Longest Breakwater in India

The paper describes the construction details of the breakwater constructed in India for the new Ennore Coal Port Project. The primary purpose of the new port is for the importation of coal for the North Madras Thermal Power Station and other power stations. The Breakwater consists of South & North Breakwater of lengths 1040M and 3070M respectively, out of which the North breakwater is considered to be the longest in India. The rocks were supplied from a quarry (Karikkal) 125 Km away. The quarry is a virgin narrow and high hill having temples on the hill and a village near the foot. It is interspersed by layers of murrum and other soft material making winning of rock difficult. Specialized and controlled drilling and blasting was used to get various rock sizes (1 kg to 18 tons) in the required proportion to avoid wastage. Specially fabricated steel skips of 20 tons capacity were loaded on trucks/trailers for transporting rocks to a railway siding 25 Km away, and loaded in railway wagons by gantry. Each railway wagon carried 3 skips and traveled 100 Km away carrying 1800 tons of rock and unloaded at a specially designed stacking area near the breakwater to hold up to 1.5 million tons of rocks. The total quantity of rock required for the two breakwaters is about 3 million tons having seven grades of rock from 1 Kg to 18 Tons to form the quarry run, filter layer, toe layer, and the armor layers, etc.