Heritage Impact Assessment (HIA) has recently emerged as a conflict-solving tool to improve World Heritage (WH) conservation in line with sustainable development policies. The increasing number of requested HIAs for affected WH properties over the last years reveals that more attention is being paid to HIA as a practical tool to adequately support the protection and management of historic monuments and sites against new constructions and development. However, the application of integrated and systematic impact assessment methods within HIA still remains a key challenge in different HIA projects. Therefore, this paper contributes to the further development of a transparent and systematic procedure of HIA in accordance with Environmental Impact Assessment (EIA). It also explores different standard methods of impact assessment in EIA and discusses their applicability to cultural World Heritage properties. Finally, the paper emphasizes a need for developing integrated impact assessment methods to address the multiple impacts of development projects. Such methodological enhancement can further contribute to mitigation strategies and decision-making to protect World Heritage properties within the context of sustainable development.

Despite various opportunities, urban development projects have been causing significant challenges to the preservation and conservation of historic cultural heritage. In particular, an increasing number of World Heritage (WH) properties are impacted by the direct and indirect effects of development projects, reflecting the existing uprising conflict. Grasping the challenge, Heritage Impact Assessment (HIA) has been developed as a proactive assessment tool to identify and predict potential impacts, mitigate the negative impacts on heritage values, and sustain the attributes conveying OUVs in WH assets. The growing demand for urban development and its potential impacts on cultural heritage properties underscores the necessity for the development of a targeted Heritage Impact Assessment methodology for urban development threats. To adequately address multiple impacts, this paper proposes a triangulation of a qualitative matrix for impact identification and a semi-quantitative indicator-based index for impact analysis and evaluation. The methodology is applied to the World Heritage property of Masjed-e Jame of Isfahan in Iran. In drawing upon this example, a systematic and integrated impact assessment procedure is developed to capture a broad category of potential impacts and their significance that is crucial for determining site-specific mitigation strategies and informed decision-making within the context of heritage management and sustainable urban development.

In recent years, many “living” cultural and urban landscapes on a large scale were inscribed on the World Heritage List. However, such complex World Heritage properties generate frequently challenges concerning their management due to transformations caused by to pressure to change. As a result, there is a need for new proactive systematic approaches to assess such transformations combining innovative technical solutions with a systematic approach to using attributes and values conveying their Outstanding Universal Value. Taking the World Heritage cultural landscape Upper Middle Rhine Valley as a case study, this paper investigates such a systematic instrument to monitor transformations and to assess their impact on the OUV and integrity of UNESCO World Heritage properties. It is concluded that such systematic technical instruments can be helpful to support strategies for an integrated management combining preservation and sustainable development. However, an in-depth theoretical knowledge of sites’ OUVs and attributes and values related thereby, as well as a sound integration in existing legislative frameworks and the participation of stakeholders on various levels is indispensable to guarantee their full effectiveness.

This case study sheds light on potential ways of embedding water-related heritage in an integrated strategy of sustainable urban development in Bergen, Norway. Particular attention is paid to the ongoing Heritage Impact Assessment (HIA) process in Bergen, which was started in 2019 to assess potential impacts of Bergen’s new transport strategy on the World Heritage site. Various HIA reports have been compiled and discussed with Bergen’s planning authorities, other experts and in a public hearing process. The municipality of Bergen has used the HIA to reconcile the preservation of the Bryggen World Heritage site and its historic harbor setting with its strategy for sustainable urban development. Hence, the HIA is serving as an essential tool to implement the UN Agenda 2030 for sustainable development.