The means of surveying topography were extremely limited at that time. In order to select suitable sites for weirs and embankments in Qingyi Water and Mingxi River, Yu Chengzhen organized dozens of people to survey the topography of a radius of 20 to 30 miles upstream of Qingyi Water and Mingxi River, which cost two days.
More than a month.
If we want to choose a place to cut off the Ru River between Wuyang and Zhaoling and divert the upper reaches of the Ru River into the Ying River, we need to conduct a comprehensive survey of the area from the north bank of the Ru River section between Wuyang and Zhaoling to the south bank of the Ying River.
survey.
This area is narrow from north to south, about 70 to 80 miles in depth, and slightly wider from east to west, about 120 to 30 miles in length. The amount of work required for topographic survey is about ten times that of the upper reaches of Mingxi River and Qingyi River.
Twenty times.
More importantly, in addition to the fact that this area is controlled by the Yue Hailou rebels, there is probably no natural waterway that can divert the Shuishui River into the Yingshui River by intercepting the river. It would take a lot of effort, but it is probably in vain.
As for the Ruishui and Ruishui rivers, they have burst their banks countless times in history. Yu Chengzhen does not remember the historical records of the Ruishui and Ruishui rivers breaking their banks and taking Ying into the Huaihe River; otherwise, things would have been much more convenient.
"..." Xu Huai said with a distant look, "I just suddenly remembered that when I read local chronicles in the past, I heard that there was a place named Xiaoquegang where Wuyang meets Zhaoling in the east. One year, the Shuishui River burst its embankment here and flowed into Ying in the north. I was stunned for a while.
I don’t remember which local chronicle I read this in!”
"Really?" Yu Chengzhen was stunned for a moment and said, "Xu Hou did remember that the Shuishui River burst its embankment at Xiaoquegang and entered Ying? If so, things would be simple!"
Even if Yu Chengzhen had not read the relevant local records, she would not have suspected that Xu Huai was lying.
After all, in today's world, the channels for browsing books are very limited. No one dares to boast that they have read all the books in a narrow field.
"I'm quite impressed..." Xu Huai said without changing his expression.
Xu Huai stood in the wind and rain pavilion, watching the heavy rain before the Nishui River crossing and listening to Yu Chengzhen's introduction to the conditions of Nishui, Ru River and Yingshui. What flashed in his mind was that during the rule of the Central Plains by the Chihu people, they had visited Xiaoquegang in the east of Wuyang.
Memories of intercepting the river and diverting the Nian River into the Ying River.
Although the Shuishui River was artificially dug into the Yingshui River in later generations, the key point is that the Shuishui River has since become the main source of the Yingshui River. It originates from Wufeng Mountain at the southern foot of the Dengjiatai Mountains and passes through the Dengjiatai Mountains and the Jinding Mountain Canyon in the north.
The Xiang River coming out of Suiping has since become the main source of the Ru River.
This shows that there is a long and narrow depression connecting to the Ying River to the north of Xiaoquegang.
Otherwise, with the violent water volume of the Juan River during the flood season, even if it can be intercepted and discharged in Hebei in a short period of time, the original route through Ru River and into the Huai River will be repeatedly recaptured in the future.
"That's easy. I'll take him to Xiaoquegang myself," Yu Chengzhen said. "As long as we have a definite location, we may be able to determine the new Kuanshui river course in a month!"
"Then this matter should be done sooner rather than later!" Shi Zhen, Wang Ju, Su Laochang, Zhou Jing and others accompanied Xu Huai at the Fengyu Pavilion at Shuishui Crossing. When they heard that this matter was feasible, they all wanted to urge Yu Chengzhen to set off to do it immediately.
.
"Wu Chihai, you lead more than a hundred elite cavalry guards to ensure Mr. Yu's personal safety!" Xu Huai ordered Wu Chihai.
Yu Chengzhen made great contributions to the defense construction of Chushan.
If the matter hadn't been urgent, Xu Huai wouldn't have agreed to Yu Chengzhen's personal survey of the terrain near Xiaoquegang.
