The Lifeline of Coimbatore

Long ago the sacred serpent adorning the neck of Lord Shiva was unable to bear the fury of his cosmic dance and therefore spat the venom of destruction all over the Universe. The Devas led by Brahma approached Lord Shiva for help and he commandeered River Ganga to flow from heaven and cleanse the Universe. The River formed thus emerged from the Vellingiri region of the Western Ghats and therefore came to be known as Adhi Gangai, Shiva nadhi and later Noyyal - because of the soft sand on its banks and also as it means ‘small’ in ancient Tamil, very appropriate for a river that flows only for about 160 kms in the Coimbatore, Tirupur, Erode and Karur districts of Tamil Nadu before merging herself into the mighty Kaveri at Noyyal Village near Karur.

This cosmic dance of Shiva and the stillness of his posture adopted by Him to make His divine serpent comfortable is epitomized by the icon of Nataraja at Perur, where His matted hair-locks are frozen. Thanks to the cosmic dance and Divine concern we have Mother Noyyal nourishing Coimbatore from time immemorial.

Noyyal in History, Literature and Commerce

Our River Noyyal supported dense forests in the Western Ghats region and its many streamlets including Chinnar, Periyar and Kanchimaanadhi that merge at Kooduthurai near Madhavarayapuram thereby joining together to bring forth their combined flow as one single strong river. According to Tamil Literature there existed a civilization on the banks of River Noyyal during 300 BC and unto the Sangam Era.

  The progenitors of this ‘River Noyyal Civilization’ settled down on the banks of this river and involved themselves in agriculture, textiles, smithy, and jewelry manufacture. Later they exported the same to Room along with the spices of our country. Besides the prosperity ushered in by the bounties provided by River Noyyal, Roman gold gave additional wealth to this region. Roman merchants established settlements at Vellalore on the banks of Noyyal and this was a part of the Roman Spice Route for hundreds of years. Along with the waters of prosperity River Noyyal has continued to carry mythological tales, fables like the story of Karikala and the ghost, over the ages. In fact it was Karikala Chola who built the Cholanthurai on the banks of the river near the Perur Patteeswarar Temple. 

For hundreds of years River Noyyal flowed untamed into the Cauvery and the rulers of the land travelled westward to study the origins of this river .In order to harness the same, they decked River Noyyal with anicuts, lakes and connecting channels thereby increasing the agricultural produce of this region. Thanks to the hydrological adornments River Noyyal continued to serve the citizens as a calm river and this has been well brought out in the ‘Perur Puranam’ of the 17th century by Kachiappa Munivar, where he goes on to say that being chaste, the river never breaches her embankments.

Development of the Noyyal Infrastructure

Originally Karikala Chola the Great was the first to harness a riverine system in Peninsular India. He constructed the Kallanai near Srirangam and this subsequently enabled the breaking up of Cauvery into a network of canals, rivulets, tanks and ponds.

Thanks to these developments the Chola country became rich, powerful and cultured. The Eleventh century witnessed the construction of the Brihadeeswarar temple and the same acted as a ‘bandaram’ or bank during the reign of Raj Raja Chola I. The temple was enabled to hold about 1,15,000 sacks plus of paddy on its books at any given point of time.

The ‘Eri’ system of Tamil Nadu was quite evolved by this time. Typically, a check dam was constructed across a river and a part of it was diverted to a tank. Once the tank got filled up, water was released through an outlet and it went on to fill up one more neighborhood tank. Thereafter the water was brought back to the river from the tank after filling up the same. Most of the canals also did have outlets which supported wayside agricultural lands.

The concept of slowing down the flow of water was essential for the rivers would quickly drain themselves into the seas and oceans. The Noyyal has been a monsoon fed river and therefore it has been essential to store water for agricultural and other purposes as well. Our ancestors made the running water to walk, the working water to squat and percolate within the underground aquifers that were reached through the various layers of soil.

Perhaps this has been allegorically represented on the matted locks of Shiva which demonstrate the flow of Ganges being regulated on a continuous basis.

