More than 1,000 cavalry of the Matsue Army ravaged the rear hinterland, and the news soon reached the Koi Castle on the front line, and then from this bridgehead to the north, it was sent to the garrison of the army outside the fortress of Nanfeng. {We don't write novels, we're just web text porters-,

The anger of Omani Wenwu and Qianyuanji does not need to be described in too many words. All you need to know is that Saladin has broken a whole set of celadon tea sets that he treasures, and you can know how out of shape he really is. Wei Chiming, while secretly proud of his foresight, couldn't help but be annoyed that the Songjiang Army had a tricky vision and actually landed in a place that he had not expected at all.

At the moment, the most serious situation for the Omani Northern Expedition has emerged - an embarrassing situation that they had hoped to play out in the rear of the enemy, but it turned out to be for themselves.

Whether or not to send a large army back to help has become a heavy and unspeakable topic, but they cannot avoid it.

To mobilize an army to encircle the cavalry, it often requires many times the strength of the enemy. As far as the current situation is concerned, it can almost be seen as giving up the idea of continuing the offensive. Saladin had been hesitant to withdraw his troops before, and now the bad news undoubtedly shook his heart even more.

Considering that the Matsue cavalry was causing more damage with each passing day, they had to make a decision as best they could.

However, Saladin never imagined that the real bad news was yet to come.

Just attacking and burning some villages and towns is not enough to really shake the morale of Oman's army. The cavalry of the Songjiang Army, which had landed across the sea for thousands of miles, was by no means satisfied with just doing such a trivial matter.

Dayuan River!

It is an important river on the Chiang Mai Plain, with a total length of more than 800 li, irrigating hundreds of thousands of acres of fields along the lower river, and indirectly feeding nearly one-eighth of the population of the Chiang Mai Plain. This is clear to all the Omanis and even many of the Empire, but few are aware of it. Where does the water of the Dayuan River come from?

If someone explores the source and travels north along the Dayuan River to the southwest uplift of the Chiang Mai Plain, they will find that this is a cluster of thousands of mountains with steep terrain, the tail end of the southern side of the Bayan Mountains, and the Tsing Yi River with turbulent water flow on it. A large amount of gravel and sediment washed down by the Tsing Yi River. After the sudden flow into the flat Chiang Mai Plain and the Dayuan River, siltation and congestion are prone to occur.

Whenever the upstream rains flood, the Dayuan River is often flooded or even diverted.

The seventh emperor of the Hue Dynasty, the grandfather of the declining prince Nguyen Thi Minh, requisitioned a large number of laborers to build the famous flying sand weir in the upper reaches of the Dayuan River to regulate water conservancy. Since then, the flooding of the Chiang Mai Plain has been greatly reduced. To this day, the Omanis still use this hydraulic project of the previous dynasty. And regular maintenance every few years.

That's right, one of the most important purposes of this cavalry, which penetrated deep into the rear of the enemy, was to destroy the flying sand weir. Although the rainy season has long passed, the abundant precipitation in the Tsing Yi River basin this summer still makes the water level of the Dayuan River and Feishayan very high. Had it not been for the unexpected delay in the landing of the Omani Guards, it would have been possible to catch the last train of an autumn flood. The effect will definitely be much worse now, but digging the Feishayan dam and releasing water into the lower reaches of the Dayuan River can still cause a man-made catastrophe.

Hundreds of thousands, hundreds of thousands, hundreds of thousands. will be implicated in this!

At the peak of the rainy season, that number could have multiplied five or ten times!

Of course. Although it is true that the excavation of civil water conservancy can be an immediate blow to the establishment of the Oman, it is too hurtful to be brought to the table. Even, even the cavalry of the Songjiang Army, which secretly carried out this matter, only had more than a hundred horsemen. Led by a captain who had lived in the Kingdom of Oman for several years, he also deliberately concealed the power of Nguyen Shi Minh's faction.

Both the MI and Tran Vu were suspicious that the legitimate remnants of the Hue dynasty would oppose or even hinder the operation, even if it was for the purpose of fighting the Omanis. But after repeated deliberations, Chen Wu still made up his mind.

Reasons are other. There is no much mercy to talk about in war!

After the Omanis occupied the Nanfeng Mansion in Tiannan, didn't they also wantonly forcibly recruit the people to demolish the Nanfeng fortress and build the tombs of the fallen soldiers for them? What's more, when Chen Wu started his business, he drove the displaced people to attack Wu'an, which was actually no different from this. If it was said that he died just because he didn't have soldiers, and he still had a way to survive by relying on his experience before crossing the army, then after he went all the way to the three counties, he had no way to retreat, and could only compete for that position either voluntarily or pushed by his subordinates.

In that case, what else is there to do in order to fight these aliens?

After all, Feishayan has been established for a long time, and it is normal for it to collapse due to its disrepair and heavy rain upstream. As long as you don't fall into the trap, even if someone guesses anything afterwards, it won't help.

