The (Portlaw) Clodiagh

This article was written in 2002: circumstances on the Clodiagh may have changed since then. I have added some photos and some extra information about the lock.

Update: on 7 April 2010 two kayakers were drowned at a weir on the Clodiagh at Portlaw. Story here. May 2011: the official report on the drowning is on the Marine Casualty Investigation Board website.

Update October 2010: added two 1985 Chris Allen photos, the waterwheel pits and the engine house, under a Creative Commons Licence.

Update April 2011: Portlaw Heritage Trail set up.

Update August 2011: link to Portlaw Heritage Centre blog. 

Update March 2017: an ad from 1785 about flour mills at Portlaw and water transport to Waterford by three rivers: the Clodiagh, the Suir and St John’s Pill.

The compilers of the Euromapping Irish waterways map didn’t miss much. Their map shows, for example, the Bride, the Castlemaine, the former Bridgetown Canal and the position of the tiny Broharris, none of them amongst the most-used waterways today. But the map doesn’t show the Clodiagh, a tributary of the Suir.

The town that stands on the Clodiagh is shown: Portlaw, about two thirds of the way upriver from Waterford to Carrick-on-Suir. If you’re on the N24 Limerick to Waterford road, and you want to go to somewhere on the Cork side of Waterford city, you can cross the Suir at Carrick or at Fiddown and follow a minor road to the south of the river. The surface is surprisingly good: it was improved for the Tour de France some years ago. But there is one hump-backed bridge, about half way between Fiddown and Kilmeaden, and it crosses the Clodiagh, a river that was crucial to one of the most extraordinary industrial empires of the south of Ireland. Turn westward off the road and you’ll find yourself in Portlaw.

The road-bridge at Portlaw

The road-bridge at Portlaw


There is no towpath under the bridge.

The River Clodiagh to the left, the canal to the right

The River Clodiagh to the left, the canal to the right

Portlaw’s beginnings

Portlaw is a small town in Co Waterford, on the river Clodiagh, a tributary of the Suir. It was developed in the nineteenth century by the Quaker Malcolmson family, and may be the only planned industrial town in the republic of Ireland. At its peak, it had over 4,000 inhabitants and, by 1844, over 1,800 people worked at the plant.

David Malcolmson, born in Lurgan in 1765, came to Clonmel in 1784 to work for Sarah Grubb at the Anner Mills. After some years, during which he held a number of different jobs, he went into the milling trade with his brother John; they also had an interest in the coal trade and boat-building.

According to Desmond G Neill

In 1819 he brought three of his sons, Joseph, Joshua and John into partnership in the firm, now named David Malcolmson & Sons.

In 1822 the Malcolmsons leased a mill at Pouldrew, which brought their operations further down the Suir, nearer Waterford. They decided to diversify, and in 1825 they built a cotton mill nearby at Mayfield, Portlaw, where there was a disused ironworks and where the river had been made navigable for barges of 20 tons. Five storeys of the original seven-storey cotton mill remain today.

The main building at Portlaw

The main building at Portlaw


The importance of water

It was the Clodiagh that first attracted the Malcolmsons to Portlaw. Central to the operation was sophisticated use of the waters of the Clodiagh. A weir, with a fish-pass, diverted water to power three 30′ water-wheels and to provide water for the town and the mill: according to Bill Irish

Water was diverted with ingenuity from a sluice on the river through the millpond, and underground culverts directed it into a huge water-wheel which provided the motive power for the pumping plant. From the plant, water was pumped through pipes uphill for half a mile to a small pond 153ft above the factory roof, which gave a magnificent gravitational fall to feed the factory operations, the fire hydrant reservoir in the mill parapet, and freshwater pumps in the village.
Where the Clodiagh joins the Suir

Where the Clodiagh joins the Suir


Chris Allen took some good photos in 1985 and licensed them for re-use under the Creative Commons Licence. Here is one of the waterwheel pits:

Two waterwheels were sited here and drove the original cotton factory. © Copyright Chris Allen (1985) and licensed for reuse under the Creative Commons Licence


Here is the other, showing the engine house:

The engine house contained two rare Robey stationary steam engines: a uniflow and a side by side compound. © Copyright Chris Allen (1985) and licensed for reuse under the Creative Commons Licence

Water that had passed the water-wheels fed a half-mile stretch of canal, which rejoined the Clodiagh downstream and was used to carry goods to and from the mill. The canal ran under the factory receiving-house and (according to Bill Irish) it “intensified the fall in the head-race”. He says:

For the cotton factory alone over 60 seagoing vessels of 100–150 tons and 150 open boats of 30–40 tons made passage between Waterford and Portlaw annually.

