2 101 X The Kalawewa tank (reservoir) was fed by the Dambulu Oya river, flowing north from the central mountains.
#Kalawewa tank
3 101 X The Jayaganga canal, built in the 5th century AD, carried water some 54 miles (87 km) from the Kalawewa tank to Anuradhapura and further north. Skilful levelling and construction were needed to provide the correct gradient which allows the canal to fall 6 ins over every mile (10 cm every kilometre).
#Jayaganga canal
5 101 X Water from canals or tanks was released into natural streams or channels and from there on to the fields whenever it was required for irrigation. Strict regulations governed its release and distribution.
#Fields, Diagram of supply of water to fields
4 101 X High level sluices were operated to regulate the speed and volume of water flowing into the reservoir.
#High level sluice
9 101 X The low-level sluice pit was built of bricks lined with close-fitting smooth-faced stone, perhaps covered with clay or wood to make it watertight. Through this, the discharge of water from the reservoir was controlled by raising or lowering a door.
#Low-level sluice, Diagram showing operation of sluice pit
10 101 X The latest of Anuradhapura's reservoirs to be built, probably in the 1st century BC, Nuwarawewa covers 3180 acres.
#Nuwarawewa
6 101 X The 396 acre Tissawewa tank may perhaps be identified with a reservoir built in the 4th century BC by enlarging a pre-existing natural pond. It was probably further enlarged by Devanampiya Tissa, from whom it takes its name.
#Tissawewa, Pretty picture library illustration of this tank
11 102 E Fine stone-built bathing tanks at Anuradhapura were supplied with water through underground pipelines from the reservoirs by the 1st century AD.
#Bathing tanks, Lovely bathing tank at Anuradhapura
