A broken stream, a 'dirty drain'. Is there any hope for the Glasheen?
A major ecological report into the Glasheen highlights how degraded, polluted and devoid of biodiversity the city stream has become. But that health status report also offers a lifeline.
If you don’t know the Glasheen Stream, that’s not surprising. From its source near the arches of the once-mighty Chetwynd Railway Viaduct on the Bandon Road to where it enters the River Lee at Victoria Cross, it runs just over 5 kilometres.
Along this route, which takes it from woodland and fields on the outskirts of the city, it is channelled, fenced off, hidden, laden with silt, culverted, tunnelled, bordered by a motorway, dredged, and used as a dumping ground. Water will always find a way downstream, and so it has with the Glasheen. But nature, by and large, has been forced to abandon the sorry stream.
The degraded state of the Glasheen Stream is hardly unique. Look around at many of the city’s waterways, and you’ll see the same grey, murky, slow-moving water that signals pollution, wastewater, and the exact conditions that create biodiversity dead zones.
Maria Young from Green Spaces for Health and the cohort of gardeners who have transformed a corner of Clashduv Park into a thriving community garden know the stream well. The Glasheen runs in a straight channel within spitting distance of the garden and polytunnel, where they grow radishes, lettuce, cape gooseberries, prickly cucumbers, tomatoes of all varieties, Jerusalem artichoke and much else. They have also dug out a pond, planted rows of native Irish hedgerow plants and published a cook book.
The Glasheen, however, is inaccessible, barricaded behind fencing.
The community gardeners have long known that the nearby waterway is an unhealthy environment. They conducted their own limited research, but following major flooding in the autumn of 2023, when the river burst its banks, they wanted to understand just how bad things were, and, just as importantly, what, if anything, could be done to improve conditions in the stream.
So Maria, knowing that very little gets done without funding, went in search of a source. She found it in the Local Authority Waters Programme, or “LawPro” as it is called by those in the know.
Over the course of several months in 2024, Letizia Cocchiglia, an ecological consultant from Mayfly Ecology, was commissioned to survey the Glasheen from its source to the Lee to gain a fuller understanding of the health of the water system.
The resulting report is comprehensive and sombre, laden with abbreviations, historical insights, Latin names for species, charts, maps, tables, and references to the myriad state bodies responsible for water, the environment, and mapping the terrain. It also doesn’t pull any punches.
Take this paragraph:
The water quality across the entire Glasheen Stream is very degraded. Just over one third of the stream length is seriously polluted (Q1-2, Q2) and this was so significant that at some sites very little macroinvertebrate life could be supported representing a complete breakdown of the trophic system.
Specialised language aside, the message is clear: this is the opposite of the painter’s and poet’s stream, bubbling with life, vivid and verdant.
Macroinvertebrates feature frequently in the Mayfly report, though not so much in the Glasheen itself. The presence of these backbone-less creatures, large enough to be seen without a microscope, is a key indicator of waterway health. They have varying levels of tolerance to pollution and are a vital food source within aquatic ecosystems.
The Mayfly report continues:
The results of the macroinvertebrate survey, the discoloured (grey) water, sewage fungus, low oxygen review of available water chemistry and other direct observations all show the Glasheen is not in a healthy state. In reality, the stream is functioning as an open drainage system for the direct discharges of untreated water from various sources. Not only does this have significant negative effects on water quality and biodiversity but potentially poses a public health risk. It is a truly shocking situation for a stream that has huge biodiversity and amenity potential.
Hope springs eternal, or at least it feels that way when you consider that otters have ventured along the banks of the Glasheen, and eels have made their way upstream. While no salmon or brown trout have been recorded in the stream for years, they have been spotted close to where the Glasheen joins the Curraheen and the Lee.
Perhaps what the Glasheen suffers from most is our apathy and inaction. When I told a friend I was writing this piece, his response was both illuminating and funny: “Is there a Glasheen stream???”
