Expressway projects under 'double' pressure

Many large-scale expressway projects being implemented simultaneously in the Mekong Delta are causing the demand for soil, rock, and sand to increase dramatically, causing difficulties for investors, construction units, and localities. Investors and contractors are under “double” pressure on progress and construction material sources, especially sand for foundation.

The progress of the Hau Giang - Ca Mau expressway embankment has only reached 11.8% due to a shortage of sand. Photo: Huynh Anh/VNA

"Hung" due to lack of sand

According to the report of the Ministry of Transport , the Mekong Delta is currently implementing 4 expressway projects including: Can Tho - Ca Mau, Chau Doc - Can Tho - Soc Trang, Cao Lanh - An Huu, My An - Cao Lanh with a total length of 355 km, the demand for sand for embankment is about 53.68 million m3. However, the supply of this material is still slow, not meeting the progress.

The Can Tho - Ca Mau expressway project, nearly 110 km long, is part of the North - South expressway in the East, and was started in early 2023. Most of the project passes through rice fields, canals, and rivers, which are areas with weak geology and require a lot of sand for foundation.

Mr. Tran Van Thi, Director of My Thuan Project Management Board, investor of Can Tho - Ca Mau project, informed that the total demand for sand for the entire project is 18.5 million m3; in 2023 alone, it is 9.1 million m3, supplied from sand mines in An Giang, Dong Thap, Vinh Long provinces, but so far, contractors have only received about 0.48 million m3. Therefore, after 9 months of implementation, Can Tho - Ca Mau expressway has only achieved 9% of the contract value, 3 months behind schedule.

For the Chau Doc-Can Tho-Soc Trang expressway project, which is over 188 km long and started construction last June, it is estimated that the project will need about 29.73 million m3 of road sand; about 0.99 million m3 of construction sand; and about 4.48 million m3 of various types of construction stones.

Following the Prime Minister's direction, An Giang province agreed to support about 7.5 million cubic meters of sand from the sand mine on Tien River in Binh Phuoc Xuan commune and Cu Lao Tay branch (Cho Moi district) for this project. However, this is a river branch belonging to the national inland waterway, not a sand mineral mine, so it is currently entangled in legal issues and cannot be exploited yet.

In addition, sand resources in An Giang province are also lacking because many projects are being implemented at the same time, so reserves are affected. Therefore, after more than 3 months of implementation, the Chau Doc - Can Tho - Soc Trang expressway is still at a standstill due to lack of sand for embankment.

In Dong Thap, although the amount of sand supplied for highway projects is basically met, the locality is still concerned about the mechanism for handing over mines to contractors for exploitation, especially in terms of control.

At a recent working session with Deputy Prime Minister Tran Hong Ha, localities in the Mekong Delta region pointed out the reasons leading to the shortage of sand supply, even though the sand reserves are nearly 2.2 times higher than the demand of key transport projects.

According to the leader of the An Giang Provincial People's Committee, the Ministry of Natural Resources and Environment has provided guidance on the application of the special mechanism, but many contents are unclear. Or, each province has an inconsistent understanding when going into details of each step and procedure, so there is confusion in implementing the mining licensing procedure through the above special mechanism.

In addition, during the working sessions, Deputy Prime Minister Tran Hong Ha requested to simplify procedures and immediately increase the capacity of sand mines in operation by 50%. At the same time, re-issue mining licenses for expired mines; put into operation new mines specifically serving expressway projects on the basis of strict environmental monitoring and supervision.... However, with a series of sand mines being "caught" by inspectors and the increasingly serious landslide situation, many mines are "afraid" to exploit.

Major General Nguyen Huu Ngoc, Commander of the 12th Corps, Chairman of the Board of Members and General Director of Truong Son Construction Corporation - the leading contractor of the Can Tho - Hau Giang Expressway, said that the project's progress is being affected by difficulties in the supply of sand materials for embankment and if there is no timely source of embankment soil, it will be impossible to fill the weak soil on the route. Thus, the project will be difficult to reach the finish line in 2025 and put into operation in early 2026 as directed by the Government.

