Bhubaneswar, Nov. 21: Frequent bird-hits cases have brought Biju Patnaik International Airport under the scanner of Directorate General of Civil Aviation (DGCA) once again.

The airport is one of the 20 such facilities in the country that are under the DGCA scanner. The DGCA has called for enhanced surveillance and vigil around these 20 airports, which are either under the bird-hit threat or threat from wildlife intruding into the airport space.

Sources said a particular incident of pigs coming on the runway at Nagpur airport in September when the official Boeing-737 of President Pranab Mukherjee was taxing after landing at the airport moved the authorities to take note of the situation and issue an advisory to these airports.

City airport director Sharad Kumar told The Telegraph: "The DGCA's list comes as an advisory to be on the alert. We have been raising such issues from time to time. The drain causing waterlogging towards the Baramunda-end and the farmlands around the runway have become a cause of concern. A pond near the airport boundary wall in proximity to the closed road on the Gandamunda-end is attracting birds."

Kumar, however, said the closure of meat and fish kiosks around the airport did not yield any result, as after every eviction drive, the kiosks surfaced again.

"Thiruvananthapuram airport in Kerala has done the right thing by providing better kiosks with scientific drainage and solid waste disposal system. We can study the model and replicate it here. We cannot force people to give up their livelihood or ask citizens to go vegetarian," he said.

According to data available with the DGCA, while 378 bird-hit cases were reported in the country in 2010, the number went up to 719 last year. Pilots are advised to be careful and make every effort to avoid collision with birds, particularly when approaching or leaving aerodromes located close to towns.

In an effort to stop the airport getting affected by drain water towards the Baramunda-end, the works and water resources departments are planning to construct a special drain, as the existing one along the City Women's College-Gandamunda Road is unable to carry the water from the nearby areas.

"We would tackle the drainage issue along the City Women's College-Gandamunda Road shortly. We have already given a preliminary report to the chief secretary," said chief engineer (roads) B.C. Pradhan.