Cho Moi district has installed landslide warning signs, barricades to prevent people and vehicles from entering the area at risk of landslides. (Photo: Thanh Sang/VNA) On the afternoon of June 15, information from the People’s Committee of An Giang province said that the Chairman of the Provincial People’s Committee Nguyen Thanh Binh signed Decision No. 1289/QD-UBND declaring an emergency situation of landslide on the banks of Rach Ong Chuong section. km16+250-km16+300, Provincial Road 946 in Cho Moi district. Before that, around 8:30 a.m. on June 8 at the area Km16+250, near Xa Mach bridge, Provincial Road 946 (Cho Moi district, An Giang province) a landslide occurred on the banks of the Ong Chuong river with a length of about 50m and 2m deep into the roadbed. The landslide has completely collapsed the roof of the roadbed and is in danger of spreading, affecting traffic safety. According to Decision 1289, the People’s Committee of An Giang province requested the Department of Natural Resources and Environment of the province to zone areas at risk of particularly dangerous landslides, to put up signs of particularly dangerous landslides, to set up safety corridors. safety and organize the monitoring and monitoring of landslides, timely report proposals to the Provincial People’s Committee. In particular, the People’s Committee of Cho Moi district is responsible for monitoring landslides, promptly handling the relocation of people and properties out of areas at risk of particularly dangerous landslides; notify and put up landslide warning signs, barricades to prevent people and vehicles from entering areas at risk of landslides; coordinate with units to arrange guard forces to closely monitor landslide developments and maintain security and order in the area. The Provincial People’s Committee also requested the Provincial Department of Transport to coordinate with the Provincial Police and relevant units to organize the channeling and regulation of waterway and road traffic through the landslide area. The Provincial People’s Committee assigned the Department of Transport to urgently select a qualified and experienced consulting unit and construction contractor, and organize the formulation of urgent handling plans; mobilize forces and materials for urgent handling in accordance with law. Relating to the landslide area Ong Chuong canal , section Km16+250-Km16+300 on Provincial Road 946, before that An Giang Department of Transport also announced to limit the load and regulate traffic for all kinds of vehicles that need to circulate on the route. Provincial road 946 and Ong Chuong river from 14:00 on 11/6. Accordingly, only two-wheeled vehicles and rudimentary vehicles are allowed to pass through the landslide area. The remaining means of transport when wishing to go from Long Xuyen city to Cho Moi and other nearby localities or vice versa, they need to move in the direction of Provincial Road 944 and Provincial Road 942. Load capacity of less than 100 tons is circulated on the Ong Chuong river route. The landslide on the north bank of Cai San canal affects people’s traffic. (Photo: Thanh Sang/VNA) On the morning of June 15, the North bank of Cai San canal at Thoi Thanh hamlet, My Thanh ward, Long Xuyen city, An Giang province also had a serious landslide, affecting traffic in the area. The landslide section has a length of about 10m, a width of 2m, located at the end of the embankment route, built by the Construction Investment Project Management Board of Agriculture and Rural Development in An Giang province in 2019-2020. The location of the landslide threatens the traffic route in the area. Mr. Luong Huy Khanh, Chief of the Standing Office of the Steering Committee to Respond to Climate Change – Disaster Prevention and Control and Search and Rescue in An Giang Province, said that the cause of the landslide north bank of Cai San canal was initially determined. determined due to the influence of the flow of the curved river, eddy water, and the impact of water transport. “After the North bank of Cai San canal was eroded, the Steering Committee for Climate Change Response – Natural Disaster Prevention and Control and Search and Rescue in My Thanh Ward, Long Xuyen City, coordinated with local people to cooperate with the local people. install barriers at the landslide location, reduce traffic loads, hang warning signs, install warning lights,” added Mr. Khanh. Cai San canal, the section from Nam Su canal to Sau Ba canal, My Thanh ward, Long Xuyen city, was assessed by An Giang province as being particularly dangerous, causing direct danger to residential areas. concentrate. From 2019 to present, Cai San canal The section from Nam Su canal to Sau Ba ditch has 4 subsidence events, serious landslide . An Giang province has determined the cause of Cai San canal landslide due to the area located on the bend, strong current pressure close to the shore in the pouring season. In addition, due to the opposite bank in Thot Not district, Can Tho city, where there are many milling factories with many waterway vehicles circulating, turning around, causing the water current to slam on the shore of An Giang, causing landslide. In the past time, the People’s Committee of An Giang province has invested in building embankments to urgently overcome landslides of Cai San canal from Nam Su canal to Sau Ba canal, in order to stabilize the shoreline, ensure waterway traffic and ensure traffic safety. The road is convenient, gradually stabilizing life, helping people feel secure to develop production, contributing to the development of the local economy…/.

