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Breaking the Banks: 'Vicious circle' of public works 'degrading' Ireland's rivers

While the Office of Public Works says it is reducing the impact of arterial drainage work, waterways and their habitats “are still suffering”.

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IN THE MIDDLE reaches of the River Clare in Galway, where now lies agricultural grassland, there once was one of the biggest turloughs in Ireland, where tens of thousands of geese and whooper swans would flock every year.

Ecologist Dr Will O’Connor of Ecofact Environmental Consultants told Noteworthy that the turlough system, which included a former lake called Clonkeen Lough, was drained and erased from the landscape as part of extensive arterial drainage works in the Clare River catchment. These works, which first started in the 1700s, gained impetus with the 1945 Arterial Drainage Act.

What was once a “beautiful river” and “probably the most diverse river catchment in Ireland”, with islands, side channels, marshes, turloughs and seasonal lakes all the way along, as well as salmon and eel, has become “one of the most modified rivers in Ireland”, he said.

“You’d want to see the river now. It’s the worst example of a straight, channelised river, cut down into its bedrock, arrow straight.”

Growing up in the ’70s and ’80s in Tuam, Co Galway, O’Connor never got the chance to see first hand what the Clare River was like before it was arterially drained. But when he was out on the river he would sometimes meet older anglers who remembered the river before the drainage.

“They would tell me what the river looked like then. A lot of the reason I became an ecologist was because I became aware of what was lost in the Clare-Galway river catchment.”

In the ’90s, he saw machines returning to do arterial drainage maintenance. “I saw it was not just the original scheme, it was this ongoing maintenance that kept degrading the river channels as time went on,” he said.

“It’s a vicious circle of creating riverbanks that are eroding, rivers that are getting wider and shallower. Then there’s more light getting to the bed of the river so there’s more vegetation growing. There’s more runoff from the drained areas in the catchment. And they’re just feeding this vicious circle and slowly degrading rivers every time they come in to do this maintenance work.”

Will O'Connor wearing a jacket and trousers standing on a cement platform beside a river with a weir in the background. Dr Will O'Connor says that rivers continue to be degraded by maintenance work Brian Arthur Photography Brian Arthur Photography

O’Connor is one of many experts who shared their concerns with Noteworthy over the state of Irish rivers and the impact this is having on wildlife that depend on them. In this investigation, we look at vegetation clearance processes along the banks and in the channels of rivers in Ireland.

Based on almost 200 documents released under Access to Information to the Environment (AIE) requests as well as interviews with researchers, farmers, State agencies, environmental groups and campaigners, we can reveal:

  • Riparian habitats and rivers are being destroyed in Ireland, according to experts, who are calling for the Arterial Drainage Act to be revisited and updated
  • Recent arterial drainage work by the OPW in contravention of the Wildlife Act
  • A quarter of OPW audits of maintenance works last year failed to obtain a ‘good’ or ‘very good’ score
  • Instances where required environmental assessments were done after the vegetation was cleared
  • Long-lasting damage to the Clare River from arterial drainage activities
  • Negative impacts of arterial drainage on fish populations in Cork

Many sources expressed serious concerns over the environmental impact of arterial drainage maintenance activities, a practice the Irish Wildlife Trust has said “resulted in the destruction of whole river systems”.

In the past, arterial drainage activities without strict conditions in place resulted in “widespread riparian degradation throughout the land,” said Professor Simon Harrison.

His research in UCC on freshwater biology includes looking at the impact of nutrients and pollutants on streams and lakes in Ireland. This includes riparian habitats – the banks of a river and the land or wetlands that run alongside it.

“Waterways are still suffering today, but they are a bit more protected,” he said.

‘Dredged and drained’

“There is no authority for rivers in Ireland,” according to Cian Ó Dónaill, Assistant Chief Engineer with the Office of Public Works (OPW).

A number of bodies are involved in the maintenance of Irish rivers, including the OPW, local authorities, Waterways Ireland (WI), Inland Fisheries Ireland (IFI), National Parks and Wildlife Service (NPWS) and the Local Authority Waters Programme (LAWPRO).

The OPW is responsible for maintaining about 11,500km of channels in 33 catchments under the Arterial Drainage Act. Local authorities are responsible for about 4,500 to 5,000 km of channels under various arterial drainage acts prior to 1945, said Ó Dónaill.

