Strictly manage water resources to ensure irrigation for crops in the An Trach system.

According to the April 10 bulletin of the Central and Central Highlands Institute of Water Resources (under the Vietnam Institute of Water Resources) on monitoring and forecasting water quality in the An Trach irrigation system, serving agricultural production in Quang Nam and Da Nang City, from April 4 to 9, in Quang Nam province, the water level at Bau Nit dam fluctuated from 1.9 - 2.15m; Thanh Quyt dam fluctuated from 2.05 - 2.48m; Ai Nghia hydrological station fluctuated from 2.44 - 2.77m. Regarding salinity, the monitoring points on the Thu Bon River branch (old Cau Lau bridge, Cam Dong arch) and the Vinh Dien River branch (pumping stations) were not affected by salinity.

Taking samples for water quality analysis at Tu Cau Pumping Station of An Trach irrigation system. Photo: PV.

In Da Nang City, the water level at An Trach dam fluctuates from 1.57 - 2.4m, and on April 6, the water level was lower than the prescribed level (only reaching 1.57m). Regarding salinity, on the Vu Gia river branch, the salinity is low, and the Tuy Loan and Mieu Ong pumping stations have not been affected by salinity.

However, last week, the salinity at the upstream of Cau Do water plant tended to increase compared to the previous week, ranging from 0.028‰ - 0.649‰, at some times the salinity at this location exceeded 0.1 - 1.6 times the allowable limit for domestic water supply.

The Central and Central Highlands Institute of Water Resources calculates that next week (from April 11 to 17), the indicators at 6 water quality monitoring locations will all meet the requirements for agricultural irrigation water quality, the salinity at the locations will increase slightly compared to last week, especially at the upstream location of Cau Do, the highest salinity can reach 0.81‰. Therefore, during the operation of the An Trach irrigation system, relevant units need to pay attention to:

- The Department of Agriculture and Environment of Quang Nam province and Da Nang city need to pay attention to directing the Irrigation Sub-Department and the Irrigation Exploitation Company to continue monitoring meteorological and hydrological forecast information and developments of saline intrusion and water quality to proactively adjust timely and effective response solutions to supply water for winter-spring crops.

Staff of the Central and Central Highlands Institute of Water Resources Science take samples to analyze water quality in the An Trach irrigation system. Photo: PV.

- Da Nang City and Quang Nam Province Irrigation Exploitation Company Limited need to strictly manage water resources and ensure irrigation for areas in the system; direct units to monitor water level developments, closely follow tide schedules, water discharge schedules of hydropower plants as well as saline intrusion developments to develop operational plans to ensure safe water supply for the winter-spring crop.

In addition, units need to closely coordinate with water cooperative organizations to strengthen field inspection and regulate water flow on irrigation canal systems to provide timely water for production.

The salinity forecast at Cau Do location from April 11 to 17 is likely to fluctuate from 0.02‰ to 0.81‰, at some times exceeding 0.25‰ (250mg/l). Therefore, it is recommended that Cau Do water plant monitor the salinity changes at this location to have an operational plan according to regulations. At times when the salinity is in the range of 200÷1000mg/l (0.2‰ ÷1.0‰), it is necessary to adjust the flow through the water intake of the plant and take the maximum possible water from Vu Gia river from the pumping station at An Trach dam. At the same time, proactively develop reasonable operational plans to ensure safe water supply next week.

In addition, reservoir owners operating hydropower plants need to comply with the inter-reservoir operation process in the Vu Gia - Thu Bon river basin approved by the Prime Minister and Article 28 of the Law on Water Resources to support the work of preventing drought and saline intrusion in downstream areas. At the same time, closely coordinate with the Department of Agriculture and Environment of Quang Nam to develop and agree on a plan to release water for power generation in batches associated with the water demand for domestic use and agricultural production in the winter-spring crop of 2024 - 2025 in the downstream area, ensuring efficient water use.

Source: https://nongnghiep.vn/quan-ly-chat-nguon-nuoc-dam-bao-tuoi-cho-cay-trong-tren-he-thong-an-trach-d747525.html