As recorded, late on the night of April 23, after a long heavy rain, a series of areas in Mui Ne ward (Phan Thiet city) and Hoa Thang commune (Bac Binh district, Binh Thuan province) had a sand spill incident. , many serious places, causing traffic jams for many hours. Sand floods made the land of Doc Mo (Hoa Thang commune, Bac Binh district, Binh Thuan province) torn apart. In which, the area most affected is route 716 (the Doc Ma section, Hoa Thang commune, Bac Binh district). According to local people, at the time of the heavy rain, sand and water from the hillside collapsed onto Road 716, causing serious congestion, a series of vehicles could not move. Due to the large amount of sand and water pouring down, the land on the road 716 was torn apart, forming a trench nearly 20 meters deep, hundreds of meters long running straight to the sea. By the morning of April 24, vehicles were able to pass through the 716 road area of ​​Bac Binh district By the morning of April 24, the amount of sand and water that had drifted along this trench poured straight into the sea so the means of transport were able to move normally. Also on the coastal road in Mui Ne ward (Phan Thiet city), a series of places similar sand spill phenomenon occurs, causing traffic to be affected. In the area before the real estate project Apec Mandala Wyndham Mui Ne, the overflowing sand covered a section of the road As observed, in the area in front of real estate projects Sunny Villa and Apec Mandala Wyndham Mui Ne, sand overflowed to cover a section of the road. Currently, these project owners are sending manpower and means to clean up the consequences. In particular, also on the night of April 23, at the GoldSand Hill Villa real estate project, the phenomenon of sand overflowing continued to make it difficult for many vehicles to travel. Before that, late at night on April 20, after a heavy rain, there was a serious sand spillage phenomenon, causing many vehicles to be buried, many restaurants and people’s houses were affected. Also on the night of April 23, in the face of complicated heavy rains, there was a risk of sand spillage, Mr. Nguyen Van Phong, Vice Chairman of Binh Thuan Provincial People’s Committee and the delegation checked and suggested Stakeholders take measures to ensure safety, prevent landslides, overflowing sand, affecting people’s lives. Late April 23rd, at GoldSand Hill Villa real estate project, the phenomenon of sand overflowed, making many vehicles difficult to pass by. Along with that, after the sand spill incident at the GoldSand Hill Villa real estate project, the Chairman of Binh Thuan Provincial People’s Committee issued a document to direct the concerned departments to completely resolve the situation. Binh Thuan Provincial People’s Committee assigns the Department of Construction to coordinate with relevant units to organize a physical inspection of the project area, compare all design documents, construction permits, construction items, verify cause of landslides, sand; review all project documents, request the project owner to immediately remove the recovered sand from the project, to avoid similar landslides when the rainy season is coming. In the coming rainy season, if the authorities and real estate developers do not have solutions to prevent sand spills, the problems will likely continue to occur.

“Trees soaked in water for 20 days cannot survive,” said landscape planner Ngo Anh Dao, who has planted dull forests along the 650m long shore of Triem Tay and neighboring Cam Kim commune since 2018. Sad is sad, she said, but this is the law of nature.

The cork tree is the body

According to TS. Ngo Anh Dao is “a pioneer tree and a sacrifice for the posterior generation behind.” As a result, although the number of poor trees is only 1/3, the riverbank of Trem Tay village does not erode like in the previous years when floods came.

