Chapter 11 — The Thirteenth Landmark

Cycle 13 does not open a single valve. It activates the pumps simultaneously in programmed order, pushing water from the Can lagoon in three directions. In the compartment, the control panel shows red arrows woven like blood vessels.

“If the controller is not stopped, the auxiliary valve will open automatically after nine minutes,” Nam said.

“Where to turn it off?”

“Central server.”

“You just lost your rights.”

“There is a manual access line.”

Khoi supported his shoulder, still trying to keep his voice calm. “Which way?”

Nam pointed up a steel ladder leading to the technical floor. “The transmitter is on the pressure tower.”

An didn't want to ask how much gas was in there. Khoi's meter was flashing yellow. They only have a few minutes left.

Nam opened the old control box and took out a wire with a magnetic head. “Your father used this to bypass the automated system.”

“How many things did he leave behind that we don't know about?”

“Enough for others to continue living.”

Khoi climbed first. Each step vibrated under his weight. An followed, holding the lifeline. Male is at the end, carrying the controller.

The technical floor is only as wide as the hallway, with pipes running on both sides. An old pressure recorder placed in a glass box, the dial stopped at 3.17 meters. On the lid there is an engraved line: "Do not average while the water is accumulating".

An took a quick photo, then looked for the transmitter. It is located behind a steel plate, connected to the antenna line facing the center. Male attached the magnetic wire, but the indicator light is still red.

“Need the confirmation code of the person in charge first,” he said.

"Who?"

“Your father.”

“He's dead.”

Nam looked at the key in her hand. “Mile 13 holds the mechanical code.”

An took the piece of label B-13 and turned it over. Under the glue was the number 319742. She entered it on the keyboard. The red light turns yellow, then green.

Manual signal is activated.

"Hour?" An asked.

“A command to stop pumping can be sent.”

Nam typed quickly. The screen shows an error: “Insufficient permissions.”

Khoi looked at him. “You said there is a manual way.”

“I'm halfway through.”

An took the B-13 voice recorder and played the file in her father's voice: "Can't open any more. Waiting for hospital confirmation." The sound recognition transmitter displays a box requesting biometric confirmation.

“Mr. Vu uses voice as a key?”

“He was afraid the code would be taken.”

“Now we have to imitate the voices of the dead?”

Nam looked at the speaker box. "Not an imitation. Use the full thirteen-second recording."

An cuts the file according to the instructions. The machine receives the signal, but requires another confirmation. She searched through the audio files. File number nine has the father's voice reading: "The hospital still has the transmitter."

Men combine two segments. Green transfer system.

“The stop order has been sent,” he said.

Three pumps stopped. But the auxiliary valve still opens by inertia. Water continues to overflow into the western regulating lake.

“We have to go up to the dam,” Khoi said.

They turned down. When leaving the compartment, the water had risen to the level of the stairs. Khoi gritted his teeth because of his injury, but still went ahead. A cracked pipe sprayed chemical vapor, making An dizzy.

Nam pulled her through the door. Going outside, they found the North Bank submerged in water up to the wheels. Red warning lights cover the whole city.

Bich stood on the roof of the rescue vehicle, broadcasting live. She gave An a spare phone.

“The signal just went off for ten seconds, but viewers can still hear the sound.”

“What did you give out?”

“Milestone 13.”

On the screen, tens of thousands of comments ran quickly. Some people sent videos of door number three opening. Another person sent a photo of the land price map. Bich read each piece of evidence without adding comments.

“I need you to speak on the phone,” she said speak.

“I'm not a spokesperson.”

“You're the only one who can explain the error.”

An looked at the water flowing across the square. She held the phone.

"The mechanical meter and the electronic system are giving two different numbers. We have taken water samples at the outlet and are sending them for independent testing. People do not need to move from the high areas yet, but do not go onto the southern routes."

A man's voice rang out behind him: "You have no right to say that."

Dang Quoc Duy stood on the technical bridge, his shirt still unusually dry. The person wearing the silver ring is holding a walkie-talkie. Two security guards accompanied.

Khoi stepped forward. “This road is no longer part of your construction site.”

“This is city infrastructure.”

“So why are you standing next to the control panel?”

Duy looked at An. "You turned off the automatic system. If the western area floods, you will be responsible."

“I turned off the chemical pump.”

“You don't know what that is.”

“The independent laboratory knows.”

“A sample not sealed by the regulatory agency.”

An raised the camera. “The handover sequence is being recorded.”

Duy looked at Bich. “Miss journalist, do you want to be a hero based on other people's fears?”

