Exploring the impact of drought on the drinking water provision

The year 2018 will enter the records as an extremely dry year and, perhaps, as far as the water utilities and water managers are concerned, ‘replace’ 1976 as the year of reference. The drought attracted lots of media attention and the drinking water provision was also frequently in the news. It seemed that the drinking water sector was able to manage the problems.

An extremely dry year is something that is part of the pattern of expectations, and water utilities and managers are thus in a sense already prepared for them. However, in the framework of the renewal of their provision plans, the water utilities are conducting an internal evaluation of the consequences of the drought for their operational management. Vewin, working with an external company, is evaluating the processes and communications within and outside the drinking water sector. And the Ministry of Infrastructure and Water Management is carrying out an evaluation through the ‘Droogte’ (Drought) policy table. Other entities, such as the Water Authorities and Rijkswaterstaat, are also undoubtedly doing evaluations of their own.

Test current knowledge and anticipate knowledge questions

Apart from evaluating the consequences of the drought in the summer of 2018, the experience also provides a unique stress-test to assess the current knowledge and to anticipate future knowledge questions. To this end, it is important to classify the 2018 heat and drought: How extreme was the situation? How applicable were the conditions as references for building new knowledge? This enables an assessment of how drought, and its associated aspects, are addressed by current research and the joint research programme with the water utilities, and where knowledge needs to be developed.

2018 as reference year

What new insights have the experiences of the summer of 2018 produced? What knowledge building is necessary to make use of the results of 2018 as a reference for research and policy? What aspects of climate change are relevant and already well covered in the current joint research programme, and what is still missing?

Objective

Within this exploratory research, we have analysed the extent to which 2018 can be seen as a reference year for studies into the effects of climate change on the drinking water provision, and for defining adaptive measures.

We have also studied the degree to which there is sufficient knowledge available about the consequences for the drinking water provision of extreme drought and heat, to allow us to decide on any adaptive measures needed. This has been done based on the following research questions:

How extreme was the heat and drought of 2018, and how extreme were the conditions in view of climate change in the future?
What were the consequences for the drinking water provision?
Did these consequences correspond to the expectations from earlier risk analyses into the effects of climate change?
What new insights arose and where are there still knowledge gaps?