In the autumn and September of the tenth year of the Han Dynasty, Xinwei (the eighth day of the first month).

On the third day after arriving at the lower reaches of Zhengguoqu County, Liu Ying finally waited for the belated Shaofu Yangchengyan in the Lianshao County Ya at the foot of the temporary pillar.

In fact, Yangchengyan set off from Chang'an, several days earlier than Liu Ying, and it stands to reason that when Liu Ying arrived at the lotus spoon, Yangchengyan should have waited here early.

But in fact, the first stop after Yangcheng Yan departed from Chang'an was not the lotus spoon located on the south bank of the lower reaches of the Zhengguo Canal, but the three plains located in the middle and upper reaches of the Zhengguo Canal.

As for the reason······

"How is the Shaofu doing with the survey of the canal?"

After a brief greeting, Liu Ying didn't detour much and went straight to the point.

Hearing Liu Ying's question, Yang Chengyan couldn't help but look a little pale.

"It's all over the house."

"Four days ago, the minister had sent Shaofu water workers to it to cut off Zheng Guoqu in Jingkou."

"The post-ministers went to see it in person, and carefully probed with the craftsmen of the Shaofu Hydraulic Engineers, and finally got this time, the detailed case of the renovation of Zheng Guoqu."

As he spoke, Yang Chengyan did not forget to take out a roll of bamboo slips stained with a little dry mud from his arms and handed it over to Liu Yingshui.

Taking advantage of Liu Ying's reading, Yang Chengyan also narrated on the side: "The minister has calculated that the construction of the Zhengguo Canal, all the canal sections west of the three plains, all more than 60 miles, should be filled in the bottom of the canal to increase its topography. ”

"There is no urgency in this matter; When the winter solstice is frozen, the downstream plug is dredged, and then it is not too late to fill the soil. ”

"And the one hundred and seventy miles east of the three plains and west of the lotus spoon, there are nearly one hundred and fifty miles, and there is no need to fill in the soil and dig the mud."

"If you have time, you can dig a little mud in the ditch and replace it with soil; If you don't have any leisure, you can don't. ”

Listening to Yang Chengyan's narration, Liu Ying also nodded slightly.

That's right.

After setting off from Chang'an, Yangchengyan rushed to the head of the canal where Jingshui flowed into Zhengguo Canal as soon as possible.

In the next few days, the only work of Yangchengyan was to check and calculate how each section of Zhengguo Canal needed to be renovated from west to east, that is, from upstream to downstream.

The entire Zhengguo Canal, especially the middle and lower reaches of the canal, has been widened, which is needless to say.

The most important thing is to calculate the renovation plan of each section of the Zhengguo Canal.

That is: how much soil needs to be filled in the upstream parts?

Which parts of the midstream can be left alone, and which parts need to be maintained and repaired?

Of course, the most important, and the most urgent at the moment, is to be blocked by sediment, causing the water to slow down or even close to the bottom of the stream, how deep do you need to dig?

Yang Chengyan quickly gave an answer to this question.

"The first thing to do in this repair of the Zhengguo Canal should be to dig and dredge under the downstream blocked canal section; The specific section of the river starts from 20 miles west of the lotus spoon and ends at the end of the Zhengguo Canal into Luoshui, a total of 110 miles. ”

"And the depth of the digging sediment, the minister intends to calculate: this one hundred and ten miles, the first ten miles should be dug more than two feet, and then every ten miles added, the bento should be dug one foot more."

"At the end of the Zhengguo canal, dig a foot three feet deep······"

Listening to the specific data given by Yang Chengyan, Liu Ying couldn't help but be a little surprised.

- Three feet long, but nearly three meters!

In other words, in just 13 years since the second Qin Dynasty, the Zhengguo Canal, which has not been systematically maintained, has deposited at least three meters of sediment downstream!

You must know that back then, when Qin Xiang Lu Buwei repaired Zheng Guoqu, the depth of Zheng Guoqu was only three zhang!

That is to say, the original Zheng Guoqu, which was nine zhang wide at the bottom, fifteen zhang wide at the top, and three zhang deep, has become now that the bottom is 15 or 6 zhang wide, the top is more than 20 zhang wide, and the depth is less than 2 zhang.

The canal is heightened by the accumulation of sediment, and the width of the canal is increased by the widening of the people and places······

It can only be said that Zheng Guoqu can still flow so far, and it can barely be used to divert water to irrigate the fields, which is already a big miracle!

This time, Liu Ying was ordered by Liu Bang, the son of heaven, to renovate the Zhengguo Canal, and the reinforcement of the upstream water and soil and the widening of the entire canal were still secondary.

The most important, and the most urgent, is directly related to the flow of water in Zhengguo Canal next year, and the agricultural water used by the people of Weibei, or the downstream, that is, the section of 110 miles that Yangcheng Yanfang just said, that is, the dredging of the blocked river section with a length of about 45 kilometers.

It is only necessary to dig the bottom of the 110-mile blocked section of the canal from the current depth of 7 or 8 feet to the original depth of about 3 zhang, and the condition of the Zhengguo Canal will be greatly improved.

As for laying the upstream with stone bricks and silicon, fixing the civil engineering, filling the soil to reduce the width of the Zhengguo Canal, and even washing the sand in the middle and lower reaches, there is no need to be too anxious.

From the 8th of September in autumn, to mid-to-late October, when the temperature in Guanzhong cools down, the river is frozen, and the sediment at the bottom of the canal is frozen soil, there is only more than a month left.

In other words, Liu Ying is left with only about 40 days left to dredge the blockage of the downstream section of the river and complete the most important part of the renovation work of the Zhengguo Canal.

Thinking of this, Liu Ying's face also had a little urgency.