Arterial maintenance – which is separate from the OPW’s flood relief schemes – includes maintaining vegetation on the channels, both on the banks and inside the channel.

Three tree stumps with ivy growing on them on the banks of a river. Trees and branches cut near Drewstown House in Co Meath where OPW carried out maintenance last year Maria Delaney Maria Delaney

Silt, weeds and vegetation are typically removed from the channel, said Nathy Gilligan, Head of the OPW’s Environment Section. In addition, trees “that are blocking the flow” and overhanging branches “to known flood level” are removed, according to the OPW’s environmental guidance notes.

The programme for arterial drainage maintenance follows a five-year cycle. Each year, the OPW maintains about a fifth – equivalent to about 2,100 km – of the channels.

“The State historically executed these large catchment-based drainage schemes,” said Gilligan. Rivers, he said, are now lower than they should be in nature.

About one sixth of rivers in Ireland were dredged and drained by the State, so what you have now is a modified or unnatural situation. We maintain unnatural rivers in the first place.

The early arterial drainage scheme widened and deepened channels and tributaries to drain and benefit agricultural lands. Rivers were “horrendously damaged from the 1940s and ’50s onwards through the arterial drainage scheme”, said ecologist O’Connor.

The 1945 Act doesn’t refer to the environment, and the 1955 amendment is the first time that ‘environmental surveys’ are mentioned.

Ó Dónaill said that in the past “the channel would have been subject to very heavy maintenance where both sides of the channel would have been subject to maintenance, [including the] riverbed”.

The work we do now is unrecognisable [compared] to the work we would have done 20-30 years ago.

Currently, there are two objectives to arterial river maintenance and vegetation clearance, said Gilligan: one is to provide outfall for drainage, which involves maintaining the depth of the channels to allow adjoining lands to drain into it.

“If we let the channel rise, it’ll start to upset the drainage and reduce agricultural productivity” on about 260,000 hectares of land, he said.

The other is maintaining “channel capacity”, according to Gilligan.

“There are about 22,000 properties on the benefiting lands, so if we let the channel capacity reduce, that will start to increase the flood risk to all these other towns and villages,” he said, adding that the only other reason vegetation would be maintained is to facilitate machine access.

“We do try to leave as much vegetation as we can, while undertaking our maintenance duties to allow some conveyance capacity in the channel or the drainage outfall,” said Ó Dónaill. However, he said, “most landowners are unhappy because they feel we are not doing enough.”

“I can see a huge shift in the OPW,” said Gilligan. “At senior management level, there is quite a significant focus on the environment,” he said, also noting that the OPW collaborates with Inland Fisheries Ireland (IFI) on carrying out enhancement works on rivers.

Our investigation found that the OPW have over 3,300 records of protected species from the channels they maintain, including otter holts, lampreys, badger setts, whiteclawed crayfish, and swan and duck mussels. Two thirds of these records are less than 10 years old, the remaining one third are 10 to 30 years old.

Works outside tree cutting season

However, damage to rivers continues to take place. We examined numerous OPW internal audits released to Noteworthy through AIE and found several recent instances where tree management had taken place “outside the tree cutting season”, contravening the Wildlife Act.

On the left is clay along cleared river banks with a blue digger in the background. On the right cut branches are left on the bank with a tree and domed building in the background. OPW audit showing 'damaged form of channel' as well as trees cut and 'left on bank to re-enter channel' OPW Audit June 2021 OPW Audit June 2021

One such instance was documented in an internal audit from June 2021 of the OPW arterial drainage works taking place in the River Brosna, near Kilbeggan Distillery, Co Westmeath. The audit scored an overall 15% (‘Bad’).

All machine crews are typically audited once a year, according to the OPW’s Gilligan. Random audits have increased from 20-30 to 70 a year, with about 50 done by external environmental consultants and 20 by the OPW environment section. Audits are also conducted following complaints or reports of problematic work.

Most audits seen by Noteworthy scored favourably, but 15% (11) of the 71 audits in 2020 and 25% (13) of the 52 audits in 2021 did not obtain a ‘good’ or ‘very good’ score.

Under the Wildlife Act, cutting, grubbing, burning or other destruction of “vegetation growing in any hedge or ditch” between 1 March and 31 August is prohibited.

