Notices

Tilshead Borehole Levels: Sunday 31st March 2024

Happy Easter everyone! We’ve come to the end of the 2023-2024 flood reporting season and what a year it has been with 1.5 times the seasonal average rainfall in the Autumn and high levels throughout the season.  Whilst we’ve not seen the worst flooding there has been over the last decade, it has come a pretty close second.  We’ve had several cycles of rising then falling water levels and these have been replicated by the levels in the River Till.  At the start of last week, the water level was falling steadily, but then we had the mother of all storms on the afternoon of the 28th March!

If you were in the village, the deluge was spectacular to say the least.  Although there seemed to be a lot of water coming down, it was only 18mm – but most of it fell in a few minutes and not over the course of a day.  So we had a bit of lash flooding here in the village and also in the surrounding villages.   We don’t often reproduce raw Environment Agency data as it doesn’t provide enough information of the type needed to show historical changes, but this week was an exception.

Between 6:15 and 7:00pm in the evening, the water level shot up in the borehole by 270mm.  That is an unbelievable amount of water and it certainly isn’t a correct reading as it represents 15 times the amount of water that fell on the Plain during the same period of time  What had happened was that the ground surface near the head of the borehole had flooded and the water had poured into the borehole from above.  This was confirmed when it was announced the A360 had been closed at Tilshead due to flooding. The water level dropped very quickly, but has continued to rise back towards the top of the normal range over the last few days.  No other borehole in the vicinity showed the same spike, further confirming this was due to local flooding in Tilshead.

So how do water levels at the start of British Summertime in 2024 match those on 31st March in earlier years?

Well, it’s up in the top 20% of years, but not that spectacular in the greater scheme of things.

What is the weather going to bring over the next few weeks?  Well, you’ve got more rain coming later today which will last overnight and clear sometime tomorrow morning. So, this morning is the best time for an Easter Egg Hunt. The rest of Monday will be dry, and that will continue for most of Tuesday when the rain will return for a day or two.  This pattern of weather seems likely to repeat continuously until the middle of April.   The rest of the month could well be just the same, so possibly no respite from the wet conditions until May.

This is the last formal report for the 2023-2024 flood season. but we will keep an eye on things just in case the river levels start to rise again.  As we close, the Flood Alert for groundwater flooding on Salisbury Plain and for the River Wylye and its Tributaries remain in force and may well do for some time to come.  We hope to return in December 2024; in this guise or another.

Contains public sector information licensed under the Open Government Licence v3.0.

 

Winterbourne Stoke Parish Council