Although it seems to rain a lot in the UK, this year we’ve had one of the hottest summers on record and rainfall levels are lower than normal. This has led to a hosepipe ban in most areas of the UK to save water wastage and to prevent water levels dropping any further.
Is the UK still in drought?
Yes, as of early December 2022. It will take some constant good and steady rainfall to replenish the UK’s reservoirs. Rainfall levels are not expected to be high enough to bring reservoirs back to normal levels until after the winter.
What is a drought?
A drought occurs when less than 0.2mm of rain falls over a period of 15 consecutive days. Up until August the only month to have above average rainfall was February. July was the driest month since 1935. This led to many regions in the UK declaring drought conditions.
Hot, dry weather can lead to one or more of the common types of drought which are:
- Hydrological drought – Rivers and reservoirs having low levels of water
- Agricultural drought – Farming and crops are effected by lack of rainwater
- Meteorological drought – Caused by below average rainfall
- Ecological drought – Lack of water effecting the local environment
Why is this happening?
The long hot summer and the lack of rainwater has caused the drought conditions.
When it rains the water soaks into the ground where it is stored as groundwater. If the weather is particularly dry groundwater levels decrease. Groundwater is better known as the water table.
The water table levels are dictated by aquifers. Aquifers are layers of rocks in the soil which store water and pass water into our rivers. The water we use is taken from the water table using boreholes which can represent around 30% of the water we use. The rest is taken from rivers and stored in reservoirs.
Some rivers in the UK are said to be exceptionally low because water levels have fallen below 50% and this is why we are still in drought.
What do water companies do when a drought is declared?
Normally the water companies begin by implementing a hosepipe ban which saves water from non-essential use. They can also reduce water pressure from the mains and look for and fix water leaks.
What is the current situation?
The Environment Agency published a summary of the water situation in October 2022 which was updated in the middle of November.
In the summary it confirmed that rainfall was above average in most areas. This meant that the soil moisture was improving but was still not back to pre-drought levels.
Rivers in most places are flowing with normal water levels, although there are still some places with below average or low levels.
Groundwater and reservoir levels are still below average.
What needs to happen for the UK to be out of a drought?
Basically, it needs to rain with above average levels of rainfall. Average rainfall in the UK is 800mm to 1,400mm each year. Rainfall is normally measured as:
- Light rain – 0.5mm hourly
- Moderate rain – more than 0.5mm but less than 4.0mm per hour
- Heavy rain – More than 8mm per hour
Up to July in the UK we only had 15.3mm of rain when the usual amount should be around 65mm. So, as you can see from these figures, we need the rest of the year to give us above average rainfall to end the drought by the end of the year.
Unfortunately, this doesn’t appear to be the case because the official line is that we will still be in drought beyond the spring of 2023.