Our Heritage in an Era of Climate Change

The tremendous downpour of rain in mid-June came as a surprise. It closed roads, disrupted rail travel and led to the issue of 4,000 sandbags across Flintshire alone. A fortnight later I visited my daughter in the south of England and experienced pretty unbearable heat of the hottest day of the year so far. Crazy weather? You can say that again! There are some important implications for aspects of Our Heritage in what is clearly an era of climate change.

The first point is undoubtedly the risk posed to our valued Scheduled Ancient Monument of the Packhorse Bridge which spans the River Alyn between Hope and Caergwrle. The story of the Bridge has been well documented in previous articles. It was constructed in the third quarter of the seventeenth century as part of the on-going improvement in communications which foreshadowed the era historians have dubbed the ‘Industrial Revolution’. 

In the November 2000 it was virtually destroyed when the arches became blocked and it crumbled under the weight of a tremendous amount of floodwater. The damage done exposed a cast iron active sewer pipe, which is embedded in the footpath. Fortunately this was not damaged by falling masonry and the River Alyn was spared the impact of the prospect of a local environmental disaster of a sewage spillage. The blocked arches had caused the flood water to back up causing flooding in the homes of adjacent properties in Sarn Lane. Their relief from this misery only came when the Bridge itself gave way and released a huge amount of water into the downstream section of the river. The Bridge was subsequently restored at a cost of £100,000 by Welsh Government and Flintshire County Council.

Experts from Natural Resources Wales  (NRW) provided every assurance that, on the basis of their modelling an episode like that of 2000 could not happen again for another 70-90 years. The pressure was off, it seemed. There was no urgency for anyone to respond to local lobbying about the need for action. However, this June we came very close to a similar experience as the arches became blocked, once again with large tree trunks and a mass of miscellaneous debris, including a trampoline from a nearby garden. The water level built up until the actual footpath across the Bridge itself became flooded. The Bridge, with its structure weakened by the growth of vegetation and the long–acknowledged need for re-pointing, was at risk once again. Luckily the rain stopped and the flood water subsided. 

Every credit must be given to the group of local people who gathered at the Bridge to free the arches once the flood had subsided and the river level lowered. This was a tremendous feat of local heroism. They cleared large fallen trees and a massive amount of debris so that the river could flow freely. There is, of course more work to be done to ensure the safety of the structure but the experience of mid-June shows that the authorities cannot rest on their laurels. This is the first lesson for Our Heritage from the impact of climate change.

The second lesson for Our Heritage is more contentious but remains a fact. We can draw lessons from the flooding experience of mid-June and revise some of our perceptions about what is best for Our Heritage.  This article includes the well known photograph of Caergwrle Castle on a bare, treeless outcrop. Whenever this photograph appears on social media it provokes a number of nostalgic yearnings for the days when the Castle could be seen, by all, for miles around. It also provokes comments about the desirability of cutting down the trees in order to achieve this idealised view of the monument once again.

These yearning are based on a misconception about what is best for the environment and for our community. Indeed, it is likely that a return to a barren hilltop, even if this were legally permissible within the Conservation Area, would pose a serious threat to homes in the immediate vicinity of Castle Hill within the current context of climate change. 

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The recent flooding caused serious problems along several roads which are adjacent to the lower slopes of Hope Mountain. A blocked culvert failed to carry water from Hope Mountain and caused the Mold Road to be closed near the junction with Pentre Lane. A vehicle was left stranded and there was a flood risk to local properties. Relief came when local people secured the help of someone with a digger who broke through a hedge in order to excavate a means of releasing the flood water from the roads. Llanfynydd Road on the west side of Hope Mountain was closed through flooding and people living in Gwalia, in Caergwrle, were mindful of previous flooding that has occurred there. Whilst Sarn Lane, Caergwrle, was flooded by water from the River Alyn, these other examples occurred at the bottom of an upland area which is partly farmed and not covered in trees. 

The significance of upland woodland is that, according to the Woodland Trust, the extensive root systems of trees allow for sixty times more penetration of rainwater into the ground itself than would otherwise be the case. A bare hilltop at Caergwrle would inevitably cause large amount of water to roll down the hillside with a serious risk of flooding of adjacent roads and homes. Indeed there are times when fallen trees on the Castle Hill have actually caused a flow of water to emerge from the sponge-like ground that has absorbed the rainfall.  Any tree-felling at all at the site has to be done judiciously and with consideration of the possible consequences.

The Welsh Government has now declared a Climate Emergency and has recognised that climate change threatens our health, economy, infrastructure and our natural environment. The bid to deliver a low carbon economy involves planting trees, rather than removing them. Flintshire Countryside Services have been ahead of the game with their Urban Tree and Woodland Plan for 2018- 2033.  This sets a target to establish urban canopy cover of 18% (as opposed to the 2013 figure of 14.5%) by 2033. Flintshire is currently the seventh lowest county in Wales in terms of tree canopy cover so there is a feeling that some headway needs to be made. The current trend is therefore to plant trees, rather than to remove them. To view Flintshire Countryside Service’s Plan, which has the approval of full Council, see:
​https://www.flintshire.gov.uk/en/PDFFiles/Countryside--Coast/Tree/Tree-Plan.pdf

The views expressed in this article are those of the author and do not reflect the policy of either Flintshire County Council or Hope Community Council. Readers are welcome to contact the author with any news or views on the local heritage at [email protected] or by telephoning 01978 761 523. ​