This poor forest is the outermost layer of an ecological soft embankment coping with landslide. Anh Dao put it to the test at her farm An Nhien after the historic flood in 2017 seeped 12ha of the riverbank area. Before the embankment was constructed, each time the flood came, the banks of the Trem Tay River would recede more than ten meters deep and many villagers determined that they would have to leave sooner or later.

TS. Ngo Anh Dao, the concept designer of the ecological embankment. Photo: Yen Duong

The ecological soft embankment model is the result of many years of observation and research by TS. Anh Dao goes downstream of Thu Bon river. She does not consider this as a new invention but simply a process of restoring indigenous ecosystems.

“This is a very sensitive and fragile area,” said the female landscape planner, when she was under pressure from the water pouring in from the Truong Son mountain range, and the pressure from waves and storms. Just comparing the map of Thu Bon river basin from 1984 with the present, anyone can recognize the appearance, swelling and disappearance of floating dunes. If more than 30 years ago, there were four large and small sand dunes in front of Trem Tay, over time, the side of the mudslide, now they have formed a large dune deviating to the north, causing the flow from upstream to crash into the bank of Trem Tay village and the neighboring Cam Kim commune. Therefore, every time the flood comes, the Trem Tay bank will slide and the other sand dune bank accretes.

The villagers of Trem Tay seem to be too familiar with this harsh law of nature. At the age of 54, Pham Duoc had to move his house twice despite being born and raised in this village. His first home was at the head of the village but by the age of twenty, he was forced to move to the middle of the village. In 2009, the commune authorities urged him to continue to move, but because of “comfortable housing, a garden, a chicken”, he decided to stay. However, after the historic flood in 2017, when the water flooded to 1.6 meters deep, he got scared and decided to demolish the house, sell the land and move to his current home at the end of the village.

“I wanted to build a house to leave for the children, so I accepted it,” he was told. Each time like that, he “is not sad” because “has to accept it.”

Also because of the desire to keep the village and have a passion for planting trees, this builder began to work as TS’s farm housekeeper. Anh Dao from 2016 on a piece of land at the end of the village abandoned because some people have retreated inland like Mr. Can. Others, especially the young, have quit farming because their rice land is either no longer available or salty, and go to work on tourism in Hoi An or Da Nang.

On this wasteland, Mr. Can and other workers have built wooden houses with modern designs, combining the high structure of stilt houses with indigenous materials such as bamboo and grass. The houses are mixed with nursery gardens and research of diversity of plants.

Standing from the house overlooking the river bank is a bamboo forest that villagers planted in the 1980s to prevent floods. “Thanks to this bamboo forest, when the flood comes, the flow will decrease”, he is explained. “Like when water runs through that basket.”

In front of the bamboo forest, along the riverbank is the ecological embankment.

Use “soft” against “hard”

Different from the commonly applied concrete hard revetment in Vietnam, the soft revetment does not resist the destruction of waves and floods but backs and accepts it – more similar to the village motto of living with floods. This 200 years old.

“The current popular philosophy is that people are fighting against nature, conquering nature with hard solutions and ignoring the understanding of coastal ecosystems, the access between water and land”, PhD. Mr. Dao analyzed. “Thinking like conquering nature, using it hard against the power of nature will be terrible because its destructive power will be even greater.”

Principle TS. Cherry mentioned that the law is immutable in physics: punching a wall with your hand will always hurt more if you punch the mattress with the same force. And given the increasing intensity and destructive power of storms and floods due to the effects of climate change, new coping measures are becoming more and more imperative to minimize damage from dike breaks.

Illustration of three-layer ecological soft embankment used to cope with the landslide of TS. Ngo Anh Dao. Illustration: lambinh

In the design of the ecological embankment, the cork tree is TS. Cherry brought back to plant from Quang Tri, is the outer layer of the buffer protecting the village shore. The roots of this plant are of two types. The main root is poked straight down, possibly up to ten meters deep. The secondary roots, also known as lung roots, are precipitated when immature, soft and swaying with the waves. When the tree grows, this lung root hardens, protrudes from the mud about 60-80cm, very hard. Therefore, cork trees have the ability to accumulate mud, hold soil, and reduce the destructive power of underground waves.

