2022 – Modernization of the Berdavan Village Reservoir and Irrigation System in Tavush Region Funded by: The H. Hovnanian Family Foundation

Under this contract, the irrigation system built during the Soviet era—consisting of a reservoir, pump stations, and water pipelines—was planned for modernization.

Key Findings and Challenges:

Detailed field studies revealed that the irrigation system relied on two nearby pump stations. One received water by gravity from a 3,000 m³ reservoir, and the other sourced water from a deep well. However, due to climate change, underground water levels have dropped by nearly 40%, leading to reduced water levels in both the reservoir and the well.

As a result:

• The reservoir experienced sediment accumulation, reducing its volume by around 1,000 m³.
• The dam's upper slope structures deteriorated, with partial surface erosion.
• Poor system operation caused excess water to flow into Azerbaijan, without being used efficiently by the community.

Main Design and Rehabilitation Works:

1. Reservoir Reconstruction with an Earthen Dam

• Stability checks and modeling were performed based on real flow conditions.
• Anti-filtration measures, slope reinforcements, sediment removal, and dam surface restoration were included.
• A new intake structure was designed 50 meters upstream to draw water 1.5 meters higher than the existing level, enabling a design flow of 150 L/s.
• Water will be transported from the new intake to the reservoir through a 1.5m-deep earthen channel, designed per SNiP 2.06.03-85 standards.
• A geomembrane will protect the upper slope and dam crest from wave action, filtration, vegetation roots, and weathering.

2. Construction of Pump Station Sump and Supply Channel

• Demolition of the old sump and deepening of the floor by 1 meter.
• Construction of a new 45 m³ reinforced concrete sump.
• New inlet and outlet gates, and a 2.2m-wide concrete supply channel.
• Installation of reinforced control gates at the channel's entrance.

3. Renovation of Pump Station and Guardhouse Buildings

• Capital repairs included:
  • Roof reconstruction
  • Façade and window/door replacements
  • Metal gate installation
  • Construction of a canopy at the entrance
  • Installation of two 2-ton electric hoists on extended monorails
  • Concrete floor repair and interior finishes

4. Pumps and Pipe Fittings

• Two 130m head, 150 m³/h capacity pumps were installed for flexible and efficient operation.
• Old and new pump units will work autonomously, each serving specific irrigation lines.
• A check valve ensures safe operation when old and new systems run concurrently.
• Complete replacement of outdated pipelines and fittings with new, durable materials.

5. Electrical System Modernization

• The existing 560 kW oil transformer is operational, but outdated control panels were unsafe.
• Replaced with modern, reliable switchboards and protection devices.
• All power cables and conductors were fully replaced due to degradation.
• The lighting network was also fully upgraded.

6. Construction of Irrigation Pipelines

• Existing system included pressure lines from both pump stations, delivering water to high-elevation distribution chambers at 692m and 706m.
• Due to water scarcity, the first pump station was proposed to be decommissioned, and the second station used instead.
• A new underground polyethylene pipeline was built to connect the second station with the first station's original delivery line.
• New polyethylene pipelines with adequate hydrants replaced the older distribution lines.
• Topography, roadways, and utility infrastructure were considered in the layout.

Expected Results:

• ~45 hectares of land previously left unirrigated due to water shortages will now be irrigated efficiently.
• The interconnection of the two pump stations will ensure balanced water distribution and support overall system demand.
• Annual income from newly irrigated land is expected to exceed 125 million AMD starting from year 3–5.
• Reservoir volume increased from 4,000 m³ to 12,000 m³.