Fourteen troughs on the same supply, at the same pressure, in the same weather. Thirteen ice up and get broken every morning from December. The one on the top, in the wind, has never had ice on it in thirty one years.
I farm four hundred acres of hill ground and I have fourteen troughs on it.
They are all the same: a concrete trough with a ballcock in a box, fed from a header tank up at the top of the ground, gravity down. Same make, same size, same age near enough, because they went in over about four years in the eighties.
From about the middle of December I break ice every morning. That is the winter job nobody photographs. You go round with a bar, you break the lid on each one, you clear the pieces out so it does not re-form thicker, and you check the ballcock has not frozen open.
It takes an hour and a half and I have done it for thirty one years.
Trough 11 has never had ice on it.
It is the highest one, at about four hundred and twenty metres, on the shoulder where the wind comes across from the west with nothing between it and the sea.
It is the trough that ought to be the worst. It is exposed on all four sides, there is no wall near it, and the pipe run to it is the longest on the farm.
The water in it is not warm.
I want to say that first because it is the thing anybody asks.
I have put a thermometer in every trough on this hill on the same morning, more than once, and the water in trough 11 is between one and two degrees, which is what water is when it is about to freeze and has not.
It is the same as the others. The others have four inches of ice on them and the same temperature underneath.
The obvious answers, and I have been round them for a long time.
Moving water does not freeze as readily. A trough with a slow leak is a trough that stays open.
Trough 11 does not leak. The ballcock is sound and the level is steady, and I have watched it for an hour with a mark on the concrete.
A spring under it. This is the country answer and it is a good one, because water out of the ground is at eight or nine degrees all year and it is why some troughs on some farms never ice.
There is no spring. The trough is fed from the same header tank as everything else, through the same blue pipe, and I know that because I laid two hundred metres of it in 1994 myself.
And a spring fed trough is warm. Mine is at one and a half.
What I have measured, which took me until about 2015 to think of.
The concrete.
The trough itself is at about the same temperature as the water. What is different is the ground round the base.
I have a probe thermometer for silage and I have put it into the soil at eight troughs on the same morning, six inches down, a foot out from the concrete.
Round the others it reads what the ground reads on a hill in January, which is a degree or so either side of zero.
Round trough 11 it reads five and a half.
Five and a half degrees in the ground on a shoulder at four hundred and twenty metres in January is not possible and I have said so to two people.
The first was the man who does my water, who said it must be a leak from the pipe warming the ground, and I said the pipe carries the same water as everywhere else at one and a half degrees, and he thought about it and said that was a fair point.
The second was a hydrologist I got hold of through the union, on the phone, for twenty minutes. She asked about the geology, which is gritstone, and about mine workings, which is the sensible question because old workings can vent air, and there are none within four miles and I have the plans.
She said she could not account for it and that if I ever wanted it looked at properly she would come, and I said I would think about it, and that was in 2019.
The extent of it.
I have probed out from the trough on a grid, on three separate mornings, because once you have a probe and a cold morning you may as well.
It is a circle. About eleven metres across, centred a little to the north of the trough rather than on it, and the edge of it is sharp: five metres out it is five degrees, six metres out it is zero.
The grass in that circle is not different in summer. I have looked hard and there is nothing to see, no growth ring, no colour, nothing that shows in a dry spell.
In winter the snow lies on it the same as everywhere else. That is the part I find hardest, because ground at five and a half degrees should take the snow off it, and it does not.
What I do about it.
I do not break ice on trough 11, because there is none, and that saves me four minutes of an hour and a half.
The stock use it. They use it more than any other trough on the farm in the winter, which is what animals do when there is one open trough and thirteen frozen ones, and it is the reason I have never fenced it off.
I have thought about that a good deal. There is nothing wrong with the water: it has been tested twice, for the assurance scheme, and it comes back the same as the mains.
What I have stopped doing is going up there in the dark.
I used to start the round at the top and work down, because you finish near the house and the last trough is the one by the yard. Now I start at the bottom and finish at eleven, in the light, and I stand about there for a minute afterwards, and then I go home.