Professor Robin Coningham and Dr Christopher Davis from our Department of Archaeology explain why sustainable access to water is so important and how Durham is helping.
Durham’s UNESCO Chair team is working with partners across the University, and internationally, to develop a new programme exploring how historic hydraulic infrastructure within the Kathmandu Valley can be revitalised for sustainable water supplies, but also to embed resilience within these systems in the face of disasters caused by seismic events, rapid urbanisation and climate change.
The UN estimate that by 2030, with current climate projections, there will be around 560 disasters a year globally. Disproportionately affecting regions with high levels of poverty, disasters can exacerbate existing inequalities and place more people at risk from their devastating effects. While international donor agencies have favoured solutions that invest in mega-infrastructure and can often be imposed on communities, it has been identified that more localised solutions, informed through traditional knowledge integrated with scientific analyses, can provide more sustainable results.
This was identified previously in Nepal’s Kathmandu Valley, where recent Durham-led fieldwork highlighted the critical role of multidisciplinary teams working alongside communities to integrate traditional and indigenous knowledge from historic infrastructure for developing future resilience in the face of natural disasters and the effects of climate change.
An area of particular concern relating to climate in Nepal and across South Asia, partly linked to the unpredictability of the annual monsoon, is access to sustainable sources of clean water.
Archaeologists have studied past hydraulic systems in detail to analyse the origins, development and declines of past societies, but are becoming increasingly aware that understanding these ancient systems can provide knowledge for indigenous adaptations, innovations, as well as ready-made environmentally adapted infrastructure, to tackle challenges faced in managing and sustaining water supplies for the future.
The Kathmandu Valley contains one of the fastest growing urban populations in the world and has seen a 1362.5 per cent increase in population since the 1950s to today, with some 1,521,000 people inhabiting its metropolitan areas. Placing more people at risk from natural disasters, including seismic events, as exemplified by the 2015 Gorkha Earthquake, population increases have strained essential infrastructure and exacerbated resource shortages, including water supply.
Equitable access to safe and affordable drinking water is a core UN Sustainable Development Goal (UN SDG 6). Water is not only a key resource for human health and prosperity, but water insecurity can also be negative for economic growth and can lead to potential conflict linked to unequal access and rights.
Poor infrastructure, damaged and strained by unchecked development and climate change, has created an unsustainable water supply within the Kathmandu Valley. It is estimated that 20 per cent of households have no access to domestic water sources and that two thirds of all households lack easy access to safe and adequate water supplies. With demand outstripping supply, solutions, including the use of groundwater pumps and tanking water into the Valley from outside, are not long-term answers to this chronic issue.
The Kathmandu Valley has a unique irrigation infrastructure of rajkulos (royal canals) which feed into a network of hiti (sunken brick-lined tanks with stone spouts). Many of these systems are not just vestiges of the past but continue dynamic roles in the present and are foci for communities and their intangible traditions. While many are still in use, a multitude have become dry from blockages and damage caused by unchecked development. The rehabilitation of aspects of this ancient hydraulic infrastructure could substantially contribute a low-cost solution to the Valley’s acute and worsening water supply issues.
As part of a newly-secured research grant, a Durham-led team will integrate ‘scientific’ analyses of rajkulos and hiti with historical sources and community knowledge systems to identify how this hydraulic infrastructure is adapted to the Kathmandu Valley’s geography and climate. They will also examine the inbuilt mitigations of this hydraulic infrastructure in the face of disasters, from earthquakes and landslides to flash floods, the latter of which are increasing in frequency due to the intensity of monsoon rains and run off from melting glaciers.
This integration of ‘scientific’ and traditional knowledge systems will evaluate the potential of revitalising historic hydraulic infrastructure for sustainable water supplies, to provide sustainable and resilient systems to counter the continued risks and crises facing communities from increased population, rapid urbanisation and climate change.
One of Patan’s many brick-lined tanks (hiti), providing water to communities of the Kathmandu Valley, as well as forming foci of intangible traditions
A historic water canal (rajkulo) within the Kathmandu Valley flowing from the headwaters of the river Lele through recent urban development on its way to the medieval city of Patan