Causes of Collapse

While removing the rubble at the Kasthamandap, we identified that the heavy machinery used in the rescue had ripped through floor levels and foundations that had survived the earthquake.

We also found that the monument’s brick foundations were set in a mud mortar, which had offered flexibility during shocks and that, as a result, earthquakes had not cracked or damaged their two metre deep walls.

Our excavations revealed that this was a major contributing factor in the Kasthamandap’s collapse, because key structural elements were left freestanding and the critical link with the resilient and undamaged foundations lost.

Before our post-disaster excavations, the Kasthamandap had only been documented through its standing remains and local traditions. Traditionally, its construction had been placed in the twelfth century CE. Furthermore, the installation of Gorakṣanātha shrine, was dated to around 1379 CE.

When the scientific dates for the Kasthamandap’s foundations came back from the laboratory in Stirling, they indicated that it was constructed at some point between the early seventh and early ninth centuries CE, several hundred years earlier than previously thought. This demonstrated that they had not only proved their resilience to the 2015 Earthquake but had survived centuries of earlier seismic shocks.

Dating of timbers also found that there had been a major reconstruction or renovation at the Kasthamandap, at some point between the eleventh and twelfth centuries CE. This illustrates how monuments were built and redeveloped over time, and this reconfiguration of the monument may be where the traditional construction date originates.

The scientific dating of timbers also identified that a lion-headed capital from the monument dated to between the fifth and sixth centuries CE. Earlier than the Kasthamandap's construction, this capital was potentially an original element of an earlier version of the monument, for which we have no archaeological physical evidence; it may have been reused from an earlier monument located within the vicinity of the Kasthamandap; or, it was re-carved from a larger earlier timber from an earlier version of the Kasthamandap or nearby monument.

Such early activity should not be surprising as settlement in Kathmandu is well known from Licchavi period inscriptions, which date to between the fifth and eighth centuries CE. Furthermore, geoarchaeology identified human activity in the region of the Kasthamandap from around 1050 BCE and mapped the Kathmandu Valley’s environmental changes as it transformed from a rural landscape through to a cityscape.

Sanskrit textual traditions record the deposition of different soil mixtures within different cells during the construction of monuments and our analyses has begun to identify their chemical composition, scientifically linking intangible practice to physical remains

Designed with structural resilience, the Kasthamandap’s plan was also created as a sacred representation of the Universe, or mandala. Cross-walls within the foundations created a nine-celled pattern - with a further, nine-celled mandala located within the central cell below the Gorakhnath shrine.

Carefully recording each of the personal effects recovered from the debris of its collapse, we also encountered artefacts from the Kasthamandap’s foundation. Circular gold foil discs, with mandala designs, were found within each of the four saddlestones that had supported the superstructure. The discs were ritual deposits at each of the four corners of the monument for the prosperity and welfare of the building.

The use of Ground Penetrating Radar also allowed us to look beneath the brick pavements surrounding monuments, such as the Kasthamandap, to identify if there were earlier structures hidden below. Surveying the squares where the collapsed monuments were located, radar signals identified earlier monuments across these historic sites as well as the location of modern pipelines.

This has allowed for the development of Archaeological Risk Maps, which can guide development and repairs within protected heritage zones.

The most spectacular results were within Bhaktapur Durbar Square, where GPR surveys and excavations uncovered the foundations of the Lam Pati, a building that collapsed during the 1934 Bihar Earthquake, were found sealed below successive levels of paving.

GPR survey and targeted excavations have also identified previously unknown subsurface heritage within Patan and Hanuman Dhoka Durbar Squares, as well as within the courtyard of Changu Narayan Temple.

The Heritage of South Asia faces an increasing number of threats, ranging from natural disasters, such as earthquakes, to the impacts of accelerated development and conflict. It has also become increasingly apparent that the promotion and development of heritage sites can offer social and economic benefits for stakeholders and local communities. Although complex, the delivery of such benefits is challenged by a general lack of co-ordination between local stakeholders, researchers, heritage managers and local government administrators in the promotion and protection of heritage sites within development programmes.

Reiterating existing the Department of Archaeology (Government of Nepal)’s Conservation Guidelines for Post 2015 Earthquake Rehabilitation, it is hoped that these resolutions will combat the many challenges facing heritage sites in Nepal, and throughout South Asia, leading to its enhanced protection.

To raise awareness of these threats and challenges, we held an international workshop ‘Heritage at Risk 2017: Pathways to the Protection and Rehabilitation of Cultural Heritage in South Asia’ in Kathmandu in September 2017, funded by the Arts and Humanities Research Council (UK)’s Global Challenges Research Fund, and coordinated by Durham University’s UNESCO Chair in Archaeological Ethics and Practice in Cultural Heritage, the Department of Archaeology (Government of Nepal), ICOMOS (Nepal) and UNESCO’s Kathmandu Office.

Resolutions included the evaluation of foundations of damaged and collapsed heritage sites through multi-disciplinary investigations. While investigating the issue of seismic stability, the workshop’s participants suggested that the foundations of monuments should be retained as far as possible if undamaged. As well as urging archaeological investigations before subsurface interventions at historic sites, the resolutions called for the development of a network of South Asian experts and key disaster responders to be rapidly mobilised to protect and rehabilitate sites and monuments following natural and cultural disasters as well as conflict.