“I want you to make the log public,” Bich said.

“I have no obligation to respond to a livestream.”

“He has an obligation to respond to the residents standing in the water.”

Duy walked down the bridge. A guard reached out towards An's device. Khoi stopped it.

“Touching the machine is an act of hindering rescue,” he said.

Duy looked at the blood on Khoi's shoulder. "You're already injured. Don't make it worse."

“It's been bad since I opened the valve.”

Duy signaled withdrawal. Before leaving, he told An:

"You want to know who the last signer is, right? Hoang Nam is not that person."

“You know?”

“I know that person is standing next to you.”

Duy pointed to the South and left.

Nam turned pale. “He lied.”

“Or are you lying?” Khoi asked.

Nam did not respond. He looked at the screen at Milestone 13. The water needle stood at 3.17, then moved one more line.

Bich gave An a text message he had just received: The anonymous source wants to meet in the old station. Sender's name: N.

An looked at Nam. “Are you N?”

"Are not."

“So who?”

Nam turned toward the city, where water was pouring over the old railroad tracks. “That person will tell you why your father accepted the money.”

“You know?”

“I know he accepted it to buy one night.”

“Buy it for whom?”

Nam looked at An, his voice almost whispering:

“For you.”

A rescue siren sounded for a long time. The water in the western regulating lake exceeds the edge. On the RiverEye screen, the official system still shows safe water levels.

Milestone 13 is the only device that says the city is flooding.

An asked Phuc to open the resident's manual record on the school screen. The numbers are not as pretty as the RiverEye chart: people used a wooden ruler, some people recorded the wrong time, and some places had a power outage so they could only measure twice. But when you overlap the points, the trend becomes clear. Real water rises along the south bank, while the electronic system lowers the numbers at stations near the project.

“This is statistical evidence,” Bich said. “Not a single landmark.”

Nam looked at the chart. “If we bring it up, they will say people don't have the expertise.”

“And I have expertise,” An replied. “Tell me what you see.”

Nam stood in front of the camera, explaining how optical sensors are affected by turbidity, how the averaging filter erases pressure peaks, and why a forty-centimeter difference cannot be called network latency. His voice trembled in the first sentence, but came The last sentence has become certain.

The video is played back many times. A group of engineering students submitted an independent analysis, validating the model. People began to name measuring points after their streets. Marker 13 is no longer a secret object; it became the common symbol for inspection.

Meanwhile, Khoi brought rescue teams to low areas. He no longer uses the center's orders, relying only on the population meter and the sound of pumps. Some people didn't believe it at first, but when they saw the water receding in the street with the old valve, they started calling him "water level Mr. Khoi".

Hearing that, An laughed for the first time in many days.

“Can you smile?” Bich asked.

“I'm calculating the wrong number.”

“Which number is wrong?”

“The difference between a rescuer and a hero.”

Bich shook her head, but the camera was still recording.

That evening, Hoang Nam received a call from an unknown number. The person calling is his mother, in the northern area. She said someone came to ask about old drawings in the house.

“Mom, don't open the door,” Nam said.

“They said I quit my job.”

“Mom kept saying I was on a business trip.”

“Are you really on Ms. An's side?”

Nam looked through the window and saw An examining the water sample under the light. “I'm on the side of the living.”

After the call, he gave An a small key.

“The door to the center's records room,” he said. "I can't open it remotely. You need to see the original commands."

“You're not coming along?”

“I will create a distraction.”

“You've created enough of a distraction.”

Nam smiled sadly. “Then let me do it right this time.”

An and Bich arrived at the center when the water had just flooded the lobby. The file room door was guarded by security, but a side door remained open. An used the key to get inside. Rows of cabinets contain sewer logs, maps and recovery records.

They found a box labeled “12.09 — unused copy.” Inside is an order to open the sewer signed by Trang, Duy and a person named Vinh. Her father's signature is missing.

An took a picture, but before leaving, the room light turned red. A voice from the internal speaker rang out:

“Miss Lam, please put down the documents.”

That's Nguyen Dieu Trang's voice.

An looked at the camera on the ceiling. “She's watching us.”

“I'm protecting the records.”

“Records don't need protection if they're clean.”

“You don't know who you're touching.”

"I know. I just don't know which side you'll be on when the water recedes."

An left the room with Bich. Behind the back, the system locks the entire cabinet. But copies were in four phones.

Outside the center, Nam was stopped by two security guards. He did not resist, just told An:

“Don't let them make me the reason you stop.”

An watched him being taken away. She knew from now on, there would be no one inside to help them open the door.