Conwy Silent Waters: The Tale of four Welsh Mussels
"Exploring the Depths of Conservation: Join Cragen Gleision and her companions on a quest to protect and conserve the quality of Afon Conwy"
This is the story of Cragen Gleision (mussel) and her three friends, Metel, Llif and Dafad, at the heart of the Conwy estuary, located in North Wales, UK. North Wales is home to a divine and green landscape, maintained through the temperate climate and precipitation. The picturesque region is renowned for its stunning natural beauty and rugged mountainous landscape, where the pristine water flows with tranquillity and majesty. Yet beneath the surface lies the hidden truth, a silent threat concealed that imperils their existence. Allow Cragen Gleision and her friends to tell their story on this pressing issue, a harsh reality that must be recognized and mitigated. As Cragen Gleision and her friends embark on a mission to advocate for their home, to shine a light on the dangers and educate others about the importance of preserving our water. Their story of resilience and hope show the prevalence of the community and conservation efforts.
! A voice must be made for Cragen Gleision's story !
Afon Conwy
Images portraying the breathtaking scenic views of the Conwy Welsh landscape
The Conwy River, Afon Conwy in Welsh, located in the United Kingdom. The river flows through the Conwy Vale, located in the prestigious Welsh mountain region, Snowdonia. Originating from the Migneint Moor and ending the Irish Sea, the Conwy is a combination of multiple tributaries.
At a smaller and closer level, the Conwy from its source until its final discharge is a total of 55 km in length. Draining a total area of 678 km², the river maintains a high flushing period, meaning sediment and pollutants do not stagnate as excessively as other rivers in the UK.
The Conwy estuary is the mouth of the river, exiting into the Irish Sea. A partially enclosed water body, where fresh and marine water are interconnected, creating a unique and diverse environment. This area is home to many species, adapted to both marine and freshwater sources, including, Mytilus edulis, the common blue mussel.
Mussels at risk
Scientific drawing of Mytilus edulis completed by Evy Mansat Gros, as a part of Marine Biology Practical 1 module course.
Cragen Gleision and her friends are marine blue common mussels (Mytilus edulis) located on the estuary bed. These are marine bivalve molluscs that are subject to commercial use in addition to aquaculture. These species are native to the North Atlantic, only being found in these waters. The distribution of these species is being affected by anthropogenic activity causing migration into new habitats.
Mussels are filter feeders, consuming suspended particles, and sediment available in the water column. Using ctenidia for suspension feeding, mussels can generate water currents to remove suspended food particles to digest. The syphon is extended out of the shell capturing the food particles, then using the gill layered structure as small filters.
The accumulation of these contaminants in the river water poses significant risks on the health of the mussels. Consuming contaminated mussels can lead to serious health issues, including cancer and various diseases, due to the bioaccumulation of toxic substances, a commercial issue affecting the local economy.
Mussel Filter Feeding Example
Water quality
What are the hidden issues disguised under the beautiful clear water of Conwy River?
Story of Metel
Far upstream, in the moorlands, the Hafna Mine remains are still preserved today. Being one of the most important lead mining areas in the UK, much of the Lead and Zinc is exposed to the environment. This non-operated mine still releases significant amounts of heavy metals that reach the mouth of the river in very little time, especially during flooding season. Metel, located in the Conwy estuary has been affected by heavy metals for several decades causing poor health and potentially carrying diseases.
Story of Dafad
Dafad, Cragen Gleision's childhood friend is today severely affected by the depletion of oxygen in his environment, as well as blocking out sunlight. The rural areas surrounding the Conwy River are mostly agricultural land (sheep, cattle and crops). A fair amount of the land is consumed by farmers who use pesticides composed of high nitrates and phosphorus.
Heavy concentration of nutrient discharge is found to reduce the fitness of mussels, causing lysosomal membrane instability as well as a significant stress factor.
Story of Llif
Moving closer to shore an additional issue affects water quality in the Conwy. Due to recent global warming, there is an increase in annual floods, increasing the number of storms that bring in oils and plastics. Llif, a recent mussel has begun to filter the contaminated water, affecting his inner structure and functionalities.
Story of Cragen Gleision
Finally, Cragen Gleision comes to share the largest impact of all, wastewater, and raw sewage runoff. North Wales, has a widespread population which has an implemented sewage system that is not often maintained and modernised. Any stress caused by flooding concludes in small raw sewage leaks into freshwater bodies. Raw sewage runs for more than 350 hours yearly into the Conwy River, containing harmful substances to Cragen Gleision.
Who would want to feed on raw sewage? Not Cragen Gleision, and definitely not you!
Mitigation
Heavy Metal flow into the river
A simple way to reduce heavy metal flow into the Conwy River is through a Acid Mine Drainage (AMD) treatment. Treated by adding alkaline substances to stabilise metals and reduce solubility, preventing further contamination. This treatment may involve settling tanks or filtration units to remove heavy metals from the contaminated water.
