This category contains flood alert information, in particular the water levels in the Tilshead Borehole. Graphs will be published weekly from 1st December through until the end of March.

Tilshead Borehole Levels: 22nd February 2019

An interesting week, with very little rain (4.3 mm).  However, rain from the previous two weeks has clearly continued to feed into the aquifer, so the water level has continued to rise, albeit at a declining rate.

We are still 5-metres below the six-year average, but plenty of time before the end of March to see a huge difference.

We are not expecting much in the way of rain until the end of the month, but the signs are building for a series of rain-bearing Atlantic fronts to work their way over us in early March.

Tilshead Borehole Levels: 15th Febuary 2019

A very interesting week as far as the borehole levels go.  As we’ve said on a number of occasions over the years, once the water level in the aquifer exceeds the 85 metre mark, the whole system becomes very sensitive to even the slightest amount of rain.  so it has proved once again.

With just a little bit of rain, the aquifer level has increased over 2 metres in a week.  The last 2 metre rise took over a month.  Of course, we’ve now had a further 3 days without rain and the temperature has started to increase; but I suspect we are not through with winter just yet and we may have another cold spell or two before spring really gets into gear and trees start to come into leaf, slowing the rate of increase in the aquifer, even if we get a lot of rain.

The forecast is for a largely fine weekend, although we may get a spot of rain overnight tonight.  Early next week we may see a little more rain by Tuesday and Wednesday.  There seems less and less likelyhood of snow in early March and the weather here in Wiltshire is going to be coming off the Atlantic than from Continental Europe.

Tilshead Borehole Levels: 8th February 2019

Apologies for being a day late – the delay was down to heavy rain, traffic on the A303 and the gas leak on the Packway.

Well, its been a very interesting week as far as the waterlevel goes. Despite the heavy rain we’ve had, the water level dropped, then held steady for most of the week, only beginning to rise again in the last couple of days.

As you can see, the water level in the aquifer remains very low and it’s going to take an awful lot of rain between now and Easter to make up for the 17 metre shortfall in the aquifer level from the average at this point in February.  That said, there is an awful lot of variability in the data and as a consequence, this year’s rainfall is only pulling down the 6-year average by 1.5 metres.

The weather is going to be the decisive factor, as always.  We should expect quite a bit of rain today and tomorrow, clearing on Monday and Tuesday, with a spot more rain towards the middle and end of the week; but no deluges of biblical proportions.

There seems to be little confidence in how things will unfold towards the end of the month and into March, but there could be a lot more snow to come.   Don’t put your sledges away just yet!

Tilshead Borehole Levels: 1st Feb 2019

We began the week with a little light rain and ended the week and January with a moderate snowfall.  None of this has had any noticeable impact at all on the rate of increase of the water level in the Tilshead borehole.  In fact, the level fell on one day of the week and has barely stayed level.  If we don’t get a lot more rain in February and March, we could be in for a very arid summer.

After the wettest December in 6 years, we’ve then had the dryest January in six years, with less than half the amount of rain (26mm) seen in the second dryest January – that of 2016-2017 (60mm).  It is still snowing lightly as I write, but this is due to stop in the next couple of hours; in any event, it’s not going to have a significant impact on the water table.   The forecast for the next few days is for a few showers, clearing to the east by Tuesday.  In the longer term, there is still uncertainty as to whether the weather will be dominated by warmer and wetter winds coming off the Atlantic, or further cold weather coming in from Siberia.

Tilshead Borehole Levels: 25th January 2019

As predicted, we had a little rain over the last week; around 15 mm.  However, that appears to have had little if any effect on water levels in the Tilshead borehole.  The rate of increase has dropped steadily during the week, so it seems the rain that fell is simply refilling a dry part of the aquifer rather than increasing the the depth of the water table.  It’s a bit like taking a wet sponge (December) with water pouring from it.  Leave the sponge to run, then drip for long enough then the flow of water all but stops.  Start adding water to the top of the sponge and fist of all it gets sucked into the top of the sponge and little goes all the way through.  If you add too little water, then it’s entirely possible it has no meadurable effect on the overall rate of flow.

This years rainfall has dragged the average borehole level for today down by about 1.3 metres on last years 5-year average measure.  That’s quite a lot.  We have a little rain forecast for the weekend and into the early part of next week, before the weather gets colder again.  Snow is still on the cards for Tuesday.  After that, the weather is looking increasingly complex with cold snaps being replaced by warmer weather, increasing the risk of some disruptive snow.   I’ll believe it when I see it.