This weekend gone we had heavy rain and thunderstorms on Friday night, with almost 6mm of rain falling over the course of the late afternoon and evening - about normal for this time of the year. We'd been on Alerte Orange so had made a few preparations in the garden, moving trays of seedlings under cover and the like. The next morning all was well, the ground had enjoyed its drink and the pond was nicely topped up. The weather was set fair for the rest of the weekend.
Sunday night the heavens opened again, with thunder banging and crashing around - no warning on the meteo and certainly no Alertes in place. We had 65mm of rain, or two month's worth, in just three downpours each lasting little more than thirty minutes. By 3am the roar of water in the fosse, the field drain along one side of our plot made sleep impossible. I tried not to worry about the cat, who insists on being outside at night, or the fate of the vegetable garden, just starting to produce tomatoes and courgettes and with the fist melons forming.
In the morning it took my partner an extra twenty minutes to get out to where he was working as he had to keep stopping to clear, or just slowly drive around rocks, mud and branches all over the road that winds up through the valley forests and onto the plateau above us. The cat arrived for his breakfast with only his paws a little damp and then slept the day away on the sofa as usual, and apart from all the trays of seedlings which of course hadn't been moved this time looking pretty flattened or washed out, the garden appeared to have survived. Until I got up to the pond.
Expecting the water to be lapping at the edges I was horrified to find the level had dropped by about 20cm. This is not the first time the pond has emptied itself in times of flood, but we thought we knew why and had resolved it. The pond is built into the side of the slope and we'd previously thought that it was simply the force or quantity of water running down the slope that was forcing the liner away from the edge of the hole. It then appeared to be flopping over and allowing some of the pond water to run out behind it. We fixed this in May with a lovely big log. Pond Improvements Or so we thought.
But Monday morning, the scene was a whole lot worse.
It was quite clear that water had got right up and under the liner, forcing it up. The liner was clearly visible, a great black bulge right in the middle of the pond. Prod it, and you could feel the water ballooning underneath. A huge amount of water had clearly been pushed out during the night, no doubt carrying a lot of the juvenile wildlife from the gravelled nursery area (on the left in the photo above) with it. A disaster. I spent much of the day, which was fortunately cool and drizzley, using a watering can to put some water back into the pond and trying to recover any survivors in the rapidly drying gravel.
My wretched arthritic knees and shoulders limited me to eight cans of water on Monday, and another eight on Tuesday, but on Wednesday the full extent of the problem was revealed. It was way beyond a few watering cans!
The water beneath the liner had drained away, allowing the water in the pond to push the liner back into its original location. The shelf of plants on one side were all high and dry (top left); hopefully all the damsel and dragonfly larvae not to mention tadpoles had time to escape before it dried out.
The pond probably only had half of its water still inside, and needs far more than I can carry up the hill, two watering cans at a time. Plus we need to stop this happening - we need to put a drain in below the pond to stop water collecting in the hole which would mean beginning with a pit at least a metre deep, or but a big field drain on the hill slope above the pond to take runoff away from this area. Or just put up with it - not really an option as, if nothing else, the pond is now a wildlife trap, with steep sides that would prevent anything falling in from escaping, not to mention trapping the emerging palmate and marbled newts who should be leaving the pond at the end of the summer.
Sounds like I have a lot of digging to do this weekend, especially with more storms forecast on Saturday.
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