As the plan had been drawn up for a long time to be executed, hundreds of specially selected cavalrymen, shortly after the capture of Nahar, quietly broke away from the brigade one night. By the time more than 1,000 of their comrades had conquered the north and south to attract all the attention of the Omanis, they had already set out on their way with enough food and necessary tools.

Speaking of which, it may seem easy to sneak into an enemy country and dig a dike, but it's really hard to do. In the case of a battle against the Imperials on the front line, the hundred or so riders themselves are easily noticeable. How to arrive near the Feishawei without suspicion is directly related to the success or failure of the entire operation.

For this, these cavalrymen had to be camouflaged.

The military robes they wore were all those of the Kingdom of Oman, and they held official documents forged by the Military Intelligence Service. Most of these selected cavalrymen also had some knowledge of the Omanis. Unless you happen to bump into the black-clothed guard who is engaged in intelligence, it is difficult to tell.

As for the route of travel, this is not a problem, as long as you go upstream along the Dayuan River, you will definitely not get lost.

Travel day and night, avoiding crowded roads as much as possible. After suffering unimaginablely, I finally arrived at Minshan, where the flying sand weir is located. Because this large-scale water conservancy project was presided over by the former Hue Dynasty, and since it has been for many years, the Kingdom of Oman has not paid much attention to this place, and they did not think that there would be enemies who would sneak in here to cause sabotage. Only the local government and the nearest villagers each sent a team of people here to monitor the water situation.

Easily caught two local mountain people, and in the name of the Omani official cavalry, he easily asked what they wanted.

After the extermination, the cavalry quickly moved into action, killed the villagers patrolling the area, and then began digging the embankment.

In order to confuse the enemy as much as possible, they also left a few ornaments of the desert peoples in the Western Desert nearby. It was an officer of the Military Intelligence Department, and after getting Chen Wu's order, he finally got it from a few big businessmen in Ninghai County who liked to collect. Anyway, at the beginning of the year, the Omanis clashed with the desert people over the gold mines, and they were retaliated against by thousands of people.

If Qianyuanji hadn't investigated the collapse of the Feishaweir, it would have been the best. If someone investigates and follows the clues to find these ornaments, it can also have some misleading effect. As for whether Qianyuanji would believe it, and how the people in the deep desert in the west ran to the Chiang Mai Plain, it was not for the Songjiang army to worry about.

As for how these cavalrymen would return after the collapse of the flying sand weir, Chen Wu also gave a plan.

With the lower reaches of the Dayuan River flooded, it is definitely not possible to go back the way it came. They would head straight north, ninety degrees east from the northwest end of the Red River Valley, and eventually return overland to the South Peak Fortress. At that time, the Omani army under the South Peak Fortress should have left long ago.

In this world, it is always a hundred times easier to destroy than to build.

When the Feisha weir was built, the people of the Hue Dynasty spent unimaginable manpower and material resources, and it took four whole years, or with the help of the terrain, to complete the initial project, not to mention the subsequent expansion and maintenance. But to destroy it, it only takes a few hundred cavalry to dig a slight gap in it. The huge pressure of the water leakage will continue to wash and expand this gap, and eventually the entire flying sand weir will completely collapse!

"I hope Sanqing Daozun won't blame me!"

The cavalry captain, who had read a few Taoist books, looked at the vast flow of the Tsing Yi River on the inside of the Feishaweir, silently muttered a sentence in his heart, ordered his subordinates to dig up the last section, and then fled north like a flying horse.

With a rumbling sound, a flood that would not have occurred rushed from the Dayuan River all the way downstream.

It was the biggest flood in 15 years for the Omanis!

………

The sudden flood in the upper reaches of the Dayuan River displaced hundreds of thousands of people along the 800-mile coast, and there were heavy casualties!

Not only that, due to the high terrain of the Dayuan River, the river water backs up towards the rice fields and canals on both sides, which has a severe impact on the second rice crop of the year in the Chiang Mai Plain. However, in the Dayuan River Basin, the yield will be reduced at the slightest and the harvest will be wiped out at the worst, which will deal a heavy blow to the grain output of the Omanis this year.

Even if the assessment of the entire disaster, reports from various places, etc., have not yet been sent, this news alone is enough to make the Omani civil and military officials outside the South Peak fortress despair.

Two consecutive Tiannan wars consumed a lot of food and wealth. At present, it is very likely that as many as hundreds of thousands of people will be relieved and relieved, and the manpower and material resources consumed are unimaginable. If it is not dealt with in time, and those remnants of Nam Thai and Hue people fan the flames and set off a popular uprising among them, then the territory of the Omani kingdom, which has been difficult to stabilize for more than ten years, will return overnight to the time when the Hue Dynasty was just annexed.

"Damn, it's okay during the rainy season, why is it that after the autumn flood, the Dayuan River has caused a flood!"

Saladin's face was haggard to the extreme, and he looked at the head of the fortress of Nanfeng, which had once climbed but now seemed to be out of reach, and was silent for a long time, and finally gave the order to withdraw again in extreme unwillingness.

Perhaps, from the very beginning, his strategy of plotting against the Qianyuan Empire was wrong! (To be continued.) )