Walk the beach beneath Varkala Cliff and you will find fresh water coming out of the rock, a few metres from the Arabian Sea.
It is usually presented as a mystical detail — sacred springs, healing water, the reason pilgrims bathe here. That framing is real and old. It also skips the more interesting part, which is that the springs are evidence of what the cliff actually does for this coast.
How the water gets there
The cliff is a layered stack: a hard laterite cap over sandstones, sandy and plastic clays, and thin carbonaceous seams. The sandstone is porous. The clays are not.
Rain falling on the land behind soaks down through the porous beds until it reaches a clay layer it cannot pass, then travels sideways along that boundary. Where the boundary meets the open cliff face — which is exactly what a sea-cliff is, a cross-section through the whole stack — the water has nowhere left to go but out.
That is the spring. Not water welling up from a mysterious source, but the visible edge of a groundwater system that has been quietly filtering through sandstone on its way to the sea.
The part that matters to the coast
A. Bijukumar of the University of Kerala puts it about as directly as it can be put: the greatest ecosystem service offered by the cliff is water harvesting for the coast.
That is a strong claim about a landform best known for sunsets, and it follows from the structure. The cliff and the ground behind it take monsoon rain, hold it in the porous beds instead of letting it run straight off into the sea, and release it slowly through the dry months. For a coastal strip where the alternative is saline intrusion, a slow freshwater release is not a nice extra. It is the water supply.
Which reframes the conservation argument. Protecting the cliff is usually argued on heritage grounds — the type section, the layers, the science. The water case is more immediate: damage the system and the thing you lose is not only a geological reference, but the reason there is drinkable water near the shore.
Why the cap matters twice over
The laterite lid does two jobs at once, and they pull in the same direction.
Structurally, it stops rain reaching the soft beds and washing them out. Hydrologically, it regulates how water enters the system in the first place. Puncture it with foundations, drainage runs and septic seepage and you get both failures together: the soft layers saturate where they should not, and what reaches the aquifer arrives faster, dirtier and in the wrong places.
The springs are therefore a reasonable indicator of the cliff’s health. Water that is scarcer, or less clean, is the same system telling you something about what is happening on top of it.
On the beach
Go down the steps to Papanasam and look along the base of the cliff rather than out at the sea. In the wetter months the seepage is obvious — damp bands, darker rock, water tracking down the face and across the sand.
People have bathed in it for centuries and called it purifying. They were describing something real: fresh water, filtered through several million years of sandstone, arriving at a beach. The sacred reading and the geological one are describing the same event.
Frequently asked questions
Where do the Varkala springs come from?
Rain soaking into the porous sandstone beds behind and within the cliff travels down until it meets an impermeable clay layer, then moves sideways along that boundary until it reaches the open cliff face and emerges. The springs are the visible edge of that groundwater system.
Are the springs really mineral or medicinal?
The water is fresh and has filtered through the cliff’s sandstone and clay beds, which is the basis of the long-standing belief in its therapeutic quality. Treat the healing claims as tradition; the filtering is straightforward geology.
Why do people say the cliff harvests water?
Because it does. A. Bijukumar of the University of Kerala describes water harvesting for the coast as the greatest ecosystem service the cliff provides — it holds monsoon rain in its porous beds rather than shedding it to the sea, and releases it slowly, which is what keeps fresh water available near a saline shore.
How does clifftop building affect the springs?
The laterite cap regulates how water enters the system. Foundations, drainage and septic seepage puncture it, so water arrives faster, dirtier and in the wrong places — while also saturating the soft beds that hold the cliff up. The same damage harms both the structure and the water.
Can you see the springs?
Yes, at the base of the cliff along Papanasam Beach, most obviously in the wetter months — damp bands, darkened rock and water tracking across the sand. Look along the foot of the cliff rather than out to sea.