The audit of the River Brosna had “no positive aspects to the report”. It noted that the OPW driver doing the work had “no regard for the tree cutting season” and made “no attempt to keep any vegetation”. It also found that “no assessment took place”.

A spokesperson for the NPWS told Noteworthy that Section 40 of the Wildlife Act restricts the destruction of vegetation on uncultivated land. “This makes it an offence to destroy vegetation growing on uncultivated land in a hedge or a ditch between the 1st of March and the 31st of August each year. There are a number of exemptions relating to public health and safety and to work carried out by Inland Fisheries Ireland. No specific reference is made to works carried out by the OPW.”

Branches lying on ivy covering the river bank between two trees that remain standing. Cut branches still lie on the banks of the River Brosna where OPW works were carried out last year Maria Delaney Maria Delaney

The works were done to remove timber blockages “causing a potential flood risk to the apartments adjacent to the river”, an Engineer’s Report states. The audit was requested after the works were seen by an IFI ranger.

After the poor result, the driver was re-trained and a second audit four months later, scoring 75%, found a “great improvement from the previous audit”.

“There was a huge effort put in by the organisation and the approach of that driver totally changed. He was re-audited to confirm that,” said Gilligan.

Another audit, which scored ‘poor’, took place in March 2021 in the Owenlobnaglaur River, part of OPW’s Moy scheme. The audit found that works had been done in the fish spawning season (end of September to beginning of June), with potential impacts on fish as well as damage to riparian vegetation in the bank.

You can search for and read all of the OPW audits from last year in this table

Permanent changes in habitat

Several independent strands of research show long lasting damage to Irish rivers from arterial drainage maintenance programmes, our investigation has found.

In 2021, Eoghan Concannon, as part of his MSc in Environmental Leadership at NUIG, studied the impact of 1954-64 arterial drainage activities on the ecology of the Clare River catchment in east Galway.

Concannon, whose grandfather used to work on the drainage scheme in the 1950s, has close ties to the river. It was “a very different place before and after the drainage work”, he told us.

He found “a significant, negative and long term impact incurred by this drainage programme on the river’s ecology”.

A group of researchers wearing waterproofs including wellies standing in and beside a small stream. One researcher is hunkered down taking measurements. Eoghan Concannon (taking measurements) and colleagues conducting hydromorphology research in Co Sligo Eoghan Concannon Eoghan Concannon

His research identified several negative impacts of the scheme on multiple species, including mayflies, stoneflies and caddisflies, aquatic plants, fish, aquatic mammals and birds. Riparian vegetation and woodland were also removed from the bank during the works, he said.

“The shape and physical characteristics of the river were profoundly altered by the works, because the river lost its natural features such as meanders, in-stream material and riparian zones,” he said.

“There have been significant changes to the orientation and conveyance capacity of the Clare River for circa 200 years,” an OPW spokesperson told Noteworthy. “The OPW has a statutory maintenance responsibility for these works and has maintained the Clare river catchment for the past 60 years.”

In the late 1950s and early 1960s, the OPW’s Corrib Clare Arterial Drainage Scheme further altered the channel, widening and deepening the existing channel and tributaries with the purpose of providing outfall for the drainage of agricultural lands, the spokesperson added.

Recently, IFI and the OPW have been implementing river enhancement works in the Clare River, with the final tasks scheduled to be completed in summer 2022.

Large stones in a semi-circular line on both sides of the river, with gravel filled in behind these to narrow the river. Structures placed in a tributary of the Clare River (Corrib Catchment) last summer Inland Fisheries Ireland Inland Fisheries Ireland

There are both long- and short-term impacts of arterial drainage works, said Dr Micheál O’Cinneide, Director of CorribBeo and former director of the EPA.

Short term impacts – such as sedimentation – affect water chemistry, but rainfall and flow can enable this to recover within months or years, he said. 

In the long term, there are impacts on hydromorphology – the shape or physical form, conditions and processes of a surface water body – which is “a permanent change”, and on biology.

“The biology can take decades to recover and in this case [Clare River], some of the fish stocks have recovered but many have not. So that’s a permanent loss.”