Eutrophication due to agricultural runoff
Eutrophication (algal blooms) due to agricultural runoff can be maintained by the simple implementation of Vegetative Buffer Strips. The technique uses strips of vegetation planted along the perimeter of agricultural fields, acting as a barrier between water and the cultivation land. Buffer strips reduce the transport of pesticides and excess nutrients to the river, contributing to the mitigation of agricultural runoff. This is a simple filtering method that is currently not practised in the Conwy Valley.
Sewage holding tanks (a) and an overflowing sewer in the city consequence of flooding stress on sewage pipes (b)
A simple solution to the excess flow of sewage would potentially be to delay sewage input into the river, done by sewage holding tanks, requiring investments. North Wales is structured through a combined sewer system, where road runoff and household wastewater is combined. As flooding increases, the water is mixed in the same pipes, causing an increase above the threshold of the pipes. Hence, pressure must be released, and this is through sewers in the city, releasing raw sewage in addition to outfall pipes in rivers.
Sewage Overflow discharge 2022 due to storms and overflooding
To reduce wastewater runoff, sewages must be impermeable, therefore a simple test can be conducted to ensure this is the case. Balloons are placed at a certain distance from each other, through the sewage channel, then air is injected into the canal. This solution is simple, and cheap, offering the possibility to reduce small leakages using air.
Oil Resistant Pipe Plug, Multi-Flex® 1 3/4" And Larger, With & Without Bypass, 114 & 115 Series The instructions are relevant for all Petersen Multi-Flex Inflatable Plugs.
All infrastructure and installations must be in good condition to function adequately, requiring electricity, a good and constant source, with a secondary power system in the event of a power shortage. Water treatment stations must be maintained daily, in terms of concrete structures, air systems (air compressors) and all tank installations including pipes.
Community Effects
Mussels have often been used in projects to treat sewage, cleaning the water through their filter feeding system. However, mussels can't be used to treat raw sewage in a natural environment and then used for economic purposes. Today mussels in the Conwy estuary are affected by the freshwater quality that they have become Class B species, unable to be transported to mainland Europe, a severe economic impact to local fishermen and the country's global economy.
EU bans the importing of live Class B bivalve molluscs from UK
After conversing with local fishermen, it's evident that many are oblivious to the underlying impacts of freshwater quality affecting mussel populations. Mussels stand as an emblem of Conwy and Wales, drawing tourists to the region.We must extend support to increase awareness and address the factors affecting mussel sustainability. This video was filmed in 2016, since the health of the mussel population has significantly declined. Mussels are less prevalent and much more likely to contain contaminants that will affect the human population who's diet includes Conwy mussels causing diseases and cancer.
Conwy Mussels Welsh GI Food Story - Stori Bwyd GI Cymru Conwy Mussels
Local fishermen who are close to retirement have witnessed the detrimental effects of time, reminiscing about an era when mussels thrived in health and sustainability. Once classified as Class A, they were a cornerstone of economic success in European countries such as France. This is a poignant reminder of the urgent need to address the challenges of water quality threatening ecosystems and the livelihoods who depend on it.
Gap Analysis
Education and awareness
The local population and organisation are currently unaware of the ongoing situation in the Conwy River, even Welsh Water, wastewater services. There is no active record of how much untreated sewage runoff into the Conwy River or the marine system. From individuals to governmental corporations, the community must be engaged through education. This requires staff and volunteering opportunities.
Research funding
There is a severe lack of research, from heavy metal flow, agricultural runoff to sewage input. Bangor University has started to actively collect data; however it is difficult to analyse changes and due to the lack of preexisting data, in comparison to other rivers in the UK.
Improper management and maintenance
Sewage stations must be maintained; this requires funding to cover the cost of the maintenance as well as staff, workers who are trained to maintain and run the system. Due to the economic status of the UK, funding is limited, and tax rates are unable to increase due to financial constraints stemming from limited individual wealth.
Financial Constraints
All mitigation methods require a certain amount of funding, from cheaper to more expensive solutions. Compared to larger cities such as London (36.7 Median Age), Geneva (39.5 Median Age), New York (39.2) or even smaller similar cities such as Chester in the UK (42.5 Median Age) Conwy remains a heavy elderly population (50.3 Median Age), with mostly retirees unable to fund the modernisation of sewage plants.
A call to action
Want to learn more?
Viral dispersal through the river-estuary-coastal continuum in the Conwy catchment
Become an advocate for Cragen Gleision and her friends! Stand with them in their mission to preserve this natural resource for generations to come. Every voice matters in the fight for environmental conservation.
"Mewn pob daioni mae gwobr"