Clearing material sources

To solve the problem of sand supply and meet the progress of highway projects, localities in the Mekong Delta proposed to establish an interdisciplinary team to remove obstacles in mechanisms, policies, legal status, and procedures for sand exploitation in each phase, ensuring sufficient sand sources for highway construction according to the approved schedule.

Identifying the current common difficulties related to procedures for opening new mines, transport experts said that ministries and branches need to soon review and provide guidance for general application to localities in accordance with regulations. Especially regarding environmental impact assessment procedures for mines implemented under special mechanisms.

Proposing solutions to overcome difficulties in supplying sand materials for key projects in the Mekong Delta, experts said that the amount of sand in the sandbanks and alluvial flats is relatively large and can be exploited to serve the construction of landfills. Therefore, the inter-sectoral ministries need to consider whether or not to dredge sand at these locations. If possible, develop a sequence of dredging steps, regulate the flow, specify which sandbanks and alluvial flats are kept and where dredging is allowed, and how much dredging is needed to limit landslides.

Professor, Doctor of Science Nguyen Ngoc Tran, former Vice Chairman of the State Committee for Science and Technology, former Vice Chairman of the National Assembly's Committee for Foreign Affairs, said that the exploitation of sand from dredging to serve the construction of expressways will aggravate landslides and coastal erosion. Therefore, it is necessary to soon issue the Vietnamese Standards for Ultra High Performance Concrete (UHPC), applied to the construction of expressways on viaducts. Choosing expressways on viaducts helps to solve many challenges at the same time: sand scarcity, less harsh impact on nature, no flood prevention, no fragmentation of landscape, livelihoods and society, economic superiority, long-term use...

Faced with the above situation, on September 12, the Prime Minister issued Official Dispatch No. 794/CD-TTg on urgently developing standards for expressways and focusing on implementing solutions to ensure the progress and quality of transport infrastructure investment projects.

Notably, in this dispatch, the Prime Minister assigned the Ministry of Transport to preside over and coordinate with the Ministry of Natural Resources and Environment, the Ministry of Construction, the Ministry of Agriculture and Rural Development, and the Ministry of Science and Technology to accelerate research on the use of sea sand for foundation construction of infrastructure projects to reduce dependence on river sand. At the same time, proactively source materials and speed up the construction progress of projects in the coming time. The use of sea sand must ensure technical standards and not cause negative impacts on the environment.

Good news for key expressway projects in the Mekong Delta, the Ministry of Transport announced that it has completed a pilot test of sea sand used to build roadbeds for transport infrastructure projects in this region. Through testing, the pilot sand sample at the restoration section of Provincial Road 978 under the Hau Giang - Ca Mau project has met the physical and mechanical standards.

Regarding chemistry, the Ministry of Transport said it has tested the salinity content and brought it to the construction site, installed samples to monitor groundwater and surface water during construction. So far, the Ministry has taken samples three times, the results are similar to river sand. The Ministry of Transport is requesting continued environmental monitoring from now until the end of the year to review the results. If the requirements are met, this will be an effective alternative source of materials, contributing to solving difficulties in sand supply, helping to promote the completion of key projects in the Mekong Delta.

However, the Ministry of Transport emphasized: “It will take until the end of 2023 at the earliest to determine the ability to meet the technical requirements of sea sand used as filling material for projects. Therefore, in the immediate future, in 2023 and 2024, the source of filling material for projects will mainly be river sand.”

Mr. Nguyen Van Nguyen, Deputy Director of the Vietnam Geological Survey, acknowledged: For the need to make filling materials, both sea sand and river sand can be used. However, for the need to make construction aggregates (mortar and concrete), the use of sea sand must be studied at each mine to propose a treatment solution that meets the requirements of aggregates stated in national standards.

( According to https://baotintuc.vn/kinh-te/du-an-duong-bo-cao-toc-truoc-ap-luc-kep-20231003062507861.htm )

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