Netherlands Closes All Rotterdam Locks in Historic Drought

The Netherlands has closed all locks in the Rotterdam-Den Haag region for the first time in history as severe drought threatens the country’s water defenses. The Hoogheemraadschap van Delfland (Delfland Water Authority) shut all four locks along the Nieuwe Maas river at midnight on August 5, 2026, and imposed a complete ban on extracting surface water across its entire management area, affecting approximately 1.5 million residents across 14 municipalities.

Unprecedented Measures

The unprecedented measures are designed to prevent salt water intrusion from the North Sea, protect peat dikes from drying out and collapsing, and preserve the region’s rapidly diminishing fresh water reserves. “We really have a gigantic precipitation deficit,” Nieske Dijkshoorn of the Delfland Water Authority told VRT NWS. “This is truly exceptional.”

The Parksluizen in Rotterdam are fully closed for both commercial and recreational navigation, while the Buitensluis in Schiedam, the Monstersche sluis in Maassluis, and the Vlaardinger Driesluizen in Vlaardingen are closed for recreational traffic. Closing the locks saves approximately 1 cubic meter of fresh water per second—about 86 million liters per day that would otherwise flow to sea, according to RTV Rijnmond.

The surface water extraction ban applies to the entire Delfland management area of roughly 400 square kilometers, affecting municipalities, businesses, greenhouse horticulture, agriculture, nature organizations, sports fields and clubs, golf courses, riding stables, and residents who use ditch water for gardens. “We are in an exceptional situation at this moment,” said Stijn van Boxmeer, a board member of Delfland, in the official announcement. “The fresh water supply in our area is decreasing rapidly, while we need that water urgently right now to prevent damage to our dikes, protect nature, and keep water quality as good as possible. We realize these measures have major consequences for residents and businesses, but intervention is now unavoidable.”

Historic Low Rhine Levels

The crisis stems from a historic drought that has pushed the Rhine—the region’s primary fresh water source—to record lows. Rhine discharge at Lobith, where the river enters the Netherlands, is around 650 cubic meters per second, compared to a normal summer flow of about 1,800 cubic meters per second. This is even lower than the minimum discharge during the infamous 1976 drought, which was approximately 780 cubic meters per second.

On July 30, the Rhine broke its 2022 record for the lowest level ever measured at Lobith, reaching 6.47 meters above NAP. The normal measurement station no longer functions due to the low water level, and a temporary measuring point has been installed. According to Rijkswaterstaat, 2026 ranks among the 5 percent driest years since 1906, as reported by Architectenweb.

July 2026 was exceptionally dry, with only 13 millimeters of precipitation nationally compared to a normal of 78 millimeters. The national precipitation deficit reached 248 millimeters by the end of July—twice the usual amount and only 20-30 millimeters below the record years of 1976 and 2018, according to the KNMI July 2026 climate report.

Salt Water Intrusion and Dike Safety

The low river discharge allows salt water from the North Sea to push further inland through the Nieuwe Waterweg and other waterways. The salt tongue currently reaches almost to Gouda. Delfland maintains a fresh water threshold of 350 milligrams of salt per liter; the Nieuwe Waterweg already measures 6,000 milligrams. If the Brielse Meer—a key fresh water reservoir—becomes salty, Delfland would lose two-thirds of its water supply.

“It is code black,” Van Boxmeer told NRC. “If the Brielse Meer becomes saltier, we lose two-thirds of all our water. Then we really have a problem.”

Dike safety is another critical concern. Many inland dikes in the Netherlands are made of peat, which must remain damp to maintain structural integrity. If peat dikes dry out, they become lighter and can collapse under water pressure. The 2003 Wilnis dike failure—when a peat dike collapsed due to drought, causing flooding—is cited as the worst-case scenario. “We need the fresh water to prevent our dikes from breaking,” Dijkshoorn said. “The last line of defense is that we let salt water into our system to keep the dikes safe,” Van Boxmeer added. “That has irreversible consequences for the ecosystem, but the safety of citizens comes first.”

Delfland has approximately seven days of fresh water reserves in storage, including the Wollebrand reservoir. Water levels in most polders have been raised to maximize retention. The Gemaal Winsemius pumping station moves 4,000 liters of fresh water per second from the Brielse Meer through a 4.2-kilometer pipeline to the Nieuw Oranjekanaal.

Impact on Agriculture and Communities

The measures have immediate consequences for growers and residents. Courgette grower Bert Doelman in the Westland greenhouse region told NOS that he has about ten days of water stored in silos. “My plants will be dead within a day if they don’t get water,” he said. “It is an extremely challenging year for growers,” John Kusters, chair of the Netherlands Fruit Growers’ Organization, said in a statement to AP News.

The drought is part of a broader European crisis affecting agriculture, river freight, and hydropower across the continent. The World Weather Attribution study, led by KNMI scientists, concluded that the drought is worsened by climate change. Soil moisture deficits in western Europe are approximately five times more likely due to 1.4 degrees Celsius of warming since the pre-industrial era, according to the KNMI attribution study.

What’s Next

The Netherlands escalated to drought level 2 (‘actual water shortage’) on July 16, and further measures may follow if conditions do not improve. Delfland officials say the locks will remain closed and the extraction ban in effect as long as necessary. “Previously it was a theoretical model,” Van Boxmeer said. “This is the here and now.”

A single heavy rainstorm will not be sufficient to restore water levels. “It needs a long period of rain,” Dijkshoorn concluded. Until then, the Netherlands—a country that has spent centuries fighting water—finds itself in the unprecedented position of closing its locks to hold onto every precious drop.

As climate change makes such extreme droughts more likely, Dutch water authorities are confronting a new reality: the nation’s legendary water management system must now be designed not just to keep water out, but to keep water in.