A straight section of river with banks with low grass and little other vegetation on both sides. A section of Clare River surrounded by agricultural land Eoghan Concannon Eoghan Concannon

Draining works ‘as bad as pollution’

Long-lasting negative impacts of early arterial drainage maintenance activities were also identified by Harrison and his student Cassie McAree at UCC, when looking at trout populations in a local stream in Cork.

This stream was extensively dredged, straightened and deepened in the 1960s, he said. Now “it’s very much an altered habitat, but it does seem to have recovered.”

When they looked in the main stream channel and in the tributaries, they found that tributaries that were polluted had very few fish in them. But what surprised Harrison was that “the trout really, really don’t like living in this straightened, channelised stream”.

“Even 50 years on, the trout populations have not recovered in that stream. Drainage works on the stream channel seem to be at least as bad as pollution for fish.”  

When a big flood or pulse of rainwater happens, it will flow much faster down the straightened channel and the fish will not have any refuge, he said.

Straight section of river in the background with quote from Prof Simon Harrison - freshwater biology in UCC - For the fish a straightened river is just not a very good habitat. It's like standing in the middle of a motorway with cars rushing past, there's no way to get out of the flow. Photo - Maria Delaney Photo - Maria Delaney

Riparian habitats have a number of important functions, professor Mary Kelly-Quinn told Noteworthy. These range from stabilising the banks, to providing food resources for rivers in the form of leaf litter but also terrestrial insects which are part of the diet of fish such as trout.

Riparian vegetation also provides shading, said Kelly-Quinn, whose research in UCD focuses on human impacts on water resources. “While shading can be excessive and impact on primary production, some degree of shading is beneficial, particularly in the context of climate change, where it can ameliorate any likely increase in water temperature,” she noted.

Other functions include that of capturing pollutants, particularly if vegetation is mixed, she said, explaining that lower vegetation, such as grasses, will be effective at capturing sediment, whereas trees will be able to capture nutrients from groundwater, for instance.

“Riparian vegetation is also a natural habitat for terrestrial fauna [and] the adult stages of some aquatic insects.”

Kelly-Quinn said that “ideally we should retain riparian vegetation”. She added that ”it doesn’t necessarily have to be continuous” but in some areas, for example where slurry could flow off a field, “it’s important to have a buffer of riparian vegetation at those points”.

Kingfisher sitting on a small branch. It is a small bird with a large pointed beak with striking bluish green back and wing feathers, and a reddish orange front and eye stripe. Riparian vegetation is important for kingfishers Shay Connolly Shay Connolly

Riparian vegetation is a very important type of habitat for many birds such as kingfishers, said Niall Hatch, Public Relations, Branches and Development Officer with BirdWatch Ireland.

“At a time when Ireland is acknowledged to have a climate and biodiversity emergency, from our point of view, streamside vegetation has a significant role to play. There are many, many different bird species that use it, not just birds people might typically associate with water, but also many, many different species that often you’d [also] find in hedgerows.

“In Ireland, we don’t have a very good track record of protecting and cherishing our wetland habitats and this [riparian habitat] is another form of wetland habitat. So I think it’s important that it’s properly recognised and protected.”

The OPW ‘its own competent authority’

In order to prevent damage to habitats such as these, public authorities must undertake Appropriate Assessments (AA). This includes screening all plans and projects by a public authority to ensure that there is no adverse impact on the conservation objectives of a Natura 2000 site – a European-wide network of core breeding and resting sites for rare and threatened species.

A NPWS spokesperson told Noteworthy that “many rivers and streams in Ireland are not in, or hydrologically connected to, designated sites”.

However, they added that if the proposed activity, such as arterial drainage, “screens in”, the public authority must ensure that a full AA is carried out which includes a Natura Impact Statement (NIS).

All works, “including drainage”, also need to be in line with the National Biodiversity Action Plan 2017-2021 and the national River Basin Management Plan, as required under the Water Framework Directive, the NPWS spokesperson said.

The OPW works with a national framework of five-year duration Appropriate Assessments for all its catchments. “There’s no separate assessment for vegetation management,” said Gilligan.

All catchments go through a screening for AA. “If there is a possibility the [work] will impact on a European designated site, they go through AA which involves the production of an NIS. The final decision, what we call the determination, is on our website,” said Gilligan.

