Draining Castle Semple Loch.

Various endeavours have been undertaken to reduce the level of the Castle Semple Loch. Before discussing these it is worth detailing a few vital statistic’s about the Loch.

It was originally 4.3km long before the road to the Roadhead split it into two, the Castle Semple section is now 2.6km long and at its widest 625m. For half of its length it is around 425m wide narrowing substantially towards the outflow. The surface area is 204 acres and the capacity is 137 million gallons.  A bathymetric survey (see below) carried out around

1900 shows the loch is very shallow with an average depth around 3ft with the deepest part reaching 5ft in the middle of the Loch adjacent to the 1^st island (which is virtually gone). The level of Castle Semple loch above sea level is 89.6ft and the Kilbirnie Loch is 100.3ft indicating the natural flow is towards Castle Semple Loch. The bathymetric survey of the Kilbirnie Loch shows it to be much deeper than the Castle Semple Loch (see below.)

The Glengarnock end of Kilbirnie Loch marks the high point or watershed where water will flow in one direction on one side and a different direction on the other. Specifically, the Glengarnock Business Park sits at 35m or 115ft above sea level thereby blocking any south western flow from the Kilbirnie Loch. The River Garnock runs close to this Business Park but is on the south western side of this high point and so runs southwest. At the Lochwinnoch end the outflow (Dubbs Burn) runs North East towards Castle Semple Loch.

The Semples moved their residence from Elliston Castle to a new abode close to the outflow of the Castle Semple Loch in the early 1500’s - Castletoun. Not much is known about this castle. An old map shows it as being 4 stories high and looking not unlike Barr Castle. It is recorded that a wharf was built allowing direct access from the castle to the Loch. This feature may have been built with access to the Peel castle in mind. The primary reason little is known about the castle is MacDowall knocked it down to make way for his mansion deemed more appropriate for his position.

The only time the Semple’s tried to lower the level of the Loch was around 1680. The purpose was to gain more land to secure rent from the crops it would yield.

The second serious attempt to lower the level of the Loch was by Colonel William MacDowall who had purchased the Castle Semple estate from the Semple’s. The village is probably still living with the fallout from the disputes that arose between MacDowall and the heritor’s on the south side of the Loch.

Considering the Loch's original length (Castle Semple Loch + Barr Loch) it effectively cut the Parish of Lochwinnoch in two (see map below). Parishioners from the South side of the loch used boats to cross the water but they also waded across from two points appropriately known as the “wading places”. They were adjacent to where the causeway was built that becomes the road to the Roadhead.

In the early 1730's Colonel MacDowall deepened and widened the Black Cart at the outflow of the Loch. This reduced the level of the loch such that it was no longer navigable and also drained the section which has become known as the Barr Loch. McDowall dug a canal down the centre of the drained Barr Loch section to take the flow of the Dubbs burn. This made the wading place impassable and the last straw was destroying the small wooden bridge at the outflow of the Loch. These actions forced southside parishioners to either cross via the Elliston Bridge a further 900m downstream from the Loch's outflow or the Kerse Bridge near Kilbirnie Loch. The distance between these bridges is approximately 4 miles. To add to the difficulties faced by the southside parishioners MacDowall, who had purchased all the land from the mouth of the Calder to Skippers Path (more on this path later), built two stone dykes further impeding their route to church.

Below is Roy's Military map of 1755 which shows the effect of McDowalls drainage. It also shows other changes that took place between the start of the drainage and 1755 which will be detailed in the following paragraphs.

On 25^th July 1734 the south side heritors raised an action of molestation and declarator against MacDowall. This action took 2 years to wend its way through the Court system but they won.

MacDowall agreed to construct a road and build a bridge to the specification agreed by the Court. The work was to be completed by the end of 1736 but – you guessed it – by 1744 it was still incomplete. The heritors had yet again to go to Court. MacDowall had only given his word that the work would be carried out. The excuse he pled for the work not being completed was that whatever work he did was swept away by the “impetuosity” of the Calder.

