulnerability mapping
But the ultimate aspiration for the Leeds climate proofing strategy would have to be the development of a GIS-based vulnerability mapping system for existing and proposed climate risks. This would attempt to identify the location of vulnerability hotspots for specific weather events, which in some locations may not have occurred before.
For example, the Council and the Environment Agency are currently developing Arup's flood visualisation model for Leeds. This model is capable of mapping river and flood heights and the extent of flooding across Leeds.
So it will add to both reactive and proactive measures to combat flooding, thereby assisting emergency and land-use plans and policies.
Vulnerability to wind damage is also currently being investigated, as Leeds experiences frequent high winds, exacerbated by turbulent flow and funnelling caused by local topography and effects of tall buildings.
A new methodology for sustainability appraisals has also been developed that follows The Natural Step process, developed by Forum for the Future.
The sustainability appraisals will have a separate climate proofing template that contains relevant questions bespoke to the plan or development being assessed. The intention is to focus the minds of planners and developers on future climate risks which relate to warmer wetter winters, hotter drier summers, flooding and gales.
The end result of these deliberations is the Climate Change Strategy for Leeds. Launched last summer, it incorporates all the elements discussed and highlights how climate proofing should be given equal importance to measures to reduce greenhouse gases in the first place.
Examples of recent climate proofing successes include:
- Identification of the top 50 "flood hotspots" involving small watercourses/culverts and implementation of fortnightly cleansing, backed up with photographic evidence;
- the widespread use of sustainable urban drainage systems (SUDS) during construction of the East Leeds link road. Measures included raised carriageway, granular drains, underground storage equivalent to one cubic metre of water/metre of carriageway and balancing ponds, which ensure run-off rates are reduced following construction; and
- bespoke fitting of flood boards and air brick covers and coordinated flood warnings to vulnerable dwellings, as an interim measure, whilst longer-term measures are being planned to reduce flood risk from the local watercourse.
Future priorities will involve climate proofing the most vulnerable elements of transport/utilities, health and social care, the natural environment and the built environment.
In addition Leeds is to ensure compliance with the National Indicator 188 (Planning to Adapt to Climate Change) and this will involve further partnerships working across the Leeds district to implement relevant procedures to identify existing and future climate risks and develop cost effective climate proofing.
Finally, Leeds has received Regional Improvement and Efficiency Programme funding to help champion the West Yorkshire Adaptation Action Plan.
Summary of Adaptation Policy
- Use of climate fluctuations and LCLIP findings to raise awareness of climate change and the urgent need to climate proof all LCC services.
- Use of risk assessment methodologies to identify climate risk threats and opportunities for utilities, built environment, transport, health and social care, and the natural environment.
- Use of UKCIP climate projections to help identify when, where and to what level cost-effective adaptation measures should be developed.
- Consider reactive emergency measures and proactive climate proofing for existing and new build.
- Incorporate sustainability appraisal climate proofing for land-use and transport planning developments.
- Implement our adaptation strategy and monitor its effectiveness.