He suggests that John Skipton Mulvaney or William Dargan may have designed the canal system. The canal is navigable, at least by small boats, up to the village.

The lock at Portlaw

The remains of the only lock on the canal can be seen at what is probably a horse-bridge, just downstream of the town bridge.

Horse bridge with supports for lock gate

Horse bridge with supports for lock gate

The lock had a single pair of gates. The Clodiagh is tidal up to Portlaw. It seems likely that, when the incoming tide made a level with the water above the lock, the gates would open, but a falling tide would close the gates automatically. Enquiries amongst well-informed waterways enthusiasts have found no similar lock elsewhere in Britain or Ireland, although a similar principle may be used on coastal sluices. I would be glad to hear from anyone who can provide more information or explanation.

In plan, the gates are triangles with rectangles on the end, with the apex of the triangle at the bridge end and the rectangle attached to the third, short, side remote from the bridge. The gates fit into brick recesses when the lock is open.

Gate recess

Gate recess

The gates have metal supports but wooden structures with wooden faces. All three sides would have been acted upon by the water: one opposing the incoming flow and two the outgoing. This sketch was given to me by the late Mike Stevens; the curve shows the bridge:

How the gates may have worked

How the gates may have worked


Gate support

Gate support

The  weight of the gate is taken by the vertical metal post at the bridge, which has tie-bars through it transferring the load.




A gate from the far side

A gate from the far side


The Malcolmsons were also involved in the River Suir Navigation Company, which enabled 300-ton vessels to reach Carrick-on-Suir, with teams of twelve horses pulling pairs of flatboats further upstream to Clonmel.

The weaving shed and a chimney

The weaving shed and a chimney

Portlaw: planned town

The Malcolmsons built several streets of houses for their workers, many of which still have their distinctive round roofs, which were covered with tarred calico. The calico was produced at the mill and the tar was a byproduct of the firm’s gas works, the town being one of the first with gas public lighting. These roofs were later copied in Belfast and on the Ruhr.

Portlaw roofs

Portlaw roofs


Shops in Portlaw

Shops in Portlaw


A street in Portlaw

A street in Portlaw

The Malcolmsons provided a school, with seven teachers at its peak (and with Bible-based but non-sectarian education), a hospital, shops (with lower prices than those in the surrounding areas), a bakery, a Provident Society, a Tontine Club, evening classes, a Literary Society, a Philharmonic Society ….

The courthouse/school

The courthouse/school

The Portlaw planned town may have influenced the design of Bessbrook in Co Armagh, which in turn influenced George Cadbury’s plans for Bournville and Titus Salt’s model village of Saltaire. Portlaw is thus extremely important, not just to Ireland but to all of these islands.

The Malcolmson empire

The Malcolmsons also owned the Neptune ship-building yard in Waterford, where the Phoenix was built. As well as the River Suir Navigation Co, they were involved with the Waterford Commercial Steam Navigation Co, the Cork Steam Ship Company, the London–St Petersburg Line, the London and Limerick Steamship Company and others. Bill Irish says that by 1858 they had 70 ships registered in Waterford, with interests in many others elsewhere.

The Phoenix on Lough Derg in 2008

The Phoenix on Lough Derg in 2008

Joseph Malcolmson (of the second generation) was a director of the National Irish Bank and a shareholder in several railways and in coalmines on the Ruhr. In Portlaw, operations expanded from spinning and weaving to include bleaching, dyeing and printing.

But Joseph died in 1858 and his widow withdrew her share of the capital from what had remained a partnership, by then called Malcolmson Brothers. He was the oldest brother, and the next oldest two, Joshua and John, were involved in the business, as their father David had intended. There were three younger brothers, whom David had expected to “strike out on their own with capital provided for them”, as Bill Irish puts it. But when Joseph died, only fourteen years after his father, William, the fifth brother, took over as senior partner.

Under William’s stewardship the business suffered one setback after another. There were unwise investments — the Lax Weir in Limerick, a turf briquette factory in Castleconnell, the Limerick–Castleconnell railway and its extension to a pier at Killaloe — some of which were William’s private investments, outside the partnership. He was involved in the Galway Line, seeking to provide a transatlantic mail service, and the partnership ran the London–New York Line.

Footbridge over former railway line to Killaloe (Ballina)

Footbridge over former railway line to Killaloe (Ballina)

Then the American Civil War hit the cotton business, the foundation of it all. Malcolmsons’ bankers went bankrupt, with £2,000,000 of Malcolmsons’ money. John, one of the three older brothers, withdrew his capital. Joseph’s son David, one of the partners, died, and his widow withdrew their son’s capital. According to Desmond G Neill, that son died at the age of 20 after working as a fisherman in Dunmore East.

