Agricultural Irrigation Water
Reverse Osmosis System for High-Value Berry Production | Sandveld, Western Cape, South Africa
PROJECT SUMMARY
Greenchain Group designed, manufactured, installed and commissioned an advanced borehole water treatment plant for a commercial strawberry farming operation in the Sandveld region of South Africa.
The system converts brackish borehole water with elevated iron and moderate salinity into irrigation-quality water suitable for sensitive berry crops. Designed to produce 300 m³ of treated water per day, the plant combines chemical oxidation, catalytic media filtration, activated carbon treatment and low-pressure reverse osmosis to deliver consistent water quality while optimising energy efficiency and water recovery.
The solution was engineered specifically to accommodate variable borehole chemistry, ensuring reliable irrigation performance as source water conditions change over time.
THE CHALLENGE
Berry production places exceptionally high demands on irrigation water quality. Elevated levels of sodium, chloride, iron and dissolved salts can reduce crop performance, affect soil health and limit long-term agricultural productivity.
The client relied on multiple boreholes with varying water chemistry, including differences in iron concentration, salinity and pH. As borehole sources are rotated throughout the year, the treatment system needed to remain effective despite fluctuations in raw water quality.
In addition to achieving strict irrigation water targets, the solution needed to maximise water recovery, minimise energy consumption and provide a practical, robust system suitable for continuous agricultural operation.
THE SOLUTION
Following comprehensive water quality analysis and process modelling, Greenchain Group developed a multi-stage treatment process tailored to the site’s specific borehole conditions.
Raw borehole water first undergoes controlled chemical oxidation and conditioning to convert dissolved iron into filterable particles while automatically adjusting pH and oxidation potential in response to changing source water conditions.
After gravity settling, catalytic DMI-65 media removes oxidised iron and manganese, and granular activated carbon protects the downstream reverse osmosis membranes by removing residual oxidants and polishing the water.
A low-pressure reverse osmosis system then reduces dissolved salts, sodium and chloride to achieve irrigation-quality water. To maximise production efficiency, the system incorporates a controlled mineral blending stage that combines a portion of the pre-treated water with reverse osmosis permeate, increasing overall water recovery while maintaining the required irrigation specifications.
Intelligent process monitoring, automated chemical dosing and online conductivity measurement enable the treatment plant to adapt to seasonal variations and changing borehole conditions while maintaining stable performance.
Key Outcomes
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Production of up to 300 m³ of irrigation-quality water per day.
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Reliable treatment of brackish borehole water for sensitive berry production.
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Reduction of sodium, chloride and dissolved salinity to crop-specific targets.
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Automated adjustment to variable borehole water quality.
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Increased water recovery through controlled mineral blending.
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Improved energy efficiency using low-pressure reverse osmosis.
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Reduced membrane fouling through advanced pre-treatment.
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Designed for long-term operational reliability and agricultural resilience.
Technical Highlights
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Borehole water treatment for irrigation.
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Treatment capacity: 300 m³/day.
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Net irrigation water production: 15 m³/hour.
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Chemical oxidation and pH conditioning.
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Gravity settling.
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DMI-65 catalytic iron and manganese removal.
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Granular activated carbon (GAC) filtration.
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Low-pressure brackish water reverse osmosis.
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Controlled mineral blending system.
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Automated pH, ORP, chlorine and conductivity monitoring.
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Variable speed pump control.
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Clean-in-place (CIP) system.
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Automated process control designed for variable borehole chemistry.
Business Impact
Reliable irrigation water is fundamental to the success of high-value crop production. Water quality directly influences crop health, yield, soil condition and long-term farm productivity.
By developing a treatment system specifically engineered around the farm’s borehole characteristics and irrigation requirements, Greenchain Group enabled the client to establish a dependable water supply capable of supporting sensitive berry cultivation despite naturally challenging groundwater conditions.
The combination of intelligent automation, energy-efficient treatment and optimised water recovery provides a solution that not only protects crop performance but also improves operational efficiency and strengthens long-term water security for agricultural production.
The project demonstrates Greenchain Group’s ability to design customised agricultural water treatment systems that balance engineering precision with practical operational outcomes for modern farming enterprises.
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Facing similar water challenges?
Whether you’re producing berries, vineyards, orchards or other high-value crops, irrigation water quality can have a significant impact on productivity, soil health and long-term profitability.
Greenchain Group designs intelligent agricultural water treatment systems that help farmers make the most of available water resources while protecting crops and supporting sustainable growth.