Evidence of irrigation using such water harvesting methods have been in India over 4000 years and details pertaining to such systems are even found in Kautilya’s Arthashastra which belongs to the third century BC. This Magnum Opus of Chanakya indicates that people knew about rainfall regimes, soil types and irrigation techniques. It also mentions that the state rendered help for the construction of irrigation works, initiated and managed by the inhabitants of a newly settled village. Archaeological and historical records show that Indians were constructing dams, lakes and irrigation systems in the time of Chandragupta Maurya (327-297BC). Checkdams built with stone rubble during the 3rd Millennium BC have been found in Baluchistan and Kutch.

The Rajatarangini of Kalhana, a twelfth century account of Kashmir describes a well-maintained irrigation system. King Bhoja constructed 65,000 hectare tank and the same was fed by 365 streams and springs. The Bengal’s overflow system of irrigation worked well until the advent of the British. Thus Indians developed a range of techniques to harvest every possible form of water from the rainwater to groundwater, stream to river water and flood water.

One-third of the irrigated area of Tamil Nadu is watered by ancient tanks called ‘eris’, which have played several important roles in maintaining ecological harmony - flood control, preventing soil erosion, reducing wastage of run off and also recharging the groundwater of the state. 

The Western Ghats:

The Western Ghats are amongst the most exotic eco-spots of the world. They are also known as the Shayadris and they have given us all major Peninsular rivers – Godavari, Krishna, Tungabhadra, Cauvery, Bhavani, Amaravathi and Noyyal. The mountain ranges are home to extraordinary biodiversity. There are several forests, waterfalls and grasslands associated with these mountains. Without the Western Ghats, Peninsular India would be a one great desert. 

The forest of the Western Ghats associated with the Noyyal basin and its environs are home to over one hundred and fifty species of birds belonging to our region and also ones which migrate during winter.

The Nilgiri Biosphere associated with our region is the largest home for the asiatic elephants. Our river Noyyal arises out of the Western Ghats and travels through the horse-shoe shaped Valley in the form of over 30 rivulets which can be seen as silver silvers on the hills during the monsoons.

Riparian Forests and Bird Life

The various streams making up River Noyyal had riparian forests adjacent to them. The trees on either sides of the streams forming River Noyyal added medicinal properties and stability to the river. These forests also did act as a water-shed for the region. Thanks to the abundance of water and greenery birds used to stay in this region on a regular basis. The birds in turn ensured that the seeds strewn by them propagated the greenery further. Elephants, Indian gaur, Deer, Nilgiri Tahr, Wild dogs amongst others were found here in abundance. The Noyyal River forest was kind of an ecological paradise which yielded a salubrious weather to Coimbatore.

The Noyyal River Basin of the yonder era

Coimbatore and its environs were made up of tanks connected through canals, paddy fields, Perur temple, the horseshoe Noyyal valley with its 30 plus rivulets, abundant bird life, herbivorous and carnivorous animals, varieties of trees, plants and creepers, network of tribal and agrarian villagers, Roman settlements along the trade route, weavers, woodworkers, making agricultural implements, craftsmen working on Cornelian gems, milch cows, poets and priests praising Mother Nature and the Lord almighty for endowing the populace with bountiful wealth. Once harnessed, the Noyyal region of Coimbatore attracted the attention of all major dynasties, thereby it acquired a cosmopolitan flavor. The wealth and taste of the River Noyyal ensured peace and progress for centuries.

Climate and rainfall

Generally sub-tropical weather conditions prevail in the Coimbatore region. However there is no sharp variation in the climate. One can notice the temperature slowly rising up to the maximum in summer up to May and declining slowly thereafter. The maximum temperature ranges from 36 degrees Celsius to 41 degree Celsius while the minimum temperature varies from 14 degree Celsius - 31 degrees Celsius.

The annual rainfall of the Noyyal basin is 605 millimeters from 4 distinct seasons namely winter, summer, south-west monsoon and north-east monsoon. While there is rain during both the monsoons, the North-East contributes the most during October and November.

The Noyyal River Basin

The Noyyal River basin is 180 kilometers long and 25 kilometers wide thereby covering a total area of over 3500 square kilometers. The cultivated land in this basin amounts to about 1800 square kilometers. The area is known for its scanty rainfall and the development of the tank and check dam system to hold any overflow from the rains plus the water of the North-East and South-West monsoons was ecologically important. Thus, the river filled about 32 tanks with the assistance of various canals and check dams.