Today the flow of the Calder into the Loch is away from the Roadhead road towards Howwood. Back then the Calder entered the Loch on the Kilbirnie side of the Roadhead Road hence why its flow, especially when in spate, could wash away any partially constructed road which it would then be flowing towards (see map below for possible original route of Calder).

The heritors sought Court authority to carry out the work themselves. MacDowall would not agree to this but on 8^th August 1745 he was instructed by the Court to complete the work. Again the work was not carried out and on 27^th Feb 1747 the Court of Session gave the heritors authority to carry out the works.

The embankment allowed by the Court was to be raised six feet above the marshy ground with the breadth at the bottom 14ft and 8ft at the top. The retaining walls were to be formed from sods and turf only. It doesn’t take a engineering degree to realise how flimsy this structure was but that was all the Court would allow due to MacDowalls opposition. Further it was restricted to “horse and foot” meaning no carts were allowed to use it. The Dubbs (locally called the Dibbs) which at that time flowed along the canal MacDowall had built down the centre of the Barr Loch was to be bridged by joist and planks laid upon stone and lime pillars at each end.

It was at this time that the Calder was diverted to the North East to make it flow away from this flimsy road. This work was carried out at the Engine Tees. It has been suggested that French prisoners of war worked on the estate and were involved in this work. Three wharfs were constructed to divert the river, the work was referred to at the time as “in going quays”. The French word for a wharf is “quai” or “jetee”. Engine Tees is a corruption of some or all of “in going quays”, “quai” and “jettee”.

The scottish mining term for drift mine, Ingaun e'e (ingoing eye), was another possible explanation for Engine Tees due to mines in the area. I think the previous explanation more likely as it is specific to the location in question rather than relating to a mine in the general area.

The drainage work was continued by MacDowall's son and in 1774 he spent £3000 (£290,000 in today's money) deepening and turning the Black Cart into a canal for 2 miles from the outflow of the loch. He enlarged the central canal through the Barr Loch and added several lateral drains connecting to it. These works reduced the Castle Semple loch to about 20% of its original size. The 1785 estate map below shows how effective this drainage was. The map also shows the location of the "wading places" and a potential route for the original flow of the River Calder.

To complete this part of the story I will say a few words about the Skippers Path and the Boat House on the north side of the Loch. As its purpose was to take parishioners from the south side of the loch to the old Kirk it is not surprising that it started from the road (East End) on the south side of the old Kirk. It ran in a direct line to the Loch shore near the north east end of the “Ministers Meadow” (see montage below). The line of the path was the boundary between the “Old Factory Park” and “New Factory Park” (see top right image in montage below). This would place the north side quay about one third into the existing marina car park. The montage below has a photograph which has often been cited as the boathouse in question. This is not the case. It is located near to where the existing jetty’s are. It first appears in the 1913 map (below, top left image circled) of Lochwinnoch and it is clearly not on a direct line from the old Kirk to the Loch shore. I do remember as an eight year old during the hard winter of 1963 skating up the slope which formed the remnants of the slipway to this boathouse. Only the initial section of the Skippers path remains.

The third William MacDowall inherited the estate in 1776. By 1788 the industrial revolution was in full swing and MacDowall had built the “Old Mill” at the top of Calder Street. Dams became important to ensure a constant supply of water. Disgruntled mill owners on the Black Cart forced MacDowall to reverse much of what his father and grandfather had done with respect to draining the Castle Semple Loch. To further aid the mill owners MacDowall increased the head and capacity by installing a dam 4ft high at Elliston Bridge. In effect the Loch was returned to its original size (see below) to provide storage capacity for the mills downstream. Before re-flooding the Loch, and as part of this restoration, he built three artificial islands by excavating material from the dried Loch bed. The first island is almost completely gone and the loch on the south side of the third island has silted up so much it is no longer an island. The montage below shows the re-flooded loch and the 1^st and 2^nd islands in their heyday. I have no images of the 3^rd island from 1966, but, in any case, it seems more appropriate to show this “island” as it is now.

The causeway that had been built shortly after 1747 was built when the level of the Loch had been reduced. With the drainage works reversed this meant that in times of heavy rain this road was often under water, sometimes to a depth of 4 or 5 feet. The road has been raised several times as is evident by the copes of the retaining wall being level with the current pavement. The net effect is that the road still floods, albeit not to 4 or 5 ft but enough to make it impassable several times a year.

