13°14′10″N80°19′00″E / 13.23611°N 80.31667°E /13.23611; 80.31667
Ennore Creek is abackwater located inEnnore,Chennai along theCoromandel Coast of theBay of Bengal. It is located in the zone comprising lagoons withsalt marshes and backwaters, submerged under water during high tide and forming an arm of the sea with the opening to the Bay of Bengal at the creek. The zone is spread over 4 km2,[1] and the creek covers an area of 2.25 km2.[2]
It is located 20 km north of the city centre and 2.6 km south of theEnnore Port; the creek area stretches 3 km into the sea and 5 km along the coast. The creek is nearly 400 m wide, elongated in northeast–southwest direction and merges with the backwater bodies. Once a flourishingmangrove swamp, the creek has been degraded to patches in the fringes mainly due to human activities in the region. The depth of the creek varies between 1 and 2 m and is shallow near the mouth. The north–south trending channels of the creek connect it with thePulicat Lake to the north and with the distributaries of theKosasthalaiyar River in the south. The northwestern part of the creek merges with the tidal flats. The soil in the region isloamy and alluvial. Most of the area consists of tracts ofalluvial soil and the eastern region comprises beach dunes, tidal flats and creek. The creek is oriented from west to east and opens into the Bay of Bengal to the east at Ennore. The creek acts as an outlet for the excess water from thePoondi reservoir. The creek separates the town of Ennore from the Ennore Port located in the north and theKattupalli Shipyard located further north.
TheNorth Chennai Thermal Power Station is located to the north of the creek and the Ennore Thermal Power Station is located to the south. The creek is part of the Pulicat water system, including the Pulicat lagoon and theBuckingham Canal. As per the1991 Coastal Regulation Zone notification, the entire Pulicat water system is designated CRZ I.[3] The creek is experiencingsiltation due to emergence of the Ennore Port.
According to the Department of Environment, the zone covers an area of 6,469 acres of the creek identified as a tidal waterbody protected as a No-Development zone under CRZ-I regulations.[4]
The region is drained by a couple of seasonal rivers, namely,Araniar River flowing in the north andKosasthalaiyar River passing through the creek, fed chiefly by the northeast monsoon and the cyclonic storms of the eastern coast between October and December and, to a lesser extent, by the southwest monsoon. The annual rainfall is about 1200 mm per annum and the temperature ranges from 25 °C to 40 °C. The water flow is scanty during most part of the year with occasional floods in the event ofcyclonic storms. These rivers, which are source forgroundwater recharge in the region, support several lakes found in the area.[5]
Both the rivers do not reach the sea directly but confluence in thebrackish water bodies, mangroves situated at the fringes of the creek and theBuckingham Canal. The Kosasthalaiyar River drains into the Ennore backwaters reaching the sea through the creek. The littoral currents moving in a northerly direction for 9 months from February till October transport the sediments and deposit them few kilometres off shore and, in an area of emergence, these strands form strand plains.[5]
The mean wind speed in the region is about 4.7 m/s. The flux-level changes vary from 0.4 to 6 m3/s/m2. Surface elevation ranges from 0.2 to 0.6 m. The current velocity at the creek varies from 0.08 to 0.16 m/s during flood tides and from 0.2 to 0.15 m/s during ebb tides. At the mouth, the current velocity towards the east reaches a maximum of 0.5 m/s during flooding and 0.3 m/s during ebbing conditions.
The mangrove region found in theestuarine area supports a number of wildlife. The creek is surrounded by fishing villages, croplands and aquaculture ponds. Salt manufacturing, lime shell quarrying and fishing remains the chief occupations of the region.[6] The northern part of the creek is connected to the biodiversity-rich Pulicat lagoon through the Buckingham Canal.
The creek receives wastewater from numerous sources including untreated wastewater and treated effluents from industrial sources in the surrounding area. Studies reveal that permitted discharges account for less than 40% of the total BOD load measured in the creek.[1] Heavy metal concentrations are found to be higher near the creek mouth compared with the nearshore waters. Majority of heavy metal pollutants are likely to be present in a close proximity range of 0.5 km from the creek mouth after which there is a steady decline in their concentration up to 1.5 km.[7]
In January 2017, a collision of two ships,Dawn Kanchipuram andBW Maple, at theEnnore Port resulted in an estimated 251.46 tonnes of oil spill.[8]
In 2000, an artificialbeach nourishment (to prevent downdrifterosion) was taken up by placing 3.5 million m3 of sand dredged from the Ennore harbour basin and the approach channel through capital dredging.[9]
A 670-m-long two-lane bridge is constructed on the creek by the Highway Department at a cost of₹ 560 million, connecting Ennore High Road off the coastline withNorth Chennai Thermal Power Station at the northern end of the creek, with approach roads for about 1.7 km on either side of the Ennore High Road and near the thermal power station.[10][11] The project, however, was proposed way back in 1997.[12]