Our team are continuing to examine the artefacts and samples from the Kasthamandap, discovering new insights into the monument’s history - insights which could have been lost if rapid reconstruction had taken place. Our archaeological work has shown how vulnerable the monuments of Kathmandu are from earthquakes, but also the equally great risk from the response to such disasters.

While humanitarian efforts are of paramount importance, heritage protection and the recovery of historic material are also critical in the aftermath of a disaster. To develop this capacity, the team ran a live exercise at a collapsed monument in a safe environment.

Fieldwork in Kathmandu has demonstrated that rescue archaeology can uncover the previously unknown stories of iconic monuments and that we can provide critical information as to why monuments collapsed. It has also demonstrated that archaeologists can play a key role in training first responders to protect heritage in the immediate aftermath of an earthquake, thus ensuring that valuable historical evidence is not further destroyed.

This provided an ideal opportunity for first-responders, including site managers, emergency services and the army, to develop skills and knowledge of the careful removal of rubble and artefacts without specialist tools, whilst prioritising the recovery of human life. We also trained them to recycle historic materials, as the earlier post-disaster emergency response resulted in the dumping of millions of dollars' worth of reusable historic bricks.

At a time when heritage sites across the world are at risk from natural disaster and conflict, we hope that the approaches and methodologies pioneered in Kathmandu can be successfully transferred elsewhere.

Our excavations have shed new light on the early rituals associated with the construction of monuments in the Kathmandu Valley and have demonstrated that the Kasthamandap and other historic structures had strong foundations, undamaged by centuries of earthquakes.

The continuation of festivals, rituals and everyday life in and around these monuments in the aftermath of the earthquake also demonstrates the resilience of its local communities.

When digging at the site, it also became immediately apparent that, although in ruins, the Kasthamandap still remained a focus of daily activity and ritual in Kathmandu.

The footprint of the monument still hosts a market, with marigold garlands, as well as fruit and vegetables for sale. Ritual also continues, with ceremonies continuing on the levelled brick, and festivals and processions following traditional routeways of movement around the monument and city.

These economic and ritual activities again highlight the intangible value of the Kasthamandap to its communities, even after its collapse, and the continued importance of this monument and its place in the daily rhythms of the city and in the vibrant social dynamics of Kathmandu today.

Our research results have been used by the Kasthamandap Reconstruction Committee to establish the best ways to repair the monument. This has highlighted the value of traditional and indigenous construction techniques and skilled craftspeople and artisans for seismic safety and integrity. This includes the use of mud mortar within foundations and the installations of copper plates to reduce risks from damp and rot, as well as to deter insect damage. Uncovering previously ‘lost’ or neglected vernacular traditions and indigenous knowledge has directly addressed significant concerns expressed by the International Council on Monuments and Sites (ICOMOS) that authenticity in Kathmandu is unnecessarily being destroyed, and intangible value disrupted by the ways in which restoration work and international disaster relief efforts were being implemented.

While the programme of rescue excavations has uncovered a deep and previously unknown past, the Kasthamandap continues to be relevant to diverse communities in the present. The reconstruction has not only rebuilt a monument and filled a gap in the skyline, it has also strengthened the bonds between communities and the Kasthmandap through intangible traditions and rituals.

The Kasthamandap is an example of how interdisciplinary study and community engagement can lead to successful and meaningful authentic rehabilitation of Kathmandu’s historic monuments.

While there are many lessons learned for decision makers, practitioners, academics, crafts people and residents, there are a number of broader lessons learned, which are relevant for the Kathmandu Valley and beyond.  Some of these were developed within the UK National Commission for UNESCO’s Policy and Practice Brief on ‘Heritage, Disaster Response and Resilience’ with Praxis and AHRC.

From this, the key insights were:

ONE. Heritage – cultural and natural, tangible and intangible – is an invaluable resource for emergency preparedness and recovery.

TWO. The effectiveness of disaster resilience and recovery depends heavily on the implementation of inclusive, locally and culturally appropriate approaches.

These lessons learnt from post-disaster fieldwork in the Kathmandu Valley are also relevant to other pressing global challenges.

This was discussed during the recent International Co-Sponsored Meeting on Culture, Heritage and Climate Change (ICSM CHC), sponsored by the IPCC, UNESCO, and ICOMOS, where the integration of ‘scientific’ and indigenous knowledge systems are helping our understandings of past and future adaptations for the protection and preservation of cultural heritage and their communities in the face of climate change. 

“The Kasthamandap has proved the importance of archaeological and scientific studies, especially for those cases where history and culture are embedded below the surface

This helped to scientifically resolve the ever existing debate about the date of construction of the Kasthamandap and the history of the Kasthamandap was pushed further back in time.

Furthermore the investigation also indicated the probable reasons behind the collapse of the Kasthamandap. It was clear that the lack of timely maintenance as well as improper interventions in the past was instrumental in the collapse of the Kasthamandap.

The Kasthamandap is but a tip of the iceberg. There are numerous monuments and sites in Nepal awaiting for proper archaeological studies that could uncover great information about their past.

In absence of strong heritage policy in Nepal, the heritage structures are continuously being encroached erroneously"

Mr Rajesh Shakya MP