Aral Sea Irrigation Control and Automation Program
Category: InternationalUMA Engineering Ltd., CalgaryOnce the fourth largest lake in the world, the Aral Sea in Central Asia has experienced drastic declines in its water levels since 1960. Receding sh...
UMA Engineering Ltd., Calgary
Once the fourth largest lake in the world, the Aral Sea in Central Asia has experienced drastic declines in its water levels since 1960. Receding shorelines result in severe salt dust storms, while the quality of the water in the lower reaches of the two major rivers, the Amu Darya and the Syr Darya, has become a health risk to the population.
The declining levels are the result of massive increases in the amount of water withdrawn from the rivers for irrigation. The withdrawals have reduced inflows into the landlocked sea from 50 to only 5 cubic kilometres per year. The problem is due to the fact that the amount of irrigated land in the region has increased to 7.4 million hectares, and agriculture now supports about 52 million people in the surrounding states of Kazakhstan, Kyrghyz Republic, Tajikistan, Turkmenistan and Uzbekistan. These states recently became independent after the break up of the Soviet Union.
To address the situation the World Bank in cooperation with the local governments has devised the Aral Sea Recovery Plan, which aims to mitigate the impacts of environmental degradation and implement sustainable water management strategies. The program is considered an important step in stabilizing the environment, improving economic conditions and assisting the reform process under way in the region.
The recovery plan is composed of eight programs. Program 7, “Operational Water Resources Management and Control in the Amu Darya and Syr Darya River Basins,” is intended to assist the region’s two river basin management agencies to achieve their primary objects, which are:
fair and equitable distribution of finite water to member states
development of more efficient operational plans for reservoirs and diversion points
development of a system of water management, information and communication
conveyance of water to the deltas of both major rivers and the Aral Sea.
In 1995, at the request of the World Bank, UMA Engineering conducted “Stage 1 – Scope Identification Study for Program 7.” The study concluded that the river basin management agencies required modern Supervisory Control and Data Acquisition (SCADA) systems to manage and conserve the Aral basin’s considerable water resources. With over 2,120 kilometres of rivers, 612 kilometres of main canals, and 274 control structures, the study estimated an overall SCADA system would cost U.S. $30 million.
In early 1997 a team of UMA experts arrived in Central Asia to undertake Stage 2 of Program 7, which is funded in part by the Canadian International Development Agency.
Prototype SCADA system at Dustlik Canal Headworks
To show the practical advantages of a modern SCADA system in the Aral Sea Basin, UMA and the river basin management agencies agreed to develop jointly a prototype system for the remote Dustlik Canal Headworks, which is the main canal running through the Hunger Steppe region west of Tashkent. The location is on a feeder channel of the Syr Darya River where fluctuating inflows from an upstream hydro-electric dam make flow balancing into both the diversion canal and return flow back to the Syr Darya extremely challenging. UMA and local experts designed, equipped and installed a SCADA system that incorporates an existing control system at the headworks and automatically regulates flow to both diversion and return gates.
The communication hub of the SCADA system is located at the river basin management agencies’ divisional office 40 kilometres away. Through computer and radio communications, a central dispatcher can remotely monitor and adjust flows at the headworks. A communications link allows the agencies’ headquarters in Tashkent to monitor the performance of the headworks control system and transfer timely operational instructions to the divisional office dispatcher. The SCADA system was designed to incorporate other automated structures along the Dustlik Canal in the future.
Arriving in July 1998, the UMA team installed and commissioned the new system in six weeks. At the height of the irrigation season it provides a more constant flow into the canal and maintains a more stable level upstream. In winter it maintains a constant return flow into the Syr Darya. The system also provides much needed salinity monitoring.
Implementing a complex project from half way around the world proved to be extremely challenging for the UMA team. Aside from a formidable language barrier, products and services that the western engineers often took for granted were simply not available. The team had to derive alternative solutions. For example, due to a lack of adequate maps, the team had to obtain the terrain profiles required to design the radio communications system by using the river basin management agencies’ staff equipped with altimeters. The existing electrical wiring at the Dustlik site was poor and it was difficult to obtain new supplies. As a result the team designed a highly distributed system which minimized lengthy wiring runs, simplified connections, and is easier and more economical to maintain.
UMA provided extensive technical and management training in both control systems automation and water management. Through study tours and seminars, UMA was able to expose the Central Asians to the methods used by North Americans. In time, this knowledge will be adapted by the Central Asians to resolve their own critical water management problems.
In the years to come the introduction of similar systems will help the river basin management agencies achieve their primary objects and help to stabilize the shoreline of the Aral Sea. Based on the success of the $1.4 million prototype project, UMA is now assisting the agencies to secure external funding for a more comprehensive SCADA system.
The project demonstrates how Canada’s engineering capabilities can be adapted and used to provide solutions to critical problems throughout the world.
Award winner: UMA Engineering Ltd. (prime consultant). Project team leaders: David B. Chalcroft, P.Eng., Rod C. Bower, P.Eng., Don Wiles, Jerry Dirk, Rick Scholten, P.Eng.
Client: Canadian International Development Agency
Other key players: Mount Royal College (management training), Agriteam Canada (women in development)