"When can the dredging of the canal be started?"

"Also, in recent days, those who have come from Weibei to serve as the force of canal renovation have won a few people?"

seemed to feel the urgency in Liu Ying's heart, and Yang Chengyan's expression couldn't help but feel a little serious.

"Zhengguo Canal, since the head of the canal has been cut off from water for four days, two days after tomorrow, the mud at the bottom of the canal is slightly dry, and the construction can be started to dig the downstream mud!"

"and ······ of forced labor"

Speaking of this, Yang Chengyan paused, and when he looked at Liu Ying, a touch of sincere admiration gradually surged up.

"By the end of the day, there have been more than 14,000 people from Weibei!"

"If you don't count a few days, I'm afraid it's twenty-five thousand; When the work is a little time, it may be possible to complete the renovation work downstream before the winter solstice! ”

From Yangchengyan's mouth, he learned that the problem of forced labor had been roughly solved, and the sense of urgency in Liu Ying's heart eased a little.

"In this way, the lack of forced labor should be safe."

——In a few days, the officers and soldiers of the Northern Army and the Zhonglang General will go to the straight roads in various parts of Weibei to repair the straight roads that are crushed by stone bricks!

At that time, let alone twenty or thirty thousand, even if forty or fifty thousand strong laborers came spontaneously, Liu Ying would not feel strange at all.

The problem of forced labor is solved, and the last thing that remains is the specific construction plan.

Thinking of this, Liu Ying got up from the seat at the top, picked up a brand-new parchment scroll from the desk in front of him, and handed it to Yang Chengyan.

"This repair of Zheng Guoqu should be based on the meaning of Shaofu, and Lone should not interfere."

"However, this is a lonely strategy, so I dedicated it to Shaofu in front of me to ask if it is feasible?"

Liu Ying spoke hard, and the brand-new parchment scroll had also been spread out by Yang Chengyan and placed on the wooden case in front of him.

Then, Yang Chengyan saw the parchment scroll on it······

Only six lines?

To be exact, it is six lines of varying thicknesses that are parallel to each other.

Looking at the 'construction drawing' that looked like a runway she had drawn, Liu Ying couldn't help but blush a little, stepped forward, and pointed her finger at the middle of the parchment roll.

Leaning forward with Liu Ying's fingers, and looking closely, Yang Chengyan found that in the center of the six parallel lines, there were several fingernail size fonts, which seemed to be used as marks.

"Bottom of the ditch······ ······ at the top of the canal"

muttering to himself, Yang Chengyan's face quietly swelled up.

I saw Yang Chengyan raise his head slightly, looked at Liu Ying with an uncertain face, and pointed to the outermost two of the six lines.

"The meaning of the family, this second line is the top of the canal?"

Seeing that Liu Ying nodded, Yangcheng Yanyou pointed to the second line on the top and the second straight line on the bottom.

"This, for the bottom of the ditch?"

After Liu Ying nodded again, Yang Chengyan looked at the innermost two lines, and there was a little doubt on his face.

Seeing this, Liu Ying couldn't help but chuckle and leaned over, and pointed to a mark between the two lines.

Looking at the marker, Yang Chengyan's gaze finally appeared a little clear.

"Wide ······"

Jiuzhang, isn't it the bottom width that Zheng Guoqu should have?

I saw Yang Chengyan raise his head thoughtfully and look at Liu Ying with a little uncertainty.

"The meaning of the home, the river section of one hundred and ten miles downstream, the bottom of the ditch is not all dug, only nine zhang of the ditch is dug?"

Hearing this, Liu Ying finally smiled and nodded.

"The bottom of the Zhengguo Canal was supposed to be nine zhang, but now, it has been widened to fifteen or six zhang for the local people and the people."

"If the width of fifteen or six zhang is dug up, the sediment dug from the bottom of the ditch should be thrown out of the ditch by forced labor, and it will be a waste of manpower."

"However, if only nine zhang of the ditch is dug up, the excavated soil should not be out of the ditch, but filled in the remaining six or seven zhang on the side of the ditch?"

"—One, you can dig the bottom of the ditch six or seven zhang wide;"

"In both cases, the soil excavated at the bottom of the ditch does not have to be thrown out of the ditch, and the labor can be saved to complete the work quickly."

Saying that, Liu Ying couldn't help but smile.

"After the winter solstice, the width of the Zhengguo Canal should be reduced by filling the soil; Today, only dig the soil of nine zhang in the ditch, to fill the six or seven zhang of the side of the ditch, and reduce the width of the Zhengguo canal in the future, which can also save a lot of effort. ”

Hearing Liu Ying's description, Yang Chengyan groaned for a while, and restored the picture described by Liu Ying in his mind.

The canal land with a width of 15 zhang from north to south, the north three zhang and the south three zhang are left alone, and only the middle nine zhang is dug out, that is, in the future, it will become the nine zhang at the bottom of the actual canal of Zhengguo Canal.

And from this nine-zhang wide canal, dig one foot to one zhang and three feet deep, and throw the excavated soil directly to both sides, that is, the bottom of the ditch in the north and south three zhang without digging.

In this way, the ditch that was originally to be dug 15 zhang wide was reduced to 9 zhang wide; The silt, which was supposed to be transported from the bottom of the canal, has also been turned into soil for filling and widening on the side of the canal······

"If it weren't for the fact that the Zhijia had never been in charge of water conservancy affairs, the minister would not have thought that the person in front of him at this time was a well-known water engineer in the world!"

Seeing that Yang Chengyan was full of joy and said this admiration, Liu Ying only smiled shyly and nodded to Yang Chengyan.

"Even Shaofu also thinks that there is nothing wrong with this law, so let's act according to this repair."

7017k