How full are our rivers and reservoirs?
After the announcement today that the final four water companies with hosepipe bans are lifting them with immediate effect, I thought I would take a look at the status of water resources across England and Wales – parts of the UK where drought has been an issue.
The weather has made a remarkable turnaround during spring and early summer. Just a few months ago there were serious concerns about our water resources following two consecutive dry winters – a time of year which is crucial for recharging them, especially groundwater.
Areas officially given drought status by the Environment Agency expanded with water companies across south eastern parts of England forced to put hosepipe bans in place. And then, as if by magic, the heavens opened and haven’t really closed since.
April was the wettest on record, with the first half of May cool and wet, only to be followed by the wettest June on record. If that wasn’t enough, the start of July has been a washout, with some places already having twice the average July rainfall in the first week of the month.
Despite the rain being much needed, I really do get a sense that most of us have had enough of the downpours and long for some summer sunshine.
So what is the status of our water resources? Well, the Environment Agency produce a weekly water situation report that keeps track of what’s going on.
Soil moisture deficits
Soil moisture deficits are a measure of how wet the soils below our feet are and give an indication of how much more water they can soak up.
At the moment, across most of England and Wales, the soils are close to or at full capacity. This has been a key factor in why flooding has occurred so often in recent weeks.
With the ground struggling to soak up any more rainfall, it flows over it, causing a combination of river and surface flooding.
River flows
This element of our water resources has seen a huge turnaround in the space of a few months. In early spring there were grave concerns at how little water was flowing through the river system and the impact this would have on wildlife.
Just three months later and rivers are full of water with flows at 80 per cent of sites now above normal or higher for this time of year.
This is another factor that enhances the risk of flooding. With rivers flows already above normal at many locations, heavy rainfall flowing into them can cause them to rise very quickly and potentially burst their banks
Groundwater levels
Remarkably, groundwater levels have increased during the past few months in quite a few places. This is unusual during the summer months as normally little water reaches deep down below the ground. It is often taken up by growing plants or evaporates because of sunshine and heat.
However, given the lack of these elements in the past few months, combined with the above average rainfall, the situation has got better, although groundwater remains below average across eastern England.
Reservoir levels
With the exception of four reservoirs, all are currently at average levels or above, with the majority of these at least 90 per cent full.
Looking ahead to the rest of July, there are no signs at the moment of any prolonged spells of warmth and sunshine. The weather is likely to stay unsettled with rain at times, interspersed with some sunshine.
Given that the ground is saturated, each time heavy downpours occur, there will no doubt be a risk that some places could see flooding problems – something that the Environment Agency will be keeping a close eye on.
On a lighter note, I made a time lapse video of the heavy showers that were over London yesterday. It condenses four and a half hours of video into just two minutes and shows just how quickly blue skies and become grey!