Big camphor tree base.

Due to the establishment of the buffer city, the low-lying area under the cliff in the eastern part of the inner city was used as a water storage reservoir.

Therefore, the underground drainage pipes in the inner and outer cities need to be adjusted from the drainage direction.

The original discharge to the lake on the cliff was adjusted to the discharge to the lower reaches of the river five kilometers away.

The area where the inner and outer city of Dazhangshu is built is originally on a higher ground, so the drainage pipes can be built along the lower areas.

The drainage system is quite complex,

At present, there are more factories in Da Zhangshu base, and a lot of industrial wastewater needs to be discharged. In addition, once there is a super heavy rain, if the drainage pipes are blocked by branches and other garbage, or the amount of water is too large, it will easily cause waterlogging disaster.

In order not to take up space on the ground, they adopted underground drainage.

Underground drainage pipes can be divided into two types: rainwater pipes and sewage pipes. Rainwater pipes are used to discharge rainwater, and sewage pipes are used to discharge sewage.

At this time, outside the buffer city, several pits of seven to eight meters and hundreds of meters long were dug on the ground. Cast-in-situ reinforced concrete was used underneath to construct a drainage channel more than two meters high.

.

Ding Jiu sat on the bed of a pickup truck and looked around at the construction site.

Looking at the design drawing in his hand, he was a little numb by the construction plan of the underground drainage system.

The horizontal and vertical marks on the drawings and the installation locations of the wires are all very detailed.

The drainage pipes run from the outer city to the buffer city and then outside. Cameras and two gates are installed at each drainage pipe gate.

The wires are connected to the waterproof electric door, and the door is intelligently controlled to open and close.

In addition to these drainage outlets, they also had to build preliminary flood discharge outlets, making the entire construction extremely complicated.

"Old Xu, what do you mean by the concave font design? Does it have any effect?" Ding Jiu looked at the drawing and thought for a while, then asked Xu Zhen who was standing aside.

Xu Zhen pointed to the line in front and said:

"Preventing backflow, and also better clearing the garbage in underground pipes."

Ding Jiu nodded and said: "Okay, the city lord has a hard standard, which is the safety of pipelines. Is your design feasible?"

Xu Zhen understood his worries and explained:

"certainly!"

"Not counting the blocking facilities in the buffer city, even after leaving the buffer city, there are five iron fence gates and electric gates. They are closed during dry seasons and can be opened during heavy rains."

"At that time, a sentry tower will be built at the drainage outlet, so there will be basically no problem."

With tens of thousands of acres of camphor tree base, it already looks like a small town.

It is unrealistic to rely solely on above-ground drainage and sewage discharge, and the construction of underground drainage channels is imperative.

However, when it comes to underground pipelines, safety issues are very important.

So Xu Zhen revised several versions before his design drawings were approved.

If an enemy wants to enter the buffer city through the underground passage, it is almost impossible.

Surveillance cameras, human detection devices, automatic switches at gates, etc. have effectively prevented this problem.

Ding Jiu put away the drawings, stood up and patted the roof of the car.

"Drive and go to the drainage outlet terminal to check the progress..."

"Okay, Mr. Ding, sit tight." The driver reminded and started the vehicle.

Then they came to a small river five kilometers away.

Because there had been no rain for several months, the amount of water in this small river was not large. Ding Jiu looked at the end of the drainage outlet built and asked Xu Zhen beside him:

"If a big flood breaks out, the drainage outlet here will be flooded, right?"

"Mr. Ding, don't we have a backup drainage pipe? Please bring out the drawing and I will show you..."

.......

.......

Mdu.

Since the outbreak of the apocalypse, parts of the coast have been flooded.

Even Chongdao Island has been submerged by sea water. With the strong sun in the past few months, the sea water has evaporated, exposing part of the soil that was previously submerged by sea water.

Tongshi.

Just north of M city.

Tongshi and Yancheng are mostly swollen coasts, with intertidal zones up to several kilometers wide. A large amount of garbage flows here with the tide and is scattered on the vast tidal flats.

Affected by the movement of ocean currents, a huge destroyer was pushed to the shore. As the tide receded, the huge destroyer ran aground.

There is a tidal flat below, and the entire hull of the ship does not touch the sea water.

"The tide is out, the tide is out, we can disembark, Smecta! Colonel!" a man from Bangzi Country shouted excitedly towards the cabin.

A white man with blond hair and blue eyes walked out of it. His eyes were red and filled with endless exhaustion.

The single-eyed man on the deck saw the white man coming out and shouted excitedly:

"Colonel, we can disembark now!"

Snap!

The colonel slapped the man in the face, his eyes showing excitement.

"FU*K, it's finally time to disembark. I don't want to be on the ship anymore! Notify everyone and get ready to disembark!"

Zhang Chengcan covered his face, feeling a little aggrieved.

No matter whether the colonel is happy or unhappy, he always slaps himself in the mouth and treats himself like a dog.

"Why don't you hurry up and inform everyone! FUC*K!" the colonel said angrily.

Zhang Chengcan left with his head lowered, his eyes full of resentment.

The colonel looked at the land not far away, with a flash of light in his eyes.

We can finally disembark!

Oh my God, only God knows what they have been through.

A few months ago, they came out of the port to search for food and fuel resources, but unfortunately they encountered a thunderstorm on the ocean.

The horrific natural disaster almost overturned their destroyer. Fortunately, they found a small island to avoid the wind and waves, and they escaped.

Later.

A terrible thing happened. After the thunderstorm and natural disaster, a mutant zombie appeared, a zombie that could climb onto the ship.

Originally, there were always some floating zombies in the ocean, but these zombies couldn't climb onto the boat, so they didn't pose much of a threat to them.

But!

The emergence of wall-climbing zombies makes the ship no longer safe.

Wall-climbing zombies climbed onto their ship at night, causing great damage to them. At the same time, half of the people on the already few people on the ship died.

The solar storm destroyed their ship's electronic equipment, leaving them with no GPS and the destroyer's missiles useless.

What's even more tragic is that while taking shelter from the wind and waves on a small island, the bottom of the boat was accidentally hit by a rock on the seabed, causing fuel leakage.

This isolated island is desolate and has very few natural resources.

Even if they wanted to get off the island, they didn't dare, for fear of the zombies in the ocean.

But....

Without fuel, the destroyers will have no power. They will be like rootless duckweeds in the sea. They can only drift everywhere, wherever the wind blows, they will go.

They squeezed out the last bit of fuel and drove the destroyer away from the island.

I followed the ocean currents on the sea and drifted with the wind and waves in heavy rains for more than five months.

The supplies were gradually depleted, and they even ate up the corpses of their own kind, fishing every day during the day.

Since fish are not mammals, they cannot be infected with zombie viruses.

It's just that these fish seem to be contaminated by nuclear wastewater, and they look a little strange.

But they are hungry and can't care so much. Eat!

They had no navigation, no power for the ship, no food, and no communication tools...

After that, I was in a daze, skinny as a stick, and my eyes were sunken.

Finally, driven by ocean currents, they were washed up on the shore and stranded after more than five months.

But they still dare not get off the boat because there are many zombies in the coastal waters.

Some are even floating on the sea, looking greedily at their bodies.

Although the hull of the ship ran aground, that was because the ship was too huge, with a draft of more than 5 meters. They had to soak in the water to get off the ship.

I would rather starve to death than be eaten apart by zombies.

But now, the tide has receded, and the entire ship is exposed on the beach.
To be continued...