Explained: How Does The GRAP Help Combat Air Pollution In Delhi NCR?

The Commission for Air Quality Management (CAQM) on Thursday ordered the implementation of Stage 1 of the Graded Response Action Plan (GRAP) after Delhi's 24-hour average Air Quality Index (AQI) stood at 211 (poor category) at 4 pm on Dussehra. The Centre's sub-committee on GRAP noted in a meeting that there has been a “sudden dip” in air quality parameters in the region which has pushed Delhi's AQI into the 'poor' category.

While the Delhiites are approaching another ‘breath-taking’ winter in a literal sense, it is high time to look at the response plans of the Government that may give some respite to them.

What is the Graded Response Action Plan?

The GRAP is a set of emergency measures effected to prevent the deterioration of air quality after it reaches a certain threshold.

It envisions a four-stage ad-hoc mechanism wherein Stage 1 of GRAP is activated when the AQI is in the ‘poor’ category (201 to 300), while the second, third and fourth stages are activated three days ahead of the AQI reaching the ‘very poor’ category (301 to 400), ‘severe’ category (401 to 450) and ‘severe +’ category (above 450) respectively.

When was the GRAP first introduced?

The origin of the GRAP dates back to the 2016 Supreme Court verdict in the M.C Mehta v/s Union of India case, which directed state authorities to take incremental steps to maintain ambient air quality standards in the Delhi NCR. The plan initially included measures for three stages: ‘Moderate & Poor, Very Poor, and Severe.’ A fourth stage of ‘Severe+ or Emergency’ was added later. Air quality monitoring and meteorological forecasts are based on data from the Indian Institute of Tropical Meteorology (IITM) and the India Meteorological Department (IMD).

How has the GRAP evolved over the years?

The GRAP was first notified by the Ministry of Environment in 2017 and initially monitored only PM 2.5 and PM 10 levels. However, following a modification in 2020, the plan now focuses on a more comprehensive AQI, which accounts for other pollutants such as ozone, sulphur dioxide, and oxides of nitrogen as well.

Furthermore, till 2020, the Supreme Court-appointed Environment Pollution (Prevention & Control) Authority (EPCA) implemented the plan, but this was dissolved two years ago and the responsibility to enforce the GRAP now rests with the CAQM.

A sub-committee of the GRAP is the key decision-making body and includes senior members of the CAQM, member secretaries of pollution control boards of four states of Uttar Pradesh, Delhi, Haryana, Rajasthan, as well as from the Central Pollution Control Board. The committee also has scientific and health advisers.

What measures are imposed under the different Stages of the GRAP?

The pre-emptive measures under the GRAP work on an incremental basis. When Stage 2 measures are implemented, the Stage 1 measures will automatically continue to remain in force. Stage 1 orders of October 6 include enforcement of pollution control and penal provisions for polluting industries, halting construction and demolition activities, mechanised sweeping and water sprinkling on roads, use of anti-smog guns and smog towers, enforcing ban on open burning of waste and PUC