The following links take you to Bitsize 1 and Bitesize 2 which include exerts from newspaper articles in 1852, 1860 and 1861 all bemoaning the flooding of this road. It is reported that the water is over 3ft deep and reaches the top of the wall. They plead for the road to be raised. Incomprehensibly the road has been raised to just below the copes (not even the height of the wall and now it only floods to a depth of 1-1.5 ft! Well that is some progress I guess.

In 1800 James Adam proposed two plans to MacDowall, one to completely drain Castle Semple Loch and Barr Loch and a second to only drain the Barr Loch. The first never happened due to the need for water to power the cotton mills. The second comprised two parts, firstly to enclose the Barr Loch in an embankment to keep out water from the burns that fed into it. The second part was to deal with any natural springs inside the enclosed area and the rain water that might otherwise accumulate. MacDowall built the embankment but did nothing to deal with the other sources of water. James Adam undertook to complete this work in 1813 by buying the whole of Barr Loch and about 100 acres of the south west end of Castle Semple Loch.

The first objective was to improve the embankments already made. The Dubbs burn, flowing from Kilbirnie Loch, had been diverted into a canal 28ft wide on the south side of Barr Loch. The excavated material was clay and this formed the embankment which was 36ft wide at the base and 10-12ft wide at the top. The embankment’s height had to be raised and material for this was obtained by digging a trench on the Loch side of the embankment. As a result of this work the top of the embankment was increased to around 18ft wide.

The north side embankment lay on material with a sandy texture. The lack of clay meant there were many areas of water seepage. In these areas the embankment was opened up to the base and a puddle-bank of clay inserted – 3ft at the base and 2ft at the top.

To drain rain water falling within the embankment and take away any water from natural springs proved very difficult due to the lack of height difference between the Barr Loch and the River Cart near the Loch outflow. To gain sufficient fall the drain was started downstream from the dam at Elliston Bridge. A trench 6ft wide was cut to the depth of the river bed, 25ft from the river bank. This was lined on either side with stone to a thickness of 18in and a height of 4ft. This was then arched over resulting in a drain 3ft wide and 5ft high (due to the arched roof). In total this drain was about 12ft below ground level. This work progressed in sections 5-6yds long with the excavated material back-filling on the last formed arch. The section from the loch outflow to level with the second island required a puddle bed 8ft wide and 2ft deep over the drain to protect it when the loch occasionally flooded this land. The end of this section marked the point where the drain ceased to be covered over. Every 80yds along the covered section vertical shafts were constructed to allow access for cleaning of the drain.

The open section of drain was 5ft wide at the base with sides cut at 45 degrees. At the point where the drain reached the Aird Meadow a self-acting sluice was installed. This was in effect a one-way valve. In the event of the embankment forming the drain along the south side of the loch failing and the water on the downside of the sluice rising above the level of the water on the upside, the sluice would close preventing water re-entering the Barr Loch. The drain followed a line around the Aird Meadow passing the Peel Castle. From the Peel Castle to the road the drain had to be cut a considerable distance from the embankment. It was found that unless this was done the ground was so soft the weight of the embankment pressed out the ground between drain and embankment filling the drain and lowering the embankment! The end of this drain connects via a tunnel under the road to the canals within the embankment surrounding the Barr Loch. The canals encircling the Barr Loch embankment feed directly into the Castle Semple Loch, the north side flowing under the Loch Bridge and the other (which takes the water of the Dubbs burn), locally called the Dibbs, flows under the Lochall Bridge. The Barr Loch or Barr Meadow was usually referred to as the "Meeda".