Near Xiaoquegang
If we can really cut off the river and divert the water into Ying, we must complete this matter before the Zheng family completely withdraws from Heluo.
Because before this, the main force of the captive troops was still contained in Gongxian and Pinglu, unable to take care of Huaishang. Chushan only had to face Yuehailou, and Xu Huai was still confident of temporarily sending troops to occupy the Rushui River section near Xiaoquegang.
, to ensure the success of intercepting the river.
Once this time window is missed and faced with an enemy force several times larger than itself, Chushan will be forced to stick to the city line for a short period of time. If it first ensures the construction of the inner line, how can it be able to intercept the Ru River from the outer line?
After the matter was settled, Yu Chengzhen immediately wrote a handwritten letter in the Wind and Rain Pavilion. In addition to rushing back to Chushan in the heavy rain to gather the necessary manpower, he also led a protection team in Wuchihai and rushed directly to Wuyang City.
To the northeast, Xiaoquegang on the bank of Ru River.
…………
…………
Yu Chengzhen estimated that it would take more than a month to complete the survey of the terrain north of Xiaoquegang, but four days later Liu Qiong'er moved to Ye County to meet Xu Huai, and Yu Chengzhen rushed back to Ye County to see Xu Huai.
Xu Huai took the Ye County government office as his residence and was sitting in the government hall talking to Liu Qiong'er, Su Laochang and Shi Zhen. When he saw Yu Chengzhen, who was covered in mud and water, walked in accompanied by Wu Chihai.
Yu Chengzhen's old, wrinkled, thin face looked full of being deceived.
Xu Huai stood up, personally dragged a chair to ask Yu Chengzhen to sit down, and asked doubtfully: "Mr. Yu, have you seen the terrain to the north of Xiaoquegang so quickly?"
"Can Xuhou still remember in which local chronicle he saw the record that the Ru River burst into Ying at Xiaoquegang? Could it be that he remembered the place name incorrectly?" Yu Chengzhen asked cautiously, "The Ru River was violent and the embankment burst.
, Thirty-four times out of ten, the names of places along the coast have been changed very frequently in history. If Xu Hou can remember more content, I may be able to find a more accurate address by searching the local chronicles!"
"Why, is there any difference between the Xiaoquegang mentioned by Marquis Xu and the current location?" Shi Zhen asked.
"That should be it!" Yu Chengzhen said, "Xiao Que Post is located in the south of the Shuishui River. It is not a big place. It is a low mountain wedged into the river to the north. It is about a hundred feet wide from east to west and extends about four hundred steps from south to south. It is lower in the south and higher in the north.
, there is a dozen-long stone cliff near the water, which is shaped like a bird lying on the waterside, so it is named Xiaoquegang. Looking through local chronicles, the name of Xiaoquegang can be traced back to the Wei and Jin Dynasties..."
"The name of Xiaoquegang can be traced back to the Wei and Jin Dynasties, and it is located at the northeast corner of Wuyang near the Nian River. It is unlikely to change!" Su Laochang asked doubtfully.
"The problem is that there is a long slope on the north bank of Xiaoquegang that blocks the Shuishui River," Yu Chengzhen said. "Except for this long slope, which is more than ten feet high, about twelve miles long from east to west, and two thousand steps wide from north to south, there are thirty or forty meters near Xiaoquegang.
In this section, the north bank of the Juishui River is mostly blocked by rolling hills and mountains, so there is absolutely no possibility of breaching the dike and entering Ying in this section!"
In the past few days, there have been heavy rains on both sides of the Shuishui River, and the Shuishui River is dangerous. After Yu Chengzhen arrived at Xiaoquegang, he also went to the north bank to survey the terrain. The waves were strong, the water was dangerous, and the hills were slippery. Two generals wanted to protect Yu Chengzhen and another craftsman.
He slipped into the turbulent current and was swept away by the dangerous waves, not knowing whether he would live or die.
