Water management with automatic monitoring system

Ninh Thuan is well-known as a “fire basin” because of its hot and dry weather all year round. The province has a low density of rivers and streams due to short and steep terrain. In addition, poor forest vegetation and low rainfall lead to dry season lasting 8-9 months a year. Water shortages and low river and stream flows occur very often.

Meanwhile rainy season is extremely short, lasting only from 3-4 months and the rest of the year is dry season. The annual average rainfall is extremely low, from 700-800mm while the evapotranspiration is very high, averaging from 1,800-1,900mm per year.

Because of extreme weather conditions, the construction of irrigation structures to store water for domestic use, production and other economic activities is required in this arid land. And, in fact, over the years many reservoirs have been built in Ninh Thuan from Central fund.

Ninh Thuan Irrigation Company is now managing 21 large and small reservoirs with a total design capacity of 194 million cubic meters. In addition, the company is operating four spillways including one on Pha river, taking water from Dong Duong hydropower reservoir through Da Nhim power plant.  Currently, the irrigation structures under the management of Ninh Thuan Irrigation Company are able to serve around 27,000 hectares of plants per cropping season in case that the reservoirs ensure water storage capacity.

Le Pham Hoa Binh, Deputy Director in charge of Ninh Thuan Irrigation Company said because of low rainfall and short wet season, in the year with little rain, most of reservoirs are hard to store enough water as designed capacity. For small reservoirs, even with full capacity, they are able to meet the demand for water of one cropping  season  then run out of water. Therefore, to effectively use water resources of the irrigation structures, and at the same time ensure safety for reservoirs in the rainy season, over the years, the company has applied hi-tech solutions in order to increase the efficiency of the management and exploitation of the irrigation structures.

Luu Anh Tuan, Deputy Director of Ninh Thuan Irrigation Company said: Realizing the importance of sciences and technologies, over the years, the company has installed automatic monitoring equipment to measure rainfall and water levels in the reservoirs and spillways to serve the management, operation and coordination of water supplies and disaster prevention in the rainy season. Especially, the rainfall monitoring system in the upstream of the reservoirs is an important tool to help the company make decisions on early flood discharge to cope with floods, reduce inbound water flow, then mitigating damage to the people and property living in the downstream.

Specifically, the company installed automatic water level monitoring system at 13 among 21 reservoirs and all 4 spillways including : Song Sat, Tra Co, Phuoc Trung, Song Trau, Ba Rau, Tan Giang, Song Bieu, Nui Mot, Nuoc Ngot, Thanh Son, Bau Zon, Lanh Ra, Cho Mo and the spillways of Tan My, Song Pha, Nha Trinh and Lam Cam. However, only automatic monitoring system at Song Trau Reservoir is operating stably, providing relatively accurate data.

The water level monitoring equipment at the remaining reservoirs and spillways installed by the Board of building capacity and implementing ODA projects of the water sector are under the process of adjustment. For automatic rainfall measuring stations, currently 8 out of 21 reservoirs have installed including the reservoirs of Song Sat, Tra Co, Phuoc Trung, Song Trau, Tan Giang, Song Bieu, Lanh Ra and Cho Mo.

Along with installing rainfall and water level monitoring stations, Ninh Thuan Irrigation Company also installed automatic water flow measuring equipment for the canal systems to serve the regulation of water supply, contributing to saving water. Specifically, installing automatic water flow measuring equipment on Song Trau reservoir in Thuan Bac district. It’s expected that in 2022 the company will continue to set up other equipment on Northern and Southern canals of Nha Trinh irrigation system to serve water coordination between the systems.

In addition, Ninh Thuan Irrigation Company has also established tools to monitor, collect and support the reservoir management such as building database system of Lanh Ra reservoir in Ninh Phuong district by applying Google Mymaps. Digitizing the map of Nha Trinh- Lam Cam irrigation system including Northern and Southern canals, Tan Hoi and Tan Tai canals.

 “The solutions on applying technologies in the management, operation and exploitation of irrigation structures have helped NinhThuan Irrigation Company timely regulate and control the water supplies. For disaster prevention, technological equipment have play an important role in warning inbound water flow so that authorities can make plans for effectively and safely operating the reservoirs,” Luong Anh Tuan shared.

Ninh Thuan Irrigation Company has implemented Participatory Irrigation management (PIM) in seven districts and cities. This is an important solution to improve efficiency of the irrigation management in the region. Currently, Ninh Thuan province has reinforced and formed 58 cooperative organizations for 48 communes and wards with irrigation structures under the company’s management. In addition, to save water in the irrigation system, Ninh Thuan’s agricultural sector has sped up the application of drip irrigation technology.