The four ponds inside the Guindy National Park (GNP) — Appalangulam, Kaathangollai, Duck and Bhogi — were deepened and desilted recently to improve water retention and groundwater recharge.

Forest department sources said deepening and desilting of ponds have to be done once in five years.

They added that the ponds also help in recharging the groundwater table as well as the water level in a well that is located opposite Kaathangollai. The rough estimate of daily water requirement for the Children’s Park alone is in the range of 50,000 litres, and during holidays (when there are a large number of visitors), it goes up by another 50,000 litres.

A Wildlife official said a government order was issued in December to take up works in the four ponds.

The funds were provided by the Environment department. The desilting and deepening work began simultaneously in all the four ponds in January and was completed within a month.

While it took more than 25 days to complete works at Appalangulam, it took nearly 18 days at Kaathangollai.

In the Duck and Bhogi ponds, the work went on for nearly 10 days.

At present all the four ponds are dry. Appalangulam and Duck pond were deepened by two metres, Kaathangollai by 1.5 m and Bhogi pond by 1.75 m.

A senior official said: “We are awaiting summer showers which will help in filling the ponds to their full capacity.”

Feeding channels cleaned

Even while deepening and desilting works were being done, authorities also took up the cleaning of feeder channels for these ponds.

The feeding channels are now ready to carry rainwater into the ponds, said authorities.