By Garvin Karunaratne 

I wonder what the Government Agent at Polonnaruwa was doing while the relapanawa was removed or damaged to make a walkaway. Walk ways have to be appreciated but to damage the irrigation heritage that our forefathers have bequeathed to us is unforgivable. 

The G.A’s residence is on the bund and he must have known what was happening. The G.A.  is the highest ranking officer in the District and to my thinking though the Prakrama Samudra belongs to the Irrigation Department, it should have been his concern. 

The Prakrama Samudraya is a masterpiece of irrigation engineering.  

My knowledge of irrigation work was in the Agrarian Services when minor irrigation work was taken over from the Government Agents and handed over to the Agrarian Services Department. I was in charge of minor irrigation work in the Anuradhapura District in 1963 and 64, when my team of Technical Assistants and Cultivation Superintendents did repair and rebuild tanks. 

A tank bund is no mean feat. At its base there is a core of puddled mud  mixed and  settled in like concrete. The earth is put over this puddle mud and rammed in.The  relapanawa is to withstand the waves and the water beating on the bund. I have on my inspections seen how the waters beat on the  bunds and the stone relapanawa is an essential part of a tank bund to ensure that the earth on the tank bund can withstand the beating it gets from the water of the tank. This is no mean beating when the tank is full. 

I wonder why no one in the irrigation department talked. The Relapanawa is an accepted integral part of any tank.  We should be very thankful for the MahaSangha who took up this cause. 

Our irrigation works are precious marvels bequeathed to us.  There will be no life in Polonnaruwa if not for the Parakrama Samudraya. 

I can quote a bit of the marvels in irrigation. 

The gradient of the Jaya Ganga, the fifty mile canal that brings water from the Kalaweva to Nachchaduwa and finally to the City Tanks in Anuradhapura  is on a gradient of six inches to a mile, i.e. six inches  to 5280 feet or to 63,360 inches. It is a gradient that defies all engineering knowledge today. This came to the fore when I presided over at the Cultivators Meeting of the Tanks under the Jaya Ganga in 1963, when to settle the problem of the water not reaching all tanks in time suggested a concrete base for the full length. The District Irrigation Engineer was baffled and was silent for over five minutes and then he replied that it cannot be done. How do you attend to repairs on the Jaya Ganga I quipped and he admitted that  They would never dare to touch the entirety of Jaya Ganga, but would attend to limited work  in disconnected sections.” 

Let me close with a quote from my book. 

We are all novices in the vast field of irrigation.  The Kashmiri Chronicle, the Rajatarangani  tells us that King Dighadipa wanted irrigation engineers from Sri Lanka in the ninth century., Has any one ever heard of the ancient tanks collecting silt. Our ancient engineers knew the art of designing tanks in such a manner that silt did not collect in them. It has so happened that We do not have the administrative and technical capacity to even maintain the vast irrigation systems  that have been handed over on a platter  to us by our ancient engineers.” (From How the IMF Ruined Sri Lanka and Alernative Programmes of Success,  Godages, 2006, 

It is necessary to replace the removed relapanawa immediately before the November rains. Otherwise  the Prakrama Samudra is very likely to breach. In Nuwarakalaviya it is not the rain we know in Colombo. It is a deluge that lasts for days. That will be a major disaster. Further the Relapanawa consists of massive rock boulders These boulders settle in and I would expect them to gradually sink in.at least a foot.  Thus even to restore the removed Relapanawa it is necessary that the new Relapanawa is at least a foot higher. 

Over to the Department of Irrigation. Please restore the Relapanaway in October before the onset of the monsoon rains if Polonnaruwa is to be saved. 

Garvin Karunaratne 

Former G.A. Maytara.7 th September 2021