By: Bonnie O’Farrell

Lough Neagh is the largest lake in the British Isles and supplies 40% of the drinking water for Northern Ireland. Despite this, it has been referred to as an ecological ‘sacrifice zone’ by many. The health of the community, people and environment has been sacrificed in the name of ‘economic development’ or ‘progress’. Ongoing pollution through farming and sewage, the active sand dredging of the lakebed and the spread of invasive zebra mussels have all caused extensive damage to the lake’s ecosystem, so why is nothing being done?  

The catchment of Lough Neagh occupies around 30% of the land area in Northern Ireland, it is primarily composed of agricultural land. In 1967, the first large scale bloom of blue-green alga would appear in the lake. This interfered with water treatment plans and the fishing industry, particularly the eel fishing industry. As a result, the Northern Irish government set up a freshwater Biological Investigation Unit, but this failed to adequately address the root of the Loughs problems. Blue-green algae are not actually algae but a type of cyanobacteria which fixes nitrogen, hence their affinity for nitrogen rich waters. They usually appear as blooms in warmer months due to their need for abundant sunlight. Climate change and increasing temperatures only worsen their effects when combined with pollution from multiple sources. 

Phosphorus is the main limiting factor when it comes to algal blooms and agricultural runoff accounts for around 61% of the phosphorus influx into the lake. This is a direct result of excess nutrient application as well as a disregard of the laws governing appropriate nutrient application. Urban sewage contributes a further 30.3% of the influx and the remainder comes from non-sewered rural populations. Studies done in Queens University reveal that 80% of the DNA in the algal blooms contained human faecal matter which confirms the presence of large amounts of untreated human sewage that is being allowed to enter the Lough.  

The largest outbreak of the algae to date happened in the summer of 2023. The scale of it could be seen from space and caused nationwide concern, it was a direct result of the government failing to take meaningful action to prevent what the public knew was coming. It caused the temporary, but ongoing, suspension of the wild eel fishery, which supported 14% of the entire EU wild eel catch annually. This has put many fishermen’s livelihoods at risk, and the decline of the eel population is concerning, considering the European eel is critically endangered. 

This did not only affect wild animal populations but also the people living in the area. Reports of “cancer clusters” came forward following the 2023 bloom, yet there was no intervention from The Department of Health. The only warnings given to the potential danger of the toxic fumes being emitted by the algal blooms were signs which were sporadically placed around the lake. This would suggest that DAERA, the Department of Agriculture, were the ones managing the crisis with no input from the Department of Health.  

The ownership of the lakebed is also cause for concern. While the contaminated water is belonging to NI water, the lakebed itself is owned by the Earl of Shaftsbury, Sand has been extracted from the lakebed for more than a century and has become a major business. Suction hoses are used and over a million tonnes of sand gets removed from the bed every year. Five companies were licensed to extract up to 1.5 million tonnes of sand from Lough Neagh in 2021, with The Earl of Shaftsbury receiving royalty payments for every tonne of sand extracted, around 30 million tonnes of sand have been extracted since the 2000s. But what is the sand used for? 30% of Northern Ireland’s construction sand comes from Lough Neagh and it is used in GAA grounds across the country. Croke Park is lined with thousands of tonnes of Lough Neagh’s sand and Homebase sells bags of recreational and building sand from Lough Neagh.  

Sand dredging disrupts sediment and releases heavy metals, nutrients and contaminants that were stored in the bed back into the water. This poses a threat to aquatic life and human health as it only worsens the already catastrophic effects of agricultural and sewage runoff. The increased turbidity reduces light penetration and interferes with photosynthesising plants. This leads to reduced oxygen in the water for animals and eutrophication due to excess nutrients, eutrophication blocks out light even further and creates a viscous cycle. This prioritisation of private profit over public health and environmental protection is a slap in the face towards the people of Northern Ireland and the animals that rely on the lake.  

Unfortunately, the Lough’s advanced state of eutrophy is not its only problem. Invasive alien species are the biggest threat to native biodiversity after pollution, and a population of the invasive Zebra mussel was first recorded in the Lough in 2005 when they were found on the hull of a boat which was moored there. Twenty years later, they have become established. The impacts of their invasion in Lough Neagh are complex and dynamic, one such impact being the changes in the food web and habitat structure. The mussels decrease chironomid populations near the shore, which reduces the food for birds such as the pochard, scaup, goldeneye and tufted duck; all of which rely heavily on the larvae during the winter months. Decreased body condition and growth of eels and pollan have also been observed as they are forced to shift from high energy prey, e.g., crustaceans and invertebrates, to lower energy zebra mussels. 

Eradication of Zebra mussels from an area as large as Lough Neagh is next to impossible, once they become established, there is little that can be done to control or eradicate them while still preserving the natural ecosystem. Efforts tend to focus on prevention of their establishment to begin with, which was done before the introduction into the Lough through signs and leaflets which were distributed to angling and yachting clubs, etc., but it was shown through surveys that boaters who had knowledge about the species and were informed on the prevention methods still did not inspect their boats, which led to the introduction. The government also played a role in the inevitability of invasion; plans were underway to reopen a canal link between the invaded Lough Erne and Lough Neagh in 2004, despite the certainty from ecologists that this would result in their spread. 

These issues combined lead us to the question: what can be done to restore Lough Neagh, even in part? This is clearly not just a result of government inaction, but the active facilitation by the government. A solution is that the Lough should be granted legally enforceable rights and brought into public ownership. While this sounds outlandish, it has been successfully done in New Zealand for the Whanganui River, which was granted legal personhood in 2017 under the Te Awa Tupua (Whanganui River Claims Settlement) Bill. By their law, the guardians are guided by a list of values to help them act in the rivers best interest. This was brought on by concerns for the rivers health and a desire to preserve it for the future, these are the same desires we have for Lough Neagh.  

While this approach would bring an end to the sand dredging, more achievable solutions are also worth investigating, given the unreliability of government bodies to bring in any large environmental bills. Public ownership may also not completely address the underlying issues or incentivise industries or agri-business to change their practices. A more realistic solution would be to require mandatory nutrient management plans for all farms and have regular audits to ensure targets are being met. A tactical plan must be agreed upon by farmers and society and it is crucial that farmers are educated on the benefits, not only for the environme.t but for their own livelihoods. It is vital that we recognise that the preservation of the Lough is not just about protecting a single body of water but preserving the intricate web of life that depends on it, that ultimately includes us. Ecologists and locals have been warning the government for decades, and it’s time to make them listen.