The tannery

The Malcolmsons’ firm collapsed in 1877. The Portlaw Spinning Company took over the mill, but it failed in 1897. By 1910 the town was desolate, but in 1934 it entered its second period of growth. Portlaw, in other words, was at the centre of not just one but two remarkable Irish industries, in two successive centuries, and the site has buildings from both eras.

Irish Tanners Ltd took over the site and built a tannery that, at one stage, was the largest in Europe, employing 600 people. The tannery too used the Clodiagh’s water, this time for treating the hides. Tanning was a seven-day process, with the hides suspended in pits on chains or spikes, and shaken every day. There are still traces of the bogeys used to move the hides around the yard. Sand was brought up the canal in the tannery days.

Inside the tannery

Inside the tannery

Argentina could ship leather to Britain at the same price as Portlaw could buy in untreated hides, so Portlaw had to concentrate on fine leather, including wet-look leather. Some of the company’s customers preferred leather from Portlaw to that from the other tanneries in the group; it was suggested that something in the quality of the Clodiagh’s water made it particularly suitable for treating hides.

The tannery was closed in 1985, although it had two years’ orders at the time, and some employees moved to other plants in the group at Carrick-on-Suir, Gorey and Dungarvan. Mayfield House, the principal Malcolmson residence on the site, was used as offices by the tannery and for about ten years afterwards, but is now a ruin.

Mayfield House

Mayfield House



The gate-lodge: entrance to the mill on the left, to Mayfield House on the right

The gate-lodge: entrance to the mill on the left, to Mayfield House on the right


The entrance to the mill is on the left, that to Mayfield House on the right

Wheel used to open the gates

Wheel used to open the gates


The former Mill Pond of 3.65 acres, and an extension of 0.69 acres, were filled with waste during the tannery years, and in 1995 the Environmental Protection Agency (EPA) found all sorts of chemical nasties in it. EPA sampling points on the river and canal at the town bridge showed decreased pollution after the tannery closed, but the landfill site is probably still contaminated, and it is known that other chemicals were used or stored on the site.

Portlaw today

In describing somewhere like Portlaw, it is all too easy to think of it solely in terms of its past, forgetting that people still live there today. But if the Portlaw National School’s website is anything to go by, the town did not go to sleep when the tannery closed.

Many schools have websites and a surprising number are of waterways interest, but this is one of the best, with both a solid core of historical material and much modern news and information about Portlaw. The school’s pupils and staff, and in particular whoever manages the website, are to be congratulated.

According to the Munster Express (03/08/01), Waterford County Council appreciates the value of the Clodiagh navigation:

The unique planned industrial town of Portlaw is to benefit from the re-opening of the canal bank walk overlooking the Clodiagh River. The existing stairway to the canal bank is to be repaired and restored to create a walkway and viewing area. The plan includes the planting of a wildflower meadow and the lowering of the stone wall along Bridge Street to open up views to the surrounding hills.

The Council planned to spend £100,000 on the project.

Visiting the town today, you can see the bridge, canal and (downstream) what may be the remains of the lock: one pair of gates forming a sharp V. The mill and tannery are on private property, although the entrance, with its lodge and wheel-operated gates, is visible. In fact the past is all around in Portlaw, from the layout of the streets to the remarkable roofs.

The threat to the weir

This section has not been updated since 2002.

But in a sense the most important aspect of Portlaw, the basis of the Malcolmsons’ operation, is the water power of the Clodiagh, diverted to the mill complex by the weir at the upriver end of the complex. That weir supplied the canal, the water-wheels, the factory and tannery and the town. And it is now under threat.

The Clodiagh below the weir

The Clodiagh below the weir

At present, the weir has no sluice-gates and the water gushes out into the Clodiagh. It is said that salmon are unable to swim against it, which is scarcely surprising. However, when the gates were working, excess water went over the weir to the river, and it is said that salmon were able to leap up it. There is also a fish-pass.

But the weir needs somebody to look after it: to clear debris, open and close the gates from time to time, perhaps — the Department of the Marine suggests — even to deter poachers from time to time. The weir itself also needs some repair.

The Southern Regional Fisheries Board, supported by the Department of the Marine, proposes to construct a “River By-pass channel to facilitate migratory fish passage”, to allow salmon to travel upstream. This bypass would be upstream of the weir; it would cause the channel and weir below the diversion point to dry out in average flow, although the channel would fill, and, flow over the weir, in flood conditions. No water would enter the tailrace except in high floods; it would continue to receive water by seepage from the river and by “tidal intrusion”. The Board suggests that, if necessary, a pipe could take a gravity feed from the river below the weir to the tailrace; alternatively, a small piped supply could be fed from above the diversion to the headrace, allowing intermittent operation of a demonstration millwheel.

