TIRUPATI: Pulicat lake, the second largest brackish water body in the country and a haunt of several migratory birds, is in peril of being extinct, if siltation continues unchecked, says NV Nanda Kumar, a retired professor of Sri Venkateswara University, who did an extensive research on the water body.
The siltation in the lake has gradually increased after the construction of a land bridge connecting Sriharikota and Sullurpet.
“The situation is further aggravated with the closure of three tidal inlets of the lake at Tuppilpalem and Rayadaruvu (Andhra Pradesh side) and Pannargattu (Tamil Nadu side).
These inlets act as biocorridors.
Further, they are important for maintaining optimum salinity in the lake, so the aqualung can thrive and the ecochronobiological process for ecosustainability of the lake continues without any hindrance,” he says.
Nanda Kumar said , the lake has become a vast evaporation basin and is fast drying up.
The migratory birds, which feed on the aquatic species in shallow waters of North Pulicat, are now bereft of the food source, thus depleting the arrival of their numbers in the region.
It has also been observed that during high winds over the lake, with no water to anchor it, fine layers of sand are swept away, particularly during summer, which gets accumulated on the road leading to SHAR from Sullurpet.
SHAR is said to be spending `2 lakh per annum for clearing the sand accumulated on the road since 1985.The sand layer is getting accumulated along the lake bed causing siltation.
If it is unchecked, the lake may become a big mudflat in near future devoid of any flora and fauna.
Experts say the sand bars closing the tidal inlets to the lake should be removed.
Dredging at the tidal inlets should be taken up regularly.
The Nellore district administration submitted a proposal to the State government in 2010 to take up dredging at the lake mouths at a cost of Rs 12.58 crore.
But the proposal is still under consideration.
Suggestions for sustainability of lake
* Here are some suggestions made by Prof NV Nanda Kumar in a research paper published in The Bioscan, a quarterly international magazine on life sciences.
* Construction of a groyne or tidal inlet wall to prevent closure of the sea mouth for at least two decades.
An ocean engineer needs to be consulted for the wall construction.
* Earthen road bridge between Sullurpet and Sriharikota Island should be converted into a concrete bridge with adequate space for free flow of water to prevent quick drying in the southern half of the shallow water area.
* Plantation of mangroves in littoral area of the island and sand bar edges instead of casuarina orchards to provide nutrition to aquatic fauna.
Mangrove leaves act as food for plankton which in turn act as food for fish and shrimp in the food chain.
* Maintenance of shallow water regimen near Rayadoruvu, Attakanithippa and Venadu with optimum salinity of brackish water during the monsoon and post-monsoon period up to April.
* Digging of water storing pits (100 x 100 ft with 1.5 ft depth) near Attakanithippa on either side of 9.5 km road bridge where a few fish species survive during the post-monsoon period (January to April), which are food for painted storks and pelicans.
* Prevention of release of effluents by aquaculture farms into Buckingham canal which ultimately reach the Pulicat lake