Next to the cork layer is a layer of grass, including native grasses such as hammer grass, grass with bald roots that can be up to 3m deep below the ground, next to the pangasius is a two-leafed tree, the roots are even deeper. tens of meters. These are easy-to-live, fast-growing plants with good soil holding capacity.

The last layer is a row of casuarina trees planted from 2017 that are 8m high. In addition to the ability to hold soil, the height and softness of the conifers help to both block waves and windbreak.

These three layers together create a green vegetation reinforced with bamboo biological “lock” layers to support soil retention in the early years when the layers are young, the roots are not deep enough.

With the initial results achieved, TS. Anh Dao is confident that the philosophy behind this model is the right direction for the sensitive downstream areas that are suffering from both natural disasters and natural disasters. The flood discharge of dozens of hydroelectricity upstream; exploitation of sand in the river bed; monoculture agriculture, improper exploitation of groundwater, causing subsidence; along with tourism development, regardless of the fragility of the ground here, all contribute to increasing the risk of landslides in the area, he explained.

Natural balance

Realizing the initial efficiency of the project, in addition to the affordable price – the construction cost of 1 meter of ecological embankment is only 1/5 of the cost of building the concrete embankment – Hoi An government plans to extend 900m of longitudinal embankment. According to the territory of Phuoc Thang village in the neighboring Cam Kim commune, where after the flood in 2017, the bank fell 50 meters deep into the mainland.

However, the ecological embankment is not without its risks. “An embankment requires a tree to develop to a certain extent to be effective,” said Nguyen The Hung, vice president of Hoi An city. This is a fact to consider when choosing the time to start planting trees for ecological embankments because according to the experience of the Hoi An people, every three to five years a big flood will repeat and the poor forest also needs that many years. to be able to cope with floods.

The most obvious evidence is the initial failures in the construction of ecological embankments by TS. Cherry. In fact, the horticultural forest she planted in 2018 was the second test after the failure of 2017, when the historic flood hit and killed the immature cork trees that were only one year old.

Pham Duoc, born and raised in the village of Trem Tay, had to move his house due to the impact of floods and landslides. Photo taken on January 26, 2121 in Trem Tay village (Dien Phuong, Dien Ban district, Quang Nam province). Photo: Yen Duong

Therefore, each ecological embankment requires a deep understanding of the local soil and climate. Invited by the authorities of Dak Nong and Dak Lak to study the replication of an ecological embankment model for the Krong No riverbank, which is suffering from severe landslides, PhD. Anh Dao cannot carry the whole model from An Nhien. The key thing that does not change is the principle of using measures of “soft, back and forth” instead of “forward and conquer”.

Post-flood cleaning in An Nhien continues after Tet. Meanwhile, the poor forest has begun to show signs of revitalization. “Maybe I will leave it alone, the cork tree will grow back on its own, or I will plant more, depending on the budget”. Anh Dao said.

What is important according to the doctor is the long-term perspective. Once the embankment ecosystem is returned to its natural equilibrium, other social and economic benefits will follow.

Since the ecological embankment, shrimp, fish, birds, wild ducks, many insects have created a new source of livelihood for the village. Each spring, “so many birds can not sleep at night,” he shared. The green embankment on the transparent river also contributes to attracting more tourists to visit this ancient village.

If before 2015, Trem Tay land was sold for 1 million / m2, not many people bought, now, the land price has increased 15 times thanks to community tourism projects, resorts and the belief that village land will is kept. Walking around the road surrounded by the tea tree fence of the village, you can see that people are taking advantage of repairing and repainting their houses to make them more stable and spacious. From the past two years, young people working away from home have come back with plans to do tourism and open shops. All just wait for the disease to pass to be ready to revive.

Le Giang Lam

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(This article is supported by the Rainforest Press Foundation in partnership with Pulitzer Center)