When it comes to the AA decision-making process, ecologist O’Connor said he was concerned that the OPW was making its own decisions and screening determinations, acting as “its own competent authority”. This was a concern expressed by a number of sources who spoke to Noteworthy

“The majority and any complex screenings are always carried out by external consultants,” the OPW’s Gilligan said. But “for very localised” and “not very complex” projects “we may carry out the screening ourselves, and that’s reviewed by our own in-house ecologist”.

He added that according to Habitats Regulations, the OPW is the competent authority for AA decisions.

So ultimately the decision does rest with the Commissioner of Public Works. But in reality, we do statutory consultation with NPWS, we don’t have to but we consult with IFI, and there is public consultation from now on anyway.

For “non-typical works”, an Environmental Risk Assessment identifies where a site specific AA is required. Every five years, the OPW also undertakes a Strategic Environmental Assessment, a program-wide assessment which includes public consultation.

Some experts we spoke to questioned the adequacy of these assessments. All the works should require site-specific ecological assessments, said O’Connor of Ecofact.

In 2008, a report by O’Connor, commissioned by the OPW, concluded: “The current strategic approach being developed by the OPW to assess the ecological impact of drainage maintenance works is insufficient due to the complexity of channel types, habitats and species potentially affected by these works.”

Works without environmental assessment

Our investigation found instances where vegetation clearance works were complete without screening or assessment or when the period covered by the Natura Impact Statement had elapsed.

Our AIE requests revealed that trees along the Abbey River in Limerick, within the Lower River Shannon Special Area of Conservation (SAC), were felled without any screening or assessment in early 2020 by a company contracted by Waterways Ireland.

On the left there is lots of vegetation on the right back of the river, including a number of willow trees. On the right, all of this vegetation is now gone and the bank is bare - mainly brown with some small green patches. Before and after views of the Abbey River from O'Dwyer Bridge in Limerick Left - Google Street View (2018) & Right - Abbey River Ecological Assessment via AIE Request Left - Google Street View (2018) & Right - Abbey River Ecological Assessment via AIE Request

A Waterways Ireland spokesperson said the reason for the works was the “removal of trees and scrub below the bridge in response to local concerns regarding dumping, litter and anti-social activity”.

“An ecological assessment should have been completed in advance of this work, as well as a Screening to inform Appropriate Assessment. The absence of these assessments was remiss,” they said. Waterways Ireland “commissioned an external ecological consultant to undertake a retrospective impact assessment”, said the spokesperson.

This retrospective ecological assessment considered the impact of the works to be “temporary” and to have not undermined “the conservation objectives of the Lower River Shannon SAC”.

However, it also identified a “loss of riparian woodland”, and highlighted that this “linear habitat does provide an important function in terms of woodland connectivity within the Lower River Shannon SAC”.

More than 10 tree trunks side-by-side cut down almost to the ground on the river bank. The affected habitat was riparian woodland mostly composed of willow, according to the ecological assessment Abbey River Ecological Assessment Abbey River Ecological Assessment

A Waterways Ireland spokesperson told us it undertakes “necessary vegetation cutting” within its property boundary to maintain infrastructure and amenity features. They also maintain encroaching vegetation within the margins of the navigation channels, or where vegetation is impeding flows to navigation.

‘Confusion’ over timeframe

Through our AIE requests, we also found that OPW works took place in the Trimblestown river channel, within the River Boyne and River Blackwater SAC, outside the period covered by the required Natura Impact Statement (NIS). These works occured in January 2021, with the NIS for the Boyne catchment covering 2016 to 2020.

Internal NPWS email correspondence following “a report of works” taking place in January 2021 – obtained by Noteworthy through AIE – states: “The current NIS for the Boyne Arterial Drainage Scheme appears to be out of date as it cover[s] a 5 year period from 2016-2020.”

A bank of gravel with small bits of greenery coming through it sits beside a river. There is vegetation on the other side of the river and some trees in the background. Part of the stretch of the Trimblestown river channel where the OPW works were taking place last year Maria Delaney Maria Delaney

This correspondence goes on to detail the NPWS visit to the site and interaction with the OPW. It concludes: “There appears to be some confusion as to the timeframe covered within the current NIS for the Boyne Arterial Drainage Maintenance Scheme.

“The document itself states that it covers a 5 year period from 2016-2020. However, the Environmental Section of the OPW are under the impression that the document timeframe does not need to be rigidly followed and that works undertaken in 2021 are covered under the current NIS and AA.”

