For the RSPB team at Strumpshaw Fen, flooding is a regular part of our lives but the last few days we have faced some extremely challenging flood events.
Last Saturday night and Sunday morning a tidal surge, driven by Storm Malik, pushed seawater up the River Yare, reaching a level of 1.40 m in the Environment Agency level gauge at Brundall. This is the highest level ever recorded, beating the previous record from Nov 2007 by 1cm! To put that into context, a river level of 1.40 m is 0.7 m above our lowest paths around the fen, and as a result many paths and the main fen areas were deeply flooded. A flood like this triggers a flurry of staff activity to keep people safe, and our warden Matt who was on duty carried out a number of urgent tasks to ensure nobody is trapped by floodwater, by closing off trails and checking the floodbanks and sluices.
Even the woods and meadows, which are protected behind flood defences, did not escape as water was seeping through and flowing over the banks into some meadow ditches. Floodwater over-topped the brickwork at the pumphouse which partially collapsed, allowing much water into the meadows in this area until some temporary repairs could be made. During Sunday evening and Monday we were relieved to see the water level in the North Sea and the Yare rapidly return to normal, allowing some water to drain off the fen, but a new storm (Corrie) brought a second surge tide on Tuesday, this time reaching 1.32 m in the River Yare and pushing water back into the fen.
Strumpshaw Fen nature reserve has the dubious distinction of being the most vulnerable fen habitat in the Norfolk Broads, due to its downstream location of the Yare. The water level in the River Yare at Strumpshaw is affected much more by the sea level than it is by rainfall. The floodwater can be very saline, and sea level rise is resulting in a worrying trend of more frequent and severe flooding. It is easy to imagine sea level rise as a slow change, getting steadily higher every year, and we have seen an increase in average river levels over the last few decades. However, the biggest impacts we see at Strumpshaw Fen come from storm surges, and climate change is predicted to result in an increase in storminess of weather. This impact of climate change is probably the hardest to predict.
The disruption to the reserve and the physical damage is a nuisance, but infrastructure can be repaired, and the reserve trails and hides will reopen as soon as the floodwater subsides enough. The real lasting damage is from the saltwater which kills fish and aquatic invertebrates and dependent bird species. Unlike most nearby fen areas, Strumpshaw Fen has a degree of isolation from the fluctuating water of the River Yare and the water level stability is the reason why Strumpshaw is the most important nest site for bitterns and supports the highest density of nesting marsh harriers and bearded tits in the Yare valley. Unfortunately, this isolation tends to trap saltwater after a flood, increasing its vulnerability. On Monday, warden Dominic measured salinity levels and found the highest level was around 50% seawater and though some parts of the fen were much lower, saline water had affected all parts of the fen and many ditches in the meadows. Since the big flood in 2007, the reserve staff have installed a systems of water control structures that allows us to flush saltwater out of the fen much more quickly than before, but even now it may take months and we expect to see some impact on wildlife during 2022.
Conservation organisations have understood the threat to freshwater wetlands along the East Coast for many decades, and for this reason have made an enormous collective effort to create new wetland habitats in less vulnerable parts of the country. This programme has already been successful in providing new homes for species like bittern and crane, but the less mobile species like the swallowtail butterfly, and the countless moths, beetles, flies, bees and other invertebrate species which depend on Fen habitat and many of which are restricted in the UK to the Norfolk Broads remain extremely vulnerable.
The nature and climate emergency affects us all - our families, our countryside, and the wildlife we love. But it's not too late to act if we act now. Together, we can make change happen. We can all do our bit to save nature, do the right thing for climate change, and work together to create a better world.
We need to show our leaders that actions speak louder than words. So we’re asking you to take an action for nature and share what you’ve done. Every action you take shows those deciding our future that you care about nature and the climate. It will help us demand that decision-makers follow our lead and take ambitious action for the nature and climate emergency.
Follow the link to find out how you can get involved https://www.rspb.org.uk/get-involved/activities/my-climate-action
Meanwhile we hope to celebrate #winterwetlands this month with a little less water around our ankles! And to share with you some of the conservation success stories from the Mid Yare Reserves. Please take the opportunity to follow our Facebook or Twitter page for more news.
(FYI: Strumpshaw Fen nature reserve remains open, woodland trail open, Fen trail closed from top of Sandy Wall, Fen Hide and Tower Hide closed, Hides will reopen as soon as the flood water recedes)
Many thanks to Warden, Matt Wilkinson for all images supplied.