Ancient Goa was reclaimed from the marshy deltas by remnants of the Saraswat Civilization who settled there and brought with them their ancient technology. We need to learn from these ancient structures that have survived nearly 8000 years and therefore are truly sustainable. Their construction method needs to be replicated to help India’s growing infrastructure demand and lowland reclamation. They use renewable, locally available materials like Soil, Lime, Ash, Cowdung and Straw. They are multi functional: habitation, irrigation, pisiculture, agriculture, rainwater harvesting, infrastructure etc. they possess a stable shape. They save at an average 80% more space than standard embankments. A 6-8% mix of Lime and Coconut Leaf Ash gave best results for soil stabilization. They have good slope stability with a factor of safety of more than 1.5. They have no seepage problems. The self-repairing sustainable coconut tree root system provided 20% more shear strength and seismic stability. As they have already existed for many years they are already undergone settlement and consolidation. This is green engineering that has scope for ancient technology aiding modern technology and spurring India’s growth in it race for international primacy as a technological superpower.