The rising pollution level of the Yamuna is now a major threat to the monument of eternal love — the majestic Taj Mahal. Swarms of bugs called Goeldichironomus, which are breeding on its stagnant water, are infesting the marble walls of the monument. The result is greenish black patches on several places on the intricate floral inlay works and ledges of the 17th century marvel.
According to a report prepared by St John’s College, the polluted Yamuna has been reduced to a swamp with heavy algal growth and deposit of phosphorus (from ash), which are the primary source of food for this particular species of insect.
However, the State Pollution Control Board, Agra, was not ready to admit that the Yamuna could be any threat to the World Heritage site. Senior officials said research needed to be done to establish if there was any connection between the bugs and the polluted Yamuna.
The Archaeological Survey of India (ASI) is concerned about the bug threat which started in February itself, but its officials said that their purview is limited within the walls of the monument. The ASI cannot clean up the Yamuna, they said.
The insect attack is largely concentrated within a radius of 500 metres, including the back of the Taj (which is the worst affected), and partially on the sides facing the Mosque and that of Mehmaankhaana (royal guest house). A series of marble panels depicting plant motifs on the walls or reflective tiles used in this part of the monument are getting disfigured by such bug related depositions.
“We clean up the deposits everyday with water, but they appear again the next day,” said an ASI official, adding that the cause of the problem has to be tackled at the root.
Dr Girish Maheshwari, Head of the Department of Entomology at St John’s College in Agra, said Goeldichironomus is a bio-indicator of water quality, reflecting localised water pollution. “High concentration of phosphorus in the water and the underlined sediments of the river enhances reproductive productivity of the female and a single female may lay more than one thousand eggs at a time,” he said.
The reason for the high-levels of phosphorus in the river has been attributed to the practice of releasing the ash from bodies that are burnt at a nearby cremation ground near the river.
The adults of the species make huge swarms containing millions of individuals that get attracted to the lighted/bright surface of white stone of the Taj. The greenish black secretions on the Taj Mahal, is residue of the fecal matter of the bugs.
“But they are not expected to cause any damage to the structure beyond its discoloration,” said Dr Maheshwari.
But he expressed concern over the “highly synchronised” behaviour of the swarm of insects descending on the monument in the evenings. He also said that such insects can also create problems for visitors by entering into their eyes, nose, mouth, etc., and can thus impact tourism. According to sources in the ASI, the monument receives above 20,000 visitors per day which can go up to about 50,000-60,000, during peak periods.
For Dr Bhuvan Vikram, Superintending Archaeologist, the ASI, Agra circle, “the flow of Yamuna has to be increased to get a long term solution of the problem.” The walls of the monument are being cleaned regularly since the depositing swabs are water soluble and washed down. However, repeated scrubbing can also damage the fine marble work, he said. According to him, the arrival of monsoons will take care of the problem, in its natural course.
According to Dr Maheswari, however, the feasible solution lies in the “prevention of eutrophication of the water and the sediments of the river Yamuna near the Taj Mahal”. Eutrophication refers to slow aging process of a river/water body, resulting in its deterioration to bog or marsh. Highly eutrophic water of the river impacts on the population of small fishes, which are considered predators of the larvae of this insect. There is hardly any fish/aquatic life in the Yamuna today, his report said. This concerned stretch of the river, lies at a stone’s throw distance from the back side of Taj.
Certain temporary solutions as the deployment of the indigenous large insect trap along the shore line of the river or the use of shield security lights near the Taj Mahal can also be effective.
The sources in ASI, however, argued that basic solution lies in cleaning up the river, which falls under the responsibility of the State Pollution Control Board, Agra. However, according to Ram Karan, Regional Officer of the Pollution Board, data on the status of Bio Chemical Oxygen Demand (BoD) and Chemical Oxygen Demand (CoD) is being monitored regularly. “I have to yet hear of such an incident,” he said, to attribute the green patches on Taj walls to Yamuna pollution requires thorough scientific study.
The experts pin hope on the National Green Tribunal that has r issued notices to the Union Ministry of Environment and Forests, the Uttar Pradesh Government, UP pollution control board, State Environment impact assessment authority and others on a petition filed by environment activist DK Joshi in this regard. The next date of hearing of NGT is scheduled on May 26.