“It has not necessarily expired on 31 December. There is a five-year period and we hope to get around to updating them. The next one wasn’t finalised. It’s not a hard and fast date,” said Ó Dónaill, the OPW’s Assistant Chief Engineer.

“The nature of the work doesn’t change,” said Gilligan. “Whether it’s the 31 December one year or 1 January the following year, it is not a construction site or new site. It’s the same works that have been going on in the Boyne for the last 50 years.” He added: 

On a five-year basis we update and revise the AAs but the essence of the AAs doesn’t change.

Compilation of four photos - two from 2010 showing lots of vegetation, including trees, along the river - and two from 2022 with the same views but with some trees and vegetation no longer there. Changes to banks of the Trimblestown river channel in Drewstown Co Meath between 2010 and February 2022 Above - Google Street View (2010) & Below - Maria Delaney via Noteworthy Above - Google Street View (2010) & Below - Maria Delaney via Noteworthy

Concerns over transparency

Elaine McGoff, Natural Environment Officer with An Taisce said “there’s a critical lack of transparency in what procedures they [the OPW] are following, what their decision-making process is.” 

An Taisce “have significant concerns about the ecological impact” of OPW works “and there’s no indication that they’re willing to change those anytime soon”, she added. 

McGoff also noted that the appeal mechanism is not clear. When asked by Noteworthy, the OPW’s Gilligan said if people are not happy with the works, they “have the power” to take a judicial review against decisions.

These concerns are shared by O’Connor, who said the areas where the works are taking place should be made publicly available in advance, and there should be a mechanism to review or comment on the works in advance and review the assessments and mitigation.

A change in Irish law in June 2021 has made public consultation a very clear statutory requirement, and Gilligan said that all NISs “now go through public consultation”.

Cut tree trunk beside a river in the background with a quote by Elaine McGoff, natural environment officer with An Taisce - An Taisce would have significant concerns about the ecological impact of what the OPW is doing - that the necessary safeguards just aren't in place. Photo - Maria Delaney Photo - Maria Delaney

Stronger laws needed

During our audit analysis, Noteworthy came across an incident where a farmer was “thought to have maintained and overdeepened sections of channel”. The audit noted “potential impact on [the] adjacent bog”.

When asked what the OPW does when landowners have carried out work, a spokesperson for the OPW told us that such a scenario “is rare”, but added: “While all activities in waterways are subject to compliance with water pollution and fisheries legislation, currently there is no statutory procedure specifically to manage physical alteration of waterways.”

The current Draft River Basin Management Plan for Ireland 2022-2027, which was published for public consultation by the Department of Housing, Local Government and Heritage (DHLGH) states that ‘controls on pressures that impact on the physical condition of waters need to be strengthened in Ireland’, the spokesperson said, adding that:

“The D/HLGH proposes to ‘develop a new Controlled Activities for the Protection of Waters regime to address pressures on the physical condition of waters’ which will establish a new legislative framework that all parties including private landowners and public authorities such as the OPW will be obliged to comply with.”

The same draft plan also states that “it will be necessary to develop new legislation, including the development of a Bill and associated secondary legislation aimed at managing hydromorphological pressures”.

Nature-based solutions

There is some work happening around Ireland to restore rivers to a more natural state.

Trish Murphy, Project Officer with the Inishowen Rivers Trust, has been working on restoring and repairing rivers in Donegal from the effects of erosion.

While the rivers she is working on in Inishowen were never arterially drained, many of them were dredged, cleared and straightened in the past by landowners and local authorities in a manner similar to arterially drained rivers.

On the left are six people placing timber poles into the riverbank which has eroded away and on the right the same stretch of bank has more vegetation which has filled in the eroded area. Before (2018) and after (2020) of work by the Inishowen Rivers Trust on a bank of the Culdaff River in Co Donegal Inishowen Rivers Trust Inishowen Rivers Trust

Nature-based solutions to erosion include placing a mix of spruce and willow, called a brash revetment, on river banks, where it traps sediment and prevents erosion. The spruces are very densely branched, and this creates a net that traps the sediment, said Murphy. “The willow then regrows and so it brings vegetation back into the bank and helps to hold the structure together as well.”