In a year of elections, manifestos, and promises, very few politicians, whether local or running for the Dáil, had anything to say about the stream. True, there might be bigger fish to fry, such as the housing crisis that has left over 15,000 people homeless. But when politicians and public officials speak of the environment and climate change, the Glasheen is far from abstract. It is a struggling, polluted waterway, right under their noses, running through their constituencies.
Neither seen nor heard
“Rivers need to be seen,” Letizia told me over the phone last week, after spending much of the latter part of 2024 in the Glasheen, taking samples and photographs, standing in beds of silt, observing pollution and wastewater, and occasionally catching glimpses of the stream’s former glory.
For instance, the upper part of the Glasheen, beyond the original “posh” Dunnes on the Bandon Road, is like “Eden.”
“I was so surprised,” Letizia said, describing how the Glasheen flows between rich, verdant vegetation and over a rocky substrate—a bedrock where flora and fauna could thrive.
“The water quality is not great, but there’s a lot of hope for it there.” Centuries ago, a large pond fed the mills which stood closely. The Glasheen likely owes its origin to the mill.
However, once the Glasheen meets the ring road, it becomes a problem to be managed and hidden.
As Letizia explained, this is primarily done by dredging, a practice that dates back to when the stream flowed through what was mostly fields and farmland. Those fields have largely been replaced by houses, roads, and commercial buildings.
“The idea is to get the water off the land as fast as possible and send it downstream. That idea comes from clearing land for farming.”
However, with the volume of water rushing downstream during heavy rainfall, the Glasheen simply cannot cope.
The City Council still dredges parts of the Glasheen, as it did just weeks before the last serious flooding. During Storm Babet in October 2023, as T+D reported, the Glasheen burst its banks as it entered Clashduv Park, pushing floodwater, and likely wastewater with it, right up to the doors of houses in the Riverstown Estate.
What’s more, with each dredging, the Glasheen is stripped of vegetation and its riverbed of substrate, creating ideal conditions for very little to grow or thrive. In its place, the riverbed becomes laden with large silt deposits, ecological dead zones. For the Glasheen, and likely rivers across the city, there are two issues at play: flooding and “bringing back the water quality”.
“These two things aren't in conflict with each other,” Letizia said.
“They work with each other. It's trying to convince people that we can help solve the flooding issue and the water quality issue and make it a better place for everyone if we just join these things up and actually they work with each other.”
Engineering solutions
Part of the flooding solution lies upstream. As Letizia said, there is space to let the Glasheen flood out in the upper reaches, where the mill pond once stood in the Ardarostig Woodland woodland area.
“Slow that water down instead of a big torrent coming down.”
On top of everything else, the Glasheen also suffers from a misconnection problem, whereby drainage systems are connected to the wrong infrastructure which in turn impacts on water quality. This is particularly exacerbated during heavy rainfall.
“The drainage system around there is just completely overwhelmed, and there's a lot of misconnections so there’s a lot of industries and houses connected to the river that shouldn’t be, or the drainage system is just so blocked that the foul water isn’t going to a waste water treatment plant, it’s getting diverted into the river and it’s getting overwhelmed even in very light rainfall,” Letizia told T+D.
As Letizia said, the network is crumbling and ageing, and because so much foul water is making its way into the Glasheen it doesn’t have a chance to recover, adding to the overall degradation of the water quality.
Fixing the water quality will require significant investment and serious effort from those with responsibility, especially the City Council, but there are clear examples of where local authorities are doing exactly this, as Letizia explained.
In Dublin, the Dublin Urban Rivers Life project, a collaboration between South Dublin County Council, Dun Laoghaire-Rathdown County Council with funding from the EU LIFE Programme, identified potential locations of misconnections along the Dodder where homes were inspected and residents informed of the results.
“They're also renaturalising the river, putting in ponds,” Letizia said, adding “it's totally doable.”
“We have the expertise in Ireland. We have examples of it being done in Ireland. It's just tapping into that expertise.” That and tapping into the will to get it done backed by the funding resources.