No matter how high Xu Huai's reputation was in Chushan, Yu Chengzhen was still a little dissatisfied because of his unreliable or even erroneous memory. He worked hard for three or four days in a heavy rainstorm, but two elite soldiers died in vain.
Xu Huai spread the Kan map on the long desk, handed the charcoal to Yu Chengzhen, and said: "Please Mr. Yu, please mark the days of hard work."
It’s on the Kanyu map!”
The current map drawings are actually schematic diagrams, and it is difficult to say whether they are accurate. Even if there is a good map, you need to know the terrain accurately, and you still need on-site surveys.
However, people like Yu Chengzhen have long had concepts such as elevation and slope when surveying terrain.
The Huangyang Lake cofferdam is more than ten miles long. The actual accumulation of earth and stone was compared with the initial topographic survey results. The misunderstanding was finally controlled within one foot. This was a miraculous skill in the world.
Yu Chengzhen took the sweat towel from Liu Qiong'er, wiped the rain off her face, sat on the floor in front of the long desk, and used a charcoal pencil to draw a more accurate outline of the terrain near Xiaoquegang on the Kanyu map.
Although the long slope on the other side of Xiaoquegang has its ups and downs, in this season when the water level of the Shuishui River rises, the lowest gap is more than four feet high from the water level.
In Yu Chengzhen's opinion, it is impossible for the Shuishui River to break through and go northward from here!
The water level of the Juishui River has soared by more than four feet at this location. From Xiaoquegang to the east, Caiying, Xuchen and other places have long since become a vast ocean, so there is no need for the existence of the Yingshui and Rushui rivers.
"The direction of the northern rock cliff of Xiaoquegang is indeed to extend into the Kuanshui River and bend slightly to the west?" Xu Huai asked, looking at the Kanyu map that Yu Chengzhen further accurately sketched, pointing to the long rock cliff of Xiaoquegang.
Xu Huai had walked along Ru River and Ju River twice before, but after all, it was impossible to remember all the details of the coastal terrain clearly. Now he could only ask Yu Chengzhen to confirm this key detail.
"That's true!" Yu Chengzhen said, "Because of this stone cliff, the water flow of the Shui River here in the flood season is extremely dangerous. When we arrived at Xiaoquegang, we didn't find any local people to serve as guides at first. We rashly found a boat to launch the water, and we stopped halfway.
I was overturned by the undercurrent, and if the guards sent by the Marquis had not saved me desperately, I would have been buried in the belly of the fish!"
"There is no doubt that this is the place!" Xu Huai circled Xiaoquegang with a charcoal pen and said to Jiang Xie, who was on duty in the recording office.
An outpost military stronghold. The first priority in selecting the location of the military stronghold is that it can be quickly expanded to a scale of 10,000 soldiers and civilians after the flood season, and there are floating bridges connecting the north and south banks! This order is top secret and is the current top priority of the Wuyang garrison. No delay!"
"It's impossible for the Juishui River to break through the embankment and leak northward from here," Yu Chengzhen said, scratching his head. "What the hell, the Juishui River is restricted by the terrain. Xiaoquegang doesn't even have an artificial river embankment. Did Xu Hou forget it?"
"I must have misremembered," Xu Huai said. "The Shuishui River should not have broken the embankment here, but broken the mountain and flowed northward!"
The flood season of the Juishui River is so violent, but as the main source, the Changru and Ying rivers are extremely stable, and the choice of location for intercepting the river and diverting water is very careful.
The feature of the Xiaoquegang stone cliffs protruding out of the river is actually the function of dikes that block the current and divide the river.
Otherwise, with today's engineering technology, it would be unimaginable to simply use an earth-rock dam to intercept the violent Nishui River during the flood season and tame it and guide it to the Yingshui River.
These terrain details are completely consistent with the memories that flash in my mind.
It is indeed because of the existence of the long slope on the north bank of Xiaoquegang that there is no record of the Huan River diverting the Ying River into the Huai River in history.
What they have to do now is to break through the long slope on the north bank and open a deep canal to divert water...