The drain running through the centre of the Barr Loch was deepened and multiple side drains installed. The centre drain is 20ft wide at the top and 14ft at its base. The side drains are 18ins wide at their base with sides cut at 45 degrees making them roughly 5ft wide at the top. At the head of the central drain is a sluice. By opening it and closing the sluice at the other end the entire enclosed area can flooded – a process known as warping. The idea is by allowing flood water onto the land it will deposit a rich fertile silt improving the productivity of the land. This was done for the 3^rd Grand Curling match held on 11^th Jan 1850 for the purpose of creating a curling rink when Mrs Elizabeth Harvey had a Court issue a suspension and interdict to prevent trespass, curling, skating or sliding on Castle Semple loch!!! MacDowall of Garthland agreed to flood Barr Meadow to a depth of 2-3 ft. There were 1100 competitor and upwards of 11,000 spectators for the match.

A catch water drain ran along the length of the south side of the Aird Meadow and Castle Semple Loch.  This collected surface run off preventing it from entering the open drain.

The vital statistics for this drainage scheme are as follows:

Covered drain – 1752 yds

Open drain – 2541 yds

Catch water drain – 2590 yds

Central drain in Barr Loch – 1776 yds

Side drains in Barr Loch – 5673 yds

Drain and bank around Barr Loch – 4563 yds

Below is James Adams sketch of the scheme which was completed in 1814 with some additional finishings and repairs in 1815 at a cost of nearly £7000.

Between the Barr Loch and Aird Meadow some 230 acres of farming land was recovered – 169 from the Barr Loch and 48 from the Aird Meadow. The remaining acreage is taken up by the drains and roads. The drained Barr Loch was ploughed and planted with oats in 1816, 17 and 18. Following this about 60 acres was set aside for hay. In 1826 the crop of oats and hay from the Barr Loch realised a profit of £1533, and the Aird Meadow generated £263 profit. In 1827 the respective figures were £863 and £165. Adam took the average of these two years of income (£1413) and subtracted £36 from this as the average income from these area’s prior to being drained to arrive at the level of improved rental due to the works ie £1377. Taking the cost of the works as £10,000 he equated the improvements due to drainage as producing a 13.8% return on investment.

James Adam sold the Barr lands back to MacDowall in 1820 (just to be clear this was now the 4^th MacDowall), he was the nephew of William MacDowall III. The MacDowall’s remained prominent in the area till they sold Garthland in 1935 to the Millhouse Missionaries. The Barr Loch and Aird Meadow remained dry, except during very heavy rainfall, for the next 126 years when it flooded in 1946 and never drained again.

MacDowall added a pumphouse to help remove water from within the embankment surrounding what had been the Barr Loch. This extracted water from the drainage system within the embankment and fed it into the canal around the outside of the embankment. Although the drainage system within the embanked area was quite a feat of engineering it did suffer from having a small fall between the Barr Loch and the outflow at Elliston Bridge. This pump was installed sometime between 1820 and 1855. Initially it was driven by a waterwheel but latterly it was a steam engine. The location and ruin of this pumphouse is shown below. When it ceased to operate is unknown but probably sometime after MacDowall sold the estate in 1935.

In the vicinity of the Loch Bridge is the Cowp, Pat recollects hearing a regular thump, thump, thump from what he took to be a pump. In the late 1960’s a company of Royal Engineers (RE) “took up residence” in the cowp for a few weeks. Apparently to do work on the drainage system / pump. Where this pump was, why RE’s were involved I know not. I do remember they used to share the cakes they got in their rations which were very nice. For clarity the cowp is a small piece of land going out from the Loch Bridge into the Barr Loch. It is where the Council used to dump all the rubbish collected from Lochwinnoch.

All of the works described in this article are slowly disappearing with the ravages of time compounded by repeated flooding and the land being left to look after itself. Below are a series of photographs of the present day condition of some of the infrastructure covered in this article.

Loch Bridge which was upgraded by Keanie in 1900 and widened by 10ft.

Looking towards Barr Loch and the Cowp from Loch Bridge. Hard to imagine there used to be a road big enough for bin lorries to get out to this "island". North side drainage canal off to right.

Lochall Bridge with the Dibbs flowing underneath it.

Looking from the Lochall Bridge along the Dibbs canal that goes round the south side of the Barr Loch embankment.

Canal that goes round the north side of the Barr Loch embankment. Neglected and heavily overgrown

Walking digger clearing the Dibbs burn in October 1978

Job well done - didn't stay that way for long