Fighting back
One current that is fighting back is a relatively new collective called the Cork River Alliance, spearheaded by Maria Young and Julie Forrester. As the name suggests, rivers are what unite the group, but the group also acts as an ally for rivers.
Over the phone, Maria said that despite the damning words of the Mayfly report, she was delighted with it, not for its findings, but for the hard facts it presents.
“There’s nothing like having a document like that in your hand that you can really show to politicians, local councillors, and residents,” Maria said. Besides, it’s not as if Maria was unaware that the news would be bad.
“We knew already there was something radically wrong with it, but it's great to get an expert to go in and get down and dirty, as it were, in the field, and really give you the feedback that you need to hear, to corroborate what you suspect is wrong.”
Beyond a drain, next steps
Maria said that the river group has a definite next step, which involves commissioning a hydromorphology company to examine the Glasheen.
As Maria explained, they would conduct a complete survey of the Glasheen and provide eco-engineering suggestions and recommendations, many of which are likely to be nature-based solutions.
“They would look at the topography of the river and at how we might restore its flow, like bringing the curves back to the river, in layman’s terms,” Maria said.
The other thing that the Glasheen really needs is a groundswell of support, especially from locals. Letizia believes that, for a generation of locals, the Glasheen is seen less as a living, breathing stream and more as a drain. Being barricaded behind fences has not helped its visibility or its potential as an amenity either.
On one small stretch of the Glasheen along Schoolboy's Lane, the stream is accessible. A narrow, open park with trees lines one side of the stream. Here too, the Glasheen has been engineered in a way that makes life hard for most species. The channel has been widened and straightened, and as Letizia’s report notes, “the substrate was dominated by deep black silts, with all coarse substrate having been removed.”
When Letizia was carrying out her survey work along Schoolboy’s Lane, she met a woman who told her she comes by almost daily to walk the path near the stream. It’s a quotidian act, but one that should surely be possible along many more stretches of the Glasheen.
On another occasion, Letizia met an elderly man at Clashduv Park, who inquired what she was doing. She told him about the survey, and he nodded along, only too familiar with the pollution that regularly affects the stream.
But then he said, turning towards ducks that had landed on the other side of the bridge, “It’s grand today.”
To which Letizia replied, “It’s grey,” pointing out the colour of the water.
“It’s not supposed to be grey, but to him it was just looking normal. It was stinky, you could smell the river. You shouldn’t be able to smell the river.”
“I really believe in making a river seen, because once it’s open and visible, people are walking past it, looking at it, noticing changes, noticing a pollution event, and noticing it’s degraded.
“On the plus side, they notice the ecology in it, they notice the ducks, the fish returning, and it becomes an amenity.”
Maria and the Cork River Alliance are determined to bring back the biodiversity that once existed in the Glasheen and to reconnect the thousands of people who live in and around the century-old stream with it. The first small but significant step is complete.
“I think if people just knew about it, they wouldn’t stand for it,” Letizia said. “People just don’t know what’s happening to the rivers in Cork because they’re so hidden away.”
Correction: An earlier version of this stated that in an election year, no politicians had raised the state of the Glasheen in their manifestos. However, Cllr Laura Harmon, Labour, has contacted T+D to say since her election to the City Council in the summer of 2024, she has consistently raised concerns about the impact of flooding during Council meetings. These concerns were also highlighted in her local election literature and in correspondence with residents of Clashduv and Riverview.
The full Mayfly Ecology report (2024) “Freshwater Ecology Survey of the Glasheen Stream in Cork City” by Letizia Cocchiglia can be found here.
For those interested in finding out more about the work of Cork River Alliance they can be reached at Corkriveralliance@gmail.com
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The Glasheen River was dredged to prevent flooding. It flooded anyway.
Between September 18 and October 5, Cork City Council carried out "emergency flood prevention works" on the Glasheen River in Togher as it flows in a straight line along the western edge of Clashduv Park and parallel to Riverview Estate.
Great Article JJ: thanks for signposting to the report too.