Project Details
Location: British Virgin Islands
Customer: British Virgin Islands
Technology: Seawater and Brackish Water Reverse Osmosis (SWRO & BWRO)
Capacity: 2.3 million IGPD (10,456 m³/d)
Market: Municipal
Challenges
#1 Optimizing plant efficiency for sustainable water delivery
#2 Reducing water rates while maintaining quality standards
#3 Overcoming infrastructure limitations to ensure reliable water supply
Cutting the cost of providing water at Paraquita Bay
In 2014, a 2.3 million imperial gallons per day (MIGD) (10,456 m³/d) plant was commissioned to address water rate and supply issues for a population of about 23,000. Despite these efforts, high water rates continued, and the facility struggled to meet its designed capacity. In 2015, Seven Seas Water Group acquired the plant and stepped in to help operate the plant efficiently and reduce the water rate.
Design and Operational Improvements
Upon acquisition of the Paraquita Bay seawater reverse osmosis (SWRO) plant in British Virgin Islands, Seven Seas initiated a comprehensive enhancement and upgrade project. The team meticulously reviewed every instrument, valve, and mechanical component of the plant as well as all operating conditions, safety systems, electrical systems, and control systems to identify ways to improve the plant’s long-term reliability and efficiency.
Based on the findings, Seven Seas invested approximately $3 million into enhancements, and the upgrades were implemented with no disruption to the plant’s operations. The upgrades included:
- Installation of variable frequency drives on intake pumps to control feed pressure into the SWRO system, replacing inadequate manual control and pressure regulating valves
- Installation of an additional cartridge filter to improve filtration quality and membrane longevity
- Addition of a fourth calcium carbonate tank to improve flexibility in meeting product water specifications
- Installation of another second pass BWRO unit to add redundancy and ensure continuous production
- Implementation of an N+1 system at the intake to enable all five intake pumps to operate simultaneously, increasing the intake flow from 4,000 GPM to 4,500 GPM
- Replacement of high-pressure pumps with Seven Seas’ standard model, ensuring availability of spare parts since the original pumps were no longer being manufactured
- Addition of a clean-in-place mix tank to safely add chemicals and improve operational safety
- Replacement of butterfly valves on multimedia filter units to replace inadequately rated valves
- Commissioning of airburst system for intake screen cleaning to reduce the need for divers to clean
Other upgrades included camera installations for better monitoring, remote control system enhancements, flowmeter and instrumentation upgrades, and various support and structural improvements, bringing the Paraquita Bay facility up to Seven Seas’ performance and safety standards.
Flexible Financial Solutions
Seven Seas decoupled nonwater-related costs from the original water rate formula, resulting in a more favorable headline water rate for GVI. In this way, Seven Seas protected its returns while ensuring GVI benefited from a more accurate and fair rate structure. This collaborative effort involved negotiations with external financiers and not only resolved the issue but also led to substantial annual savings for GVI.
Since the initial upgrades in 2015, the Paraquita Bay facility has consistently demonstrated excellent availability and production metrics. Because of the design enhancements and redundancies introduced, Seven Seas has achieved an industry-leading availability of 98.7%, meaning that the plant is offline for maintenance only 1.3% of the time. The upgrades have ensured that the plant can meet its design capacity of 2.3 MIGD. Seven Seas remains committed to producing a constant, reliable water supply despite limited storage on the island and other distribution challenges.
Cooperative Water Treatment Partnerships
The water journey in the British Virgin Islands illustrates the complexities of large public infrastructure projects within a small island economy. GVI has made substantial investments to guarantee a reliable water supply amid a highly dynamic and challenging infrastructure system. Seven Seas has been a dependable provider, consistently ensuring efficient water production and maintaining peak performance at the Paraquita Bay plant.
Seven Seas is dedicated to helping GVI achieve its Sustainable Development Goals of providing safe and affordable drinking water to all areas and enhancing the island’s desalination capacity.
The Paraquita Bay facility plays a key role in the sustainable and efficient use of water resources by:
- Producing safe drinking water, tested daily
- Developing local expertise in water resource management
- Building and maintaining a fully local operations team
- Providing support to other Seven Seas facilities in the region.
Seven Seas provides a comprehensive water and wastewater treatment solution, known as Water-as-a-Service®. We eliminate upfront costs by taking on all operational responsibilities and charging customers based on their actual water usage.
Water Production Handled by Water Professionals
With BOO and BOOT financing, Seven Seas takes on all the duties of water and wastewater treatment with no upfront investment, charging customers only for delivered water under performance-based contracts. We offer variable-year arrangements and can buy and upgrade existing infrastructure. Our modular equipment can be efficiently scaled up or down to meet changing demand. Contact Seven Seas. Our water professionals are ready to share our many problem-solving options.
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