27 August 2018

Are a few days of rain sufficient to beat the drought?

Plantsoenendienst sproeit uitgedroogd grasveldje

The drought of recent months has had a visible effect on the Dutch landscape. The water level of the Rhine is historically low, green fields of grass are predominantly yellow and water reserves are depleting. All of the rain appears to have put an end to the worst of the arid conditions, but are a few days of rain sufficient to actually beat the drought?

‘Unfortunately not’, says drought expert Niko Wanders. ‘The groundwater in our soil plays a vital role in our water provision and drought control, but it is very slow to respond to rain. You see, roughly 65% of this rain will just evaporate again, which means there is not much left to help groundwater levels recover. The drought therefore does not simply just stop’.

Ground absorbs less

Wanders explains that a second consequence of drought is that, once it starts to rain, the soil absorbs less water. That is why the violent thunderstorms that we have so often seen this summer have little impact. They do lead to flooded cycle tunnels and basements, but do not contribute to the much needed repletion of groundwater stores. Even more rain is the only way of bringing an end to the drought, certainly in the east and south of the country.

Those violent thunderstorms have little impact. They do lead to flooded cycle tunnels and basements, but do not contribute to the much needed repletion of groundwater stores.
Niko Wanders

Too little water in the Rhine

Due to the drought, water levels in the Rhine are also historically low. Such levels at this time of the year were only previously recorded in 1949. This is a problem as all of the rainwater has to be used immediately to limit the effects of drought, as we are simply getting less water from the Rhine.

Groundwater levels need to recover

If groundwater levels do not recover this winter, it is highly likely that large parts of the Netherlands will face the same problems next year. We need the groundwater to ensure that we have sufficient buffers next summer.

Weeks of drizzle

So, is there a solution? ‘A week, or preferably weeks, of overcast weather with lots of drizzle’, says Wanders. ‘No-one likes it, but it would really help to get rid of this drought’.