Working with local landowners, the Trust applied this method to sections of rivers where the bank was being eroded away. The brash “kills the energy” of the river at the point where it is placed, so the river doesn’t erode there anymore. “It helps the river to settle down,” explains Murphy.

In the Glennagannon River, where erosion and flooding were eating away at the river’s bank, nature-based river restoration using brash revetments allowed the bank to regrow and build up over a short space of time. “The farmer is delighted. He has regained the ground he lost and it worked out really well for the river too,” said Murphy.

There are many additional benefits to this method, including creating habitats for fish and macroinvertebrates, and improving water quality.

“Sedimentation is a major issue for many of Ireland’s rivers,” said Murphy. “Excess sediment impacts habitats, such as gravel substrates for spawning fish, and reduces water quality. Some pesticides also bind to the sediment. Removing or trapping suspended sediment from the water column using a brash revetment will provide a range of benefits, she explained.

Trish Murphy wearing a bobble woolly hat and safety glass hunkered down while working in a river. Trish Murphy is advocating for nature-based solutions to erosion Inishowen Rivers Trust Inishowen Rivers Trust

The Inishowen Rivers Trust also works with farmers to develop buffer zones around rivers so runoff from fields doesn’t end up in the rivers, said Murphy.

“We do get a lot of conversations with landowners about vegetation on the rivers, [where they feel] that there’s too much, whereas we feel there is a balance to be reached.”

Making rivers ‘more amenable’

In terms of restoration, the OPW told Noteworthy that it collaborates with IFI on carrying out enhancement works on rivers.

Enhancement works involve putting materials that have been taken out in the original drainage scheme back into the river, said Declan Cooke, National Fisheries Habitat Development Manager with IFI, who assesses rivers that have been damaged by drainage activity, recommending physical solutions and restoration work.

Since the 1990s, IFI have been working on physically repairing channels that have been drained in the ’60s and ’70s to make them more amenable to trout and salmon, he said.

This involves putting structures into the river such as gravel and deflectors “to try to get the river winding and bending the way it used to”, said Cooke.

IFI also advises the OPW on how to minimise disturbance to salmon and trout when works are close to spawning or nursery grounds, or asking that silt curtains be installed to minimise disturbance to fish from sedimentation.

In an email seen by Noteworthy regarding the OPW works due to take place in the River Moy, IFI staff comment: “IFI welcomes lighter touch manual hand works in place of machine work. [...] Minimal disturbance to the riparian zone should be implemented when carrying out machine work.”

Declan Cooke wearing safety gear and wellies, while holding a large stick, walking through a river. Declan Cooke of IFI assesses rivers that have been damaged by drainage activity Inland Fisheries Ireland Inland Fisheries Ireland

Lack of funding to ‘slow the flow’

“We don’t need to prove that these nature-based solutions actually do work. They do,” said Dr Mary Bourke, a geomorphologist at Trinity College Dublin’s Department of Geography.

“But what’s missing at the moment is strategic funding opportunities for local communities and county councils to start adopting them and using them,” added Bourke, who is currently examining the role of nature-based solutions in mitigating floods as part of a project jointly funded by EPA and the OPW.

“We are trialling some nature-based solutions on agricultural land to see if there’s an effective way that we can mitigate all ranges of floods, both the big ones and the small ones,” she said.

This involves “increasing the roughness that the water encounters. You’re slowing it down. Slowing the flow is the mantra. And this is where the practices that the OPW engage in are at odds with what the science is saying is best practice, in that, by removing vegetation, in terms of the hydraulics, the mechanisms of water flow, you’re making it smooth, and we’re trying to make it rough, we’re trying to slow it down.”

River with vegetation and stones near its surface with quote by Dr Mary Bourke, a geomorphologist from Trinity College Dublin - River restoration for a geomorphologist is actually restoring everything: river, floodplain and catchment; the riparian vegetation; it's all of it. Photo - Maria Delaney Photo - Maria Delaney

To flood or not to flood

UCC’s Harrison is part of a team investigating field-scale flood storage, to see whether it is possible to “subsidise farmers at least in winter to retain floodwaters on their land”.

“You get better production from land, if you drain it. And if you drain the land you get less local flooding. The trouble with drainage is that it may benefit the local landowner, but you’re putting water much more quickly down the channel, which is going to increase flooding downstream.

