Risk-based monitoring programmes for drinking water utilities

Since 2015, the EU Drinking Water Directive (DWD) offers water utilities in Europe a voluntary option to implement a risk-based approach to water treatment and delivery. With the recent revision of the EU DWD (2020-2184), implementing the risk-based approach has become mandatory. The main objective of this approach is to improve drinking water quality at the tap by focusing efforts more on the entire process of drinking water production and reducing risks to water quality well before reaching the consumer.

In the Netherlands, the provisions of the voluntary risk-based approach were implemented in the Dutch Drinking Water Regulation in 2017, and will be updated again shortly to comply with the revised Directive which came into force in December 2020.

A risk-based monitoring strategy offers the possibility to deviate from the prescribed parameters and sampling frequencies, provided that a thorough risk assessment is carried out. This allows for a clear focus on water quality parameters that are crucial to ensure drinking water safety, while at the same time reducing monitoring frequencies of parameters which are not relevant. This results in a cost-effective monitoring programme which provides exactly the information necessary to monitor and control drinking water quality from source to tap, and minimises the risk of quality issues that could affect public health.

In 2018, Benten Water Solutions helped Evides Water Utility in the Netherlands to establish a risk-based monitoring programme for its eleven drinking water production facilities, and prepared the risk assessment report for the Inspectorate as well as the overall monitoring plan from source to tap. The monitoring plan included eleven production facilities using either groundwater, surface water or a combination of both as a raw water source, and covered over 650 water quality parameters for each production facility at the source, at various locations in the treatment plant, in the distribution network and at the tap. The risk assessment and monitoring plan were approved by the Inspectorate and implemented by Evides Water Utility in 2019.