COLOGNE, Germany — For some, the first sign of the floods was the water at their door. Others said they had warnings, but no idea it would be so severe.

“Nothing,” said Amed Berg, a 29-year-old who lives in Sinzig, a town on the Ahr river where 14 people drowned last week in the floods that killed at least 165 people in Germany.

Firetrucks drove through the town and called on people to leave their homes over loudspeakers as floodwaters rose at about 10 p.m., but he said he didn’t hear them and didn’t have any warning beforehand. In other areas, evacuations began only when homes were already underwater. Even in places equipped with warning sirens, the systems did not sound in some cases.

As Germany picks up the pieces, questions are mounting as to whether more could have been done to warn people or evacuate them ahead of time to avoid such a high loss of life.

The tragedy has ramped up pressure on Chancellor Angela Merkel’s government just months ahead of September elections, with senior cabinet members conceding that the issue of whether enough precautions were taken needs to be investigated. There were mounting calls for her interior minister, Horst Seehofer, to resign.

“The timely warnings of the meteorologists have not been sufficiently communicated to the citizens by the authorities or by the public broadcaster,” Michael Theurer, a senior politician with Germany’s Free Democratic Party, told Germany’s DPA news agency. He spoke of a complete “system failure.”

Flooding had been expected. The European Flood Awareness System, designed to give early alerts, sent its first warnings to national authorities beginning July 10. More than 25 more warnings for specific regions of the Rhine and Meuse river basins were sent over the following four days, it said.

Franz-Josef Molé, head of the German Weather Service’s Forecast and Advisory Center, said that based on that information and other forecasts and satellite imagery, the service warned regional and federal authorities of “level three” extreme rainfall on the morning of July 12 for the region spanning from Dortmund in Germany’s west down to the Luxembourg border — two days before the area experienced the most serious flooding.

Level three means a dangerous weather event with a potential risk of serious damage, he added.

The following morning, the service issued a level four, its highest warning. Molé said that the weather service proceeded to inform federal, state and local authorities at a scale “never done before.”

“It was already clear how dangerous the situation was,” he said.

In Germany’s 16 states, decisions on disaster preparedness and response fall to local and state authorities. Molé said it’s officials such as local mayors who can best assess the needs of their communities and whether the situation warrants drastic measures such as evacuations.

But the level of flooding was just unprecedented, he said. “They had no clue how intense everything was going to become because we have never experienced something like this — it’s beyond comprehension.”

Some mayors also said that such decisions are not their responsibility. In the village of Altenahr, on a bend in the river Ahr, residents are used to flooding and many were alerted to the potential for high water levels through an app that tracks water levels and weather warnings from the German Weather Service. The initial warnings had been for flood levels of 11 feet, just below the level of 2016 floods that were the worst there in a century.

Hotels and guesthouses put up barriers and people moved their cars and garden furniture to elevations of at least 13 feet. By Wednesday afternoon, forecasts had risen to 18-foot waters, but there were still no orders for evacuation.

“There is no chance that I can evacuate people,” said the mayor, Cornelia Weigand, explaining that the responsibility for that order was at a higher political level.

Floodwaters eventually reached over 30 feet.

Hannah Cloke, an expert in flood forecasting at Britain’s University of Reading who developed the European Flood Awareness System, said even if the scale hadn’t been predicted, more precautions could have been taken.

“Even a flood of four meters [13 feet] is really quite big. People are very small and fragile, and they should not be in the path of floodwaters,” Cloke said. The major loss of life means that something went wrong with the warning systems, she said.

Cloke said that people need to have a longer memory of floods — and there have been much larger floods in the 1800s and 1900s.

“On top of that, you’ve also got a changing climate and a changing amount of rainfall,” she said. “I can believe that people were not expecting it to flood so much, but that also means there should be a better flood risk assessment before it floods.”

She said that local forecasters should have been looking at the impact on individual small rivers.

In Sinzig, Jetulla Muqa and his wife and three children had heard the firetrucks that were evacuating homes within 50 yards of the river Ahr, but he didn’t think the risk was real. It was only when he saw floodwaters streaming past that he scrambled out with his family. “We couldn’t believe it,” he said.

“It’s a small river; I can’t understand it,” said Andreas Geron, Sinzig’s mayor. “It was an experience no one can imagine.”

Elmar Mettke, a spokesman for the local fire department in Blessem, another village that suffered devastating flooding, said it wasn’t up to firefighters whether to sound the sirens and that decisions on whether to evacuate are fluid. Sirens are not “en vogue,” he said, with more announcements done through apps. But that involves people having them on their phones.

“It’s very difficult,” Mettke said. “If the water is at your door, you will leave your village, if the water is waist-level, you evacuate. We never in our lives expected a flood wave like that.”

Hiba Baroud, an assistant professor of civil and environmental engineering at Vanderbilt University, said that early-warning systems and evacuation plans are “crucial” to saving lives during extreme weather events, especially storms and floods, but they need to constantly evolve.

Warning systems in Germany need to get more in step with changing weather in the country, said Ralf Merz, head of the department of catchment hydrology at the Helmholtz Center for Environmental Research.

“These flash floods, which usually we can maybe observe in the Mediterranean and other warmer parts of the world, are now happening in Germany, and we need to adapt our warning system to that,” he said.

Flood defenses should be improved, and rivers given more space. “But finally, we have to think that maybe some of the houses, even if they have been there for the past 100 years, are in the wrong place,” he said.

Jennifer Hassan in London contributed to this report.