“It’s a well known concept: if you increase the drainage upstream, it is going to increase the discharge, the flood risk downstream. There’s a degree of conflict here between drainage upstream, benefiting individuals because they have better drained land, and greater flood risk to people, villages and towns downstream.”

Holding the water back in the field for about 24 hours, and allowing the water to seep back into the stream over a much longer period, “should reduce the peak discharge downstream and alleviate flooding”, he explained.

“What we’re hoping is that if you then scaled it up, and many, many farmers were doing this kind of thing, it would alleviate flooding downstream. Of course, we’d have to show that there was no damage to the land.”

“No farmer wants their land to flood”

The idea that grants should be put in place for farmland to be allowed to flood was expressed by many sources, but not everyone is convinced.

The details of any proposals around compensating farmers to allow their fields to flood would need to be carefully considered, said Paul O’Brien, chair of the Irish Farmers’ Association (IFA) Environmental and Rural Affairs Committee. “I would be reluctant in the IFA to back such a proposal until I saw what it looked like,” he told Noteworthy.

River with trees overhanging with quote by Paul O’Brien, chair of the IFA Environmental and Rural Affairs Committee - Obviously no farmer wants their land to flood, because if it floods it's detrimental to what can be achieved from that land. Photo - Maria Delaney Photo - Maria Delaney

In Ireland, “there is a long standing problem with maintenance on river banks,” he said. There is a need for some maintenance but there is no single body in charge of river maintenance, he added.

There are “too many different stakeholders involved”, according to O’Brien, and “ultimately, no one is making decisions”.

If a farmer “sees something that potentially is going to pose a problem”, they are unsure who to call, he said. For instance, “if a tree is about to collapse and fall into the river and bring a considerable amount of clay with it, if it was maintained at that stage, it could solve a problem further downstream”.

O’Brien believes there should be “a balanced approach”, whereby maintenance is done
“where you can see a benefit to potentially reduce the chances of a flooding event”.

An Act in need of reform

The majority of sources we spoke to felt strongly that the Arterial Drainage Act needs to be reformed.

“I think the law needs to be changed,” said Bourke of Trinity College Dublin. “But it has to be informed change. [...] It’s the whole approach to managing a section of a river that has to go, it’s no longer best practice at all.”

A small tree growing out of the riverbank which has no other trees along that stretch and little mature vegetation. A lone tree stands beside branches left on the bank of the River Brosna after OPW maintenance works last year Maria Delaney Maria Delaney

The Inishowen Rivers Trust also believes the Act needs to be “revisited and revised, and even repurposed. Instead of pulling up the vegetation and maintaining the process of dredging and clearing, doing work to restore the rivers back to their proper function would help greatly.”

CorribBeo’s O’Cinneide agrees that there needs to be a revision to the act, and that it needs to be updated to take account of “best available practice in ecological screening and appropriate assessment”.

There is also a need for “better guidance and better processes agreed between IFI, EPA and the OPW and the other state bodies so that they do proper assessments. Proper screening, proper assessment and consultation,” he said.

A petition started by the Irish Wildlife Trust (IWT) last year asking for the Arterial Drainage Act to be reformed has gathered over 5,000 signatures. IWT have not yet received any response to the petition from Minister Patrick O’Donovan.

“The Act needs to be rigorously assessed and thoroughly reviewed to see how it aligns with EU law,” said McGoff of An Taisce.

“That legislation was implemented before any of this EU legislation, before we had a biodiversity and a water quality crisis, before there were any significant environmental concerns, and it was implemented to drain agricultural land to make it more viable.

“But they’ll often be draining quite peaty land that by draining it, it’s turning it into a carbon source. So even in terms of climate change this needs to be seriously reassessed. It needs to be brought into the modern age.”

Design for BREAKING THE BANK investigation - Excavator working on a river bank with cones and tape cordoning off the area in the background. There are trees and bushes to the left of the excavator and a river to its right.

This investigation was proposed and funded by readers of Noteworthy, the investigative journalism platform from The Journal, and carried out by Anthea Lacchia. The Noteworthy general fund also covered additional costs.

You can support our work by submitting an idea, funding for a particular proposal or setting up a monthly contribution to our general investigative fund HERE>>

We also have a number of biodiversity-related investigation proposals which you can view here

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