Burgh Loch - Hidden Water

It was lockdown and there was no river to walk to within the allowed radius of our front door. My walks were confined to the Meadows Park in Edinburgh and Bruntsfield Links. Middle Meadow Walk, the main art of the Meadows was once the Burgh Loch, which was part of the historic old Burgh Muir and one of the main water supplies for Edinburgh’s Old Town. Over a period of 200 years, the Burgh Loch was drained sporadically, and today there is no sign of a Loch being part of the Meadows. It is only during long periods of rain, that the water in the lower portion of Middle Meadow Walk begins to pond. The Bruntsfield Links was once a moor with oaks and Scottish nobility used the grounds for hunting. During the 16th Century stone quarries were dug, in such a way as not to interfere with the local recreation of golf. The deep depressions in Bruntsfield Links today are the remnants of these stone quarries dating back to the 16th Century (1).

I was curious about how these depressions created differences to the growth of grass, particularly during the summer. The grass remained greener in the depressions during the summer months, while above the depressions the grass turned brown. There was no visual sign of water, but it was the greener vegetation that reflected the presence of water. The signs of vegetation have been used to find water in dry places for millennia and have been used for centuries to find groundwater. An example of this was in 1927, where the US Geological Survey created a list of plants that were known to extend their roots to the water table, which was not visible above ground - these plants were known as groundwater indicators (2).

“Ten of the 12 water companies in the UK have admitted they are still using the practice of water dowsing despite the lack of scientific evidence for its effectiveness. The disclosure has prompted calls for the regulator to stop companies passing the cost of a discredited medieval practice on to their customers. Ofwat said, “Any firm failing to meet its commitments to customers faced a financial penalty.” (3).

This “discovery” was made by the science blogger Sally Le Page, after her parents reported seeing an engineer from Severn Trent “walking around holding two bent tent pegs to locate a pipe” near their home in Stratford-upon-Avon. Rather than experiencing herself dowsing, or meeting with people who work in the field with finding water pipes, Le Page searched the internet for information about water dowsing, she compares it to a Ouiji board, which she has experienced and then scientific papers to prove whether it works or not. The scientific papers show that based on the expected probability of finding water 95% of the time. This criterion was not achieved and therefore according to scientific evidence dowsing does not work. Following this report, a series of Guardian Readers sent in comments, defending dowsing to detect water. The majority of comments were actual narratives of people who had either dowsed for water or had dowsers who came to their land and successfully found water.

 From my own experience being a soil scientist for many years, there are few scientific methods to “show” what is below ground. The only way to be 95% sure there is water below, is by digging a hole and revealing what is below. This of course is a very time consuming and destructive method. I have dug many holes in my life to find what is “below”, with also the aim to insert water monitoring equipment or measuring infiltration rates. After many years doing this, I very much use an intuitive approach to decide where to dig and I know from my own experience, anyone who spends their time looking for leaking pipes will use an approach that works. So, I am not surprised that water companies use dowsing. It’s about getting a job done, and if dowsing aids in the process, it is better to be used. If dowsing did not work, it would otherwise have disappeared long ago.

My first introduction to dowsing was during my final year studying environmental science. We were on field trip visiting an environmental consultancy . A lot of their work was to find electrical wires that went through dikes for local authorities and private companies. To find the electrical wires they used dowsing rods and a manufactured tool called a radio detection CAT Cable avoidance tool. There were three people working as a team and when asked which tool they preferred, they all said the dowsing rods were the best to locate the cables, and then the CAT cable detector was used as scientific evidence to find the cables. However, the CAT cable detector only really worked if there was voltage going through the cables, whereas the dowsing rods could still find cables without voltage. They explained how they used both tools. Out of a class of 17 students, half of us could find cables that were located under paving stones, the rest of the students felt the dowsing rods never did anything for them. The CAT cable detector only responded to the cables if they were directly over the wires, whereas the rods for me seemed to respond before reaching the wires and then crossed directly above the wires. The experience was something I never really forgot, as to me the dowsing rods were more of a mystery. Why would they react to cables? Was it the human being that was reacting? And the dowsing rods the “indicator” tool?

I decided to try for myself to look for the Burgh Loch. Did it still exist?

My dowsing rods indicated that the Burgh Loch was still there below ground in Middle Meadow Walk, but it disappeared towards Melville drive. When the rods came near to water they began to cross and then when I moved above water they totally crossed to the point that they touched my hands. I also was able to tell where the drains underground were. However, I could not say how deep the water was underground and I had no evidence that there was water underground, because it was not possible to start digging in the Meadows. As I spent time dowsing in the Meadows over a number of weeks, I noticed that after a period of heavy rainfall in August, the dowsing rods showed that the water underground spread outwards towards higher ground. I was surprised that the dowsing rods would indicate such a change. I did find out about the history of where the Burgh Loch had been located, and this did correspond to where the divining rods suggested water to be.

The whole process made me wonder about the human senses. What do we really know about the human senses? What moves the dowsing rods, is it my muscles or my mind, or both? Is it possible that my own body, because I am comprised of water, amplifis a signal of water from underground? I had no way of finding out whether the edges of my crossing rods were really the edges of the Burgh Loch and of course it was subjective line, because the water table would exist at depth, but if I was sensing water with the dowsing rods, it was impossible to know at what depth I was sensing if it was water at all.

When things are hidden, there is always an element of doubt. It is only in revealing what is hidden that we may believe that it really exists. There is also something about doubting the human senses. If there was a machine that said there was water underground, it seems, as suggested by Sally Le Page’s blog and the Guardian News, that we are far more likely to believe the machine and would be happy to pay out taxes for it, than the experience of the hydrologist who works with water every day. Why is the experience of the hydrologist not accounted for, when they are working with water? Why not allow the hydrologist to find the leaking pipe with the methods they find most useful?

References:

1.Edinburgh City Council (2019) The Meadows and Bruntsfield Links Management Plan (2019 - 2024) http://www.fombl.org.uk/otherpapers/Meadows%20Bruntsfield%20Links%20Management%20Plan%202019-2024.pdf Accessed: July 2022.

2. Meinzer, O.E. (1927). Plants as indicators of Groundwater. Water Supply Paper 577. Department of the Interior, U.S. Geological Survey. United States, Government Printing Office, Washington.

3. Weaver, M. (2017) UK water firms admit using divining rods to find leaks and pipes. Guardian News. https://www.theguardian.com/business/2017/nov/21/uk-water-firms-admit-using-divining-rods-to-find-leaks-and-pipes Accessed: October 2019.