The owner of the site is opposed to this, and fears that the canal might be permanently deprived of water instead of being restored. The SRFB got planning permission; a local Fine Gael councillor, Paudie Coffey, and the Heritage Council, have submitted objections to An Bord Pleanála. The Heritage Council has also been a partner in preparing a conservation plan for Portlaw (expected soon).

Cllr Coffey says that the weir bypass will jeopardise part of Portlaw’s unique heritage and seriously affect the canal and mill race, which are both listed as protected structures under the Local Government Act 1999. He is quoted as saying “The canal and the mill have a deeprooted affinity and attachment with the community.”

The marquis of Waterford was quoted in The Irish Times as condemning the submission of objections, saying that salmon are more important than industrial heritage. The account in The Irish Times did not say anything about the ownership of the salmon fishing rights. I have spoken to the Marquis, who confirms that he owns them. He says that he is acting in the national interest.


Salmon are important, yes, but Portlaw is unique. Removing its fons et origo, its water supply, the reason for the development of this extraordinary town, would be a very serious step. This is surely one of the richest industrial heritage sites in Ireland, and one with a strong waterways connection; it is surely worthwhile seeking alternatives to the drying out of the weir.


Tom Hunt Portlaw, County Waterford 1825–1876: Portrait of an Industrial Village and its Cotton Industry, Maynooth Studies in Irish Local History Number 33, Irish Academic Press, 2000, 0-7165-2722-7

Desmond G Neill Portlaw: A Nineteenth Century Quaker Enterprise Based on a Model Village, Historical Committee of the Religious Society of Friends in Ireland, 1992, 0-9519870-2-X

Bill Irish Shipbuilding in Waterford 1820–1882: A historical, technical and pictorial study, Wordwell, 2001, 1-869857-50-X

History section of the website of Portlaw National School

Site visit, arranged by Rosaleen Miller of IWAI Heritage & Conservation Committee, and discussions with Victor Bowers and Mikey O’Shea

Documents supplied by Waterford County Council

Telephone conversations with Cllr Paudie Coffey and the Marquis of Waterford


15 responses to “The (Portlaw) Clodiagh

  1. Kathleen Crotty

    This is a brilliant piece of research. What a pity that it is overshadowed by the tragedy which occurred at the weir on April 7th
    Kathleen Crotty
    PRO Portlaw Heritage Centre

  2. Kathleen: thanks for that. I must admit I didn’t know that anyone canoed or kayaked upriver of Portlaw so I never imagined a double drowning in those circumstances. bjg

  3. it has to take 2 deaths for the department to realise their mistake when they changed the course of the river!!!Again the simple people suffer!

  4. patricia mcavinue

    Thoroughly informative and entertaining . I really enjoued this and learnt a lot too.

  5. Thanks, Patricia. bjg

  6. I am coming to Portlaw in July this year 2011.I will be bringing someone who was born there.Her name was Margaret Maher,She lived in William Street with Her Brother William and Sister Mary Rose.Both ladies are still alive but We’re not sure of the Brother.We are trying to trace William to see if He is still alive(reunion?)If anybody has any info that would help,could You e.mail Me.Also any friends that would like to see Margaret and Her niece Donna.Many thanks hope to here something soon. Jon

  7. I have replied directly to Jon. bjg

  8. Congratulations on well-researched and documented journey through Irish
    industrial, and moreover European industrial history.
    I have been researching the Malcomson contribution to German industrial
    history for some years now while at the same time following Irish efforts, mainly at local level, to inform and plead for conservation.
    Might I suggest that the accounable author make contact wit me, with a viewto stating the case at international level. Given the current economic situation at your end and given Germany’s role in Irelands future, I feel the time is right to return the compliment i.e Malcomson Investment in Germany’s Ruhr valley and the growth of North Rheine Westphalia as Germany’s industrial hub. I am based in its Capital – Düsseldorf on The Rhine – look forward to a concerted action! Sincerely, Maryan Tarpey.

  9. Pingback: Deaths at Portlaw | Irish waterways history

  10. With regard to your description of what I interpret as a set of tidal doors, I illustrate something similar at Battlesbridge in Essex here

  11. That’s very interesting, Robert. How far does the water extend above the gates/doors? bjg

  12. William philip Malcomson

    I really enjoyed reading this, thank you very much
    W.Philip Malcomson
    (Great grandson of the William M mentioned in your account)

  13. Thank you. Your family’s business was a most remarkable one. bjg

  14. The Malcomsons were years ahead of anyone around that time

  15. Pingback: A Bourne mystery | Irish waterways history

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