Chu Ze had already prepared, and immediately said: "Your Majesty, my lords, the sediment in the Wei River is all from the upstream. Before Jingshan, the Wei River was turbulent, and the sediment flowed with the water, but after leaving Jingshan, the river water slowed down, especially when it flowed to the Guanzhong Plain, the water flow was gentle, and the sand in the water naturally precipitated. ”

Chu Ze paused, glanced at the water on the table, really wanted to drink, and after saying so many words, he was very thirsty. His Majesty Li Er said with a smile: "Show Chu Aiqing tea." ”

"Thank you, Your Majesty!" After taking a sip of water, Chu Ze continued, "Therefore, if you want to treat the water of the Wei River, you must first treat the sand of the Wei River." Otherwise, piling up the embankment and digging the deep riverbed is only an emergency measure to treat the symptoms but not the root cause, and it is inevitable that the Wei River will often burst the embankment. ”

"Of course, as I just said, it will take a hundred years to solve the root cause, and we have no way to stop the sediment from being deposited in the middle and lower reaches until the root cause is completed. Therefore, it is necessary to find a way to make this sediment not deposited in the middle and lower reaches, but washed into the sea by the water of the Wei River. ”

"The governance of the Wei River should be done by taking advantage of the trend. Since the water of the Wei River can bring sediment, it can also carry away sediment. ”

"How do you take the sediment away?" Cen Wenwen is a reasonable person, after listening to Chu Ze's analysis of the Wei River flood just now, his perception of Chu Ze has changed greatly, and he will ask half for advice and half with emotion.

Chu Ze Chongcen Wenwen smiled slightly, and said to His Majesty Li Er: "Naturally, we are trying to find a way to increase the flow speed and momentum of the Wei River. To put it simply, it is to make the Wei River flow as it was before Jingshan, so that the Wei River flows rapidly. ”

Chu Ze said: "Of course, if you want to completely change the topography of the Weihe River, that is not something that mortals can do. But we can make the Wei River flow turbulent for a short time, or every now and then, to wash away the sediment. When the sediment settles again and is about to cause flooding in the Wei River, the water flow of the Wei River becomes turbulent and washes away the sediment. ”

"Yangquan County! We all know this truth, but the question is how to make the Wei River flow turbulent from time to time or in a short period of time, as you said? Fang Xuanling asked.

Chu Ze smiled slightly, and said the final method: "Build a reservoir." ”

"Build a reservoir?" Everyone didn't know what to do, and their faces were full of questions. On the contrary, after Cen Wenwen's body was shocked, he was thoughtful.

Chu Ze smiled slightly and said, "The so-called reservoir, as the name suggests, is naturally to store water, and to put it bluntly, it is a man-made lake. ”

"The method I am talking about is that a part of the Wei River water is impounded, and then suddenly put this water into the Wei River, which will inevitably make the Wei River flow turbulent, so as to wash away part of the sediment in the middle and lower reaches of the Wei River, so that the river channel will be deepened, the sediment accumulation in the middle and lower reaches will be improved, and the flow capacity of the river will be improved, which will naturally reduce the flood problem of the Wei River."

Chu Ze said the common methods used in later generations to control floods and clean up the silt in the river. As for the effect of this method, it has been repeatedly verified and proven by later generations, but he does not have to worry about it at all. What worries him is that the construction of the reservoir is not the work of months, but the work of years. Of course, it is much easier than planting trees and grass on the Loess Plateau and the barren mountains of Longxi, Guanxi and Hexi.

The truth of the reservoir method mentioned by Chu Ze is actually very simple, and it is easier for people to understand than the previous explanation of soil erosion, planting trees and grass. Even when they were young, they played the game of blocking the water in the creek and then suddenly letting go and watching the water rush by.

Everyone figured out the truth of this, and all of them looked uplifted, and Cen Wenwen sighed even more, saying: "I'm really old and confused, after so many years of studying the way to control the flood of the Wei River, I only thought of a stupid way to make people dig sand." Why didn't you think of this method? I was so stupid. ”

The eldest grandson Wuji thought of more, thought about it for a while, and said to His Majesty Li Er: "The law of the reservoir mentioned by Yangquan County is simple and should be feasible. And the minister just made a simple calculation, the method mentioned by Yangquan County will not use too much labor, and my Datang can still bear it, and it will not affect the normal life of the people. It's just that the time it takes to do this method is not a year's work, and I'm afraid it will take three or five years! ”

His Majesty Li Er frowned slightly, but then smiled, he was too greedy, he was able to solve the problem of flooding in three or five years, which had not been solved for a long time, and he was already fortunate to be able to do so, if Chu Ze had not proposed this method, I don't know when people would have thought of this method.

Alas! It's also strange to say, some methods of things in the world, after thinking of it, and after putting it forward, I feel that the truth is indeed very simple, but no one can think of it for many years.

Chu Ze had the same emotion as His Majesty Li Er at this time, thought for a while and then said: "In fact, in addition to adjusting the speed and impulse of the flowing water, so as to wash away the silt, there are at least three benefits of building a reservoir. ”

Without waiting for everyone to ask, Chu Ze immediately said: "It rains in the sky, and the rain is more and sometimes less, and there are floods, flooding villages, towns, and fertile fields. There are also times when there is drought and little rain, and the people's fields are not harvested. After the construction of the reservoir, when the rainy season is too much rain and the flood is raging, the flood can be discharged into the reservoir to a certain extent, which can reduce the water surface, reduce the pressure of the downstream waters, and weaken the flood situation. When there is a drought and lack of rain, the water in the reservoir can be used for drinking and watering the fields. ”

Everyone was overjoyed when they heard it, judging from the reactions of several important ministers at this time, regardless of whether they were greedy or not, whether they were corrupt officials or mediocre officials. But they are all dedicated to the country and want to make the country better. Not to mention His Majesty Li Er, he wanted to be the Emperor of the Ages, the Emperor of the Ages, and the construction of the reservoir had such benefits, and Chu Ze did give him too many surprises today.

Cheng Da Demon King was also very emotional in his heart at this time, ": This cheap nephew of himself really gives himself a long face, it seems that he can't write a twist and turn and don't have to be afraid, who dares to laugh at me Lao Cheng at that time, I Lao Cheng asked him, is there a nephew who can manage the flood, haha, very beautiful." ”

His Majesty Li Er was the first to come back to his senses from the surprise and said to Chu Ze: "Chu Qing! You just said that there are at least three benefits to the construction of the reservoir, but what are the other two benefits in addition to what you just said? ”

Under the attention and speculation of everyone, Chu Ze said again: "Return to Your Majesty! In addition to the benefits of washing away silt, flood discharge, drought prevention irrigation, and drinking water for people and animals, reservoirs also have many benefits.

For example, the water quality of the Wei River has always been very poor, but when it is placed in the reservoir, it will gradually become clear after a long time, which is more convenient and healthy than the people drinking the water of the Wei River directly.

In addition, when there is an urgent need for the Wei River waterway to transport grain, grass, and troops, but in the dry season, the water of the Wei River is too shallow, and it is difficult for large ships to get into the water, the reservoir can also be opened to solve the temporary needs. Well......... That's all I can think of at once, and maybe there will be other benefits when the reservoir is built. ”