Lower fresh water usage, sewage treatment up to par

In 2021, 7.9 billion cubic metres (m³) of water was abstracted from the soil (groundwater) or from fresh surface water such as rivers and lakes. This is 4.3 percent less than in 2020. In addition, 6.6 billion m³ of seawater was used by the Dutch economy, 11.7 percent more than in 2020. The fact that less fresh water was used is mainly due a lower consumption level in agriculture and energy supply. Water companies processed 1,295 million m³ of water, equivalent to over half a million Olympic swimming pools.

The below flow chart displays water consumption in the Netherlands in 2021.

Lower agricultural water usage

In 2021, the agricultural sector used 124.4 million m³ of water, against 349.1 million m³ in the previous year, representing a drop of 64.4 percent. This means that water consumption in 2021 returned to the level of 2017 and earlier. The years 2018, 2019 and 2020 had relatively dry springs and summers. This led to larger amounts of groundwater and fresh surface water being abstracted for irrigating crops. Drinking water consumption remained virtually the same in the period 2003-2021. Drinking water is mainly used for livestock and cleaning stables.

Energy sector uses less fresh surface water

In 2021, power plants utilised 9.0 m³ of cooling water. As of 2012, the share of fresh water used for cooling purposes has become smaller and smaller. This is due to the policy of locating new power plants on the coast as much as possible in order to reduce dependence on fresh water. In 2012, cooling water consisted of 62 percent fresh water and 38 percent salt water. In 2021, this was 35 and 65 percent respectively.

Sewage treatment performance remains up to par

In 2021, sewage treatment plants treated 1.96 billion m³ of wastewater, 1.3 percent more than in 2020. The plants remove 98 percent of biodegradable pollutants from wastewater of households and businesses. In 2021, 85 percent of nitrogen compounds and 87 percent of phosphorus compounds were removed from wastewater, just as in 2020. As water treatment continues to improve, the residual discharge of nitrogen has decreased by 63 percent (from over 39 million kg to 14.4 million kg) since 1990. Residual discharges of phosphorus even dropped by 73 percent (from 6.2 million kg to 1.7 million kg). How well nitrogen and phosphorus fertilisers are removed is an important measure of the performance of sewage treatment plants.

More and more biogas converted into green gas

In 2021, sewage treatment plants produced more than 137 million m³ of biogas, over 15 percent of national biogas production. This was the highest output ever recorded and 6 percent up on the previous year. Over 60 percent of the biogas was used for electricity generation. Another 17 percent was converted into green gas, more than twice as much as in 2020. Green gas is often fed back into the natural gas grid for use by other parties.

More solar power used in water purification

8.5 percent of the electricity used for sewage treatment in 2021 (810 million kWh) came from own solar panels, a doubling compared to 2020. Own electricity production from biogas amounted to 175 million kWh, approximately the same as the annual consumption of 62 thousand households. The electricity still purchased in 2021 was almost exclusively green electricity.