State of the Environment 2011 Committee. Australia state of the environment 2011.
Independent report to the Australian Government Minister for Sustainability, Environment, Water, Population and Communities.
Canberra: DSEWPaC, 2011.
Heritage management processes are assessed by considering the governance systems in place that provide appropriate statutory responses, and adaptive management practices based on effective monitoring systems and adequate resources.
The overwhelming majority of heritage listing processes and impact assessments occur at the state or local level, often as a reactive response to threats. In many cases, the multilevel and cross-jurisdictional rules cause duplication and inconsistent (sometimes contradictory) outcomes. This is especially the case in jurisdictions where political intervention overrides heritage controls and values-based heritage decision-making. Particular current challenges arise from land zoning, building regulations and development standards that place major pressure on heritage places. Inappropriate zonings and regulations may lead to unrealistic expectations of development potential. Development standards can create a perception that every site should be developed to its maximum potential, irrespective of the effect on heritage items on the site or nearby. Local regulations and guidelines can be extremely influential in this regard because they represent the interface between the place, its owners or developers, and the authorities. These regulations and guidelines need to align with heritage values.
Unexpected adverse pressure on historic buildings has come from growing interest in sustainability and the green building agenda (Box 9.32). Balancing heritage conservation and sustainable development can be challenging, particularly in commercial contexts. Wasted embodied energy (i.e. the energy used to produce the building, including all materials) is an emerging issue. While a whole-of-lifecycle assessment would seem to be an obvious and appropriate approach, current standards and rules almost totally neglect embodied energy and focus on operational energy performance.
The sustainability agenda may also promote inappropriate changes that have adverse effects on individual heritage places if they are not sensitively handled. For example, prioritising native vegetation over exotic species can cause adverse outcomes for significant cultural plantings and gardens.
The green building agenda being embraced and promoted by many agencies is refocusing attention on responsible building and development, and directing resources to general upgrading of the built environment. This was thought to have benefits for heritage conservation, but instead the green building agenda is placing significant pressure on heritage buildings. The threats can be grouped into two categories—the impact of sustainability legislation, and the characteristics of heritage buildings themselves.
The Commonwealth Scientific and Industrial Research Organisation (CSIRO) has determined that the energy embodied in existing buildings in Australia is equivalent to 10 years of the total energy consumption of the entire nation.99 However, sustainability legislation measures only the operational efficiencies of buildings, with the aim of achieving immediate greenhouse gas savings by increasing efficiencies in heating, cooling and ventilation, saving water and minimising waste. Rating tools generally do not provide any recognition of the sustainability benefits of conserving existing buildings, and do not acknowledge the embodied energy inherent in these structures. They also do not consider the contribution that the inherent quality of materials makes to the lifecycle of a structure, nor the cultural value of the building to the community.
Wasted embodied energy is a growing issue, and a lifecycle assessment approach is appropriate. Better recognition could be paid to the potential for improvement of the environmental performance of existing buildings.100
The risk is that, rather than being conserved and refurbished, historic buildings will be demolished because they do not meet the contemporary green standards sought by industry and consumers. This risk will continue while the Green Star rating categories do not award points for heritage and do not adequately recognise the value in retaining existing materials. Points are awarded for replacing existing fabric with recycled material, even if the removed fabric is trucked off to landfill. Few, if any, points may be earned for retaining existing fabric; none for ensuring the 'integrity' of the original is maintained. Yet if the full lifecycle is considered, 'upgrading and maintaining an existing building to a 4.5 Green Star rating is 2.5 times more efficient than demolishing to build an equivalent 5 Green Star building measured at year 30 in the building cycle.'101 However, 'a refurbished building will not have new concrete poured and therefore cannot achieve the credit for use of recycled content in structural concrete.'102
The requirement for commercial building disclosure now ensures that the National Australian Built Environment Rating System (NABERS) energy ratings are available for large commercial buildings (soon to be extended to residential buildings). As the NABERS rating tool only rates energy efficiency, there is a great danger that heritage buildings will become even less desirable to owners and tenants who seek higher energy ratings. This pressure is already well demonstrated by government policies that require government business to be done from buildings with high NABERS ratings (e.g. the John Gorton Building that houses the Canberra offices of the Department of Sustainability, Environment, Water, Population and Communities).
The physical characteristics of a heritage building may also pose difficulties for achieving high energy ratings. Higher star ratings under the current rating tools require significant investment in innovative technologies, and significant additional plant area for capturing water, recycling greywater and installing cogeneration or trigeneration plans. Heritage buildings often have smaller floorplates, sit on smaller sites and may be constrained by the inability to excavate for additional plant area, or to add this to the roof area. These characteristics affect the ability of heritage structures to compete in the current rating system.
Several organisations are working to redress the imbalance of the current rating tools in a number of different spheres. Organisations include the Green Building Council of Australia, which is developing a rating tool for existing buildings; the Australian Tax Office, which is proposing a green investment tax incentive for retrofitting; and RMIT University and Heritage Victoria, which are researching the embodied energy of various heritage building typologies. The CSIRO is developing the Australian Life Cycle Inventory materials database for eventual incorporation into the Nationwide House Energy Rating Scheme, and organisations such as the Property Council of Australia run seminars on retrofitting existing buildings.101
The Cleland Bond is a historic warehouse in Sydney's Rocks district that has recently been adapted for commercial use, with a new lift, stairs, lighting and services, all of which improve energy efficiency and are clearly differentiated from the historic fabric. The adaptation makes use of the thermal properties and embodied energy of the existing structure (owned by Sydney Harbour Foreshore Authority, architect Tanner Architects; photo by Tyrone Branigan courtesy Tanner Architects).
Adaptive management is an important technique for effective heritage conservation. Developed for natural areas, adaptive management can be applied to both natural and cultural heritage places. It involves a continuous cycle of improvement based on setting goals and priorities, developing strategies, taking action and measuring results, then feeding the results of monitoring back into new goals, priorities, strategies and actions.103-104
One well-known adaptive management methodology is the conservation action planning approach of The Nature Conservancy. This process assesses context (values and threats) and outcomes (conservation status), then integrates this into development and implementation of conservation strategies that can be applied to any conservation site.104 Other approaches include the Australian Natural Heritage Charter processes, including the cycle of monitoring and review in preparing a conservation plan.59
Some Australian national parks already embrace adaptive management.105 Management systems in most national parks go some way towards this aim by identifying conservation needs and making well-informed decisions about management goals, resource allocation and impact assessment. However, formal monitoring and evaluation occurs in relatively few jurisdictions. Australia provides periodic reporting to UNESCO on its World Heritage properties (see Section 2.2.1) and both New South Wales and Victoria prepare reports on the state of their parks. Good systems are generally in place for assessing specific development-driven impacts on other off-park natural heritage places, but there are relatively few proactive and comprehensive conservation management programs.
Indigenous heritage places within reserved lands usually have management systems that identify conservation needs, involve traditional owners and make well-informed decisions about impact assessment and resource allocation. However, outside the reserved lands system, Indigenous heritage decisions are typically reactive and not always well informed, particularly development-driven impact assessment, which may occur without knowledge of the total resource. Little formal monitoring and evaluation or adaptive management of Indigenous heritage occurs.
Management systems at all levels of government generally facilitate well-informed decisions about resource allocation and impact assessment for historic heritage. There are some excellent examples of innovative, values-based decisions leading to good outcomes (Box 9.33). However, formal monitoring and evaluation rarely occurs. Management systems for listed historic places in public ownership identify conservation needs and generally adopt the methodology advocated in Kerr106 and the Burra Charter,46 an approach that includes setting goals, determining priorities, developing strategies and taking action, but places less emphasis on feeding the results of evaluation and monitoring back into management. For privately owned, listed historic places, the systems for impact assessment and resource allocation vary greatly across jurisdictions, owners and site types.
The Lake Margaret Power Station on the west coast of Tasmania is one of the state's earliest hydro power stations. In 2006, the upper station was decommissioned and a proposal was lodged to demolish the unusual 2.2-kilometre woodstave pipeline that fed water to the station. The 70-year-old King Billy pipeline had reached the end of its effective life, and demolition was the only pragmatic option. However, the high heritage value of the site was a major consideration for future options. A collaborative approach between Hydro Tasmania, the Tasmanian Heritage Council, local government and community representatives ensured the preservation of the heritage values of the area. Hydro Tasmania's engineers found an economical solution to reconstruct the pipeline using ash cedar. The project blended modern and traditional construction techniques and incorporated elements of the original works dating from 1914. Three sections of the original King Billy pine woodstave pipeline have been preserved onsite and a further three were donated to museums. The power station recommenced operations in October 2009.
Section of the woodstave pipeline, Lake Margaret Power Station, Tasmania (photo by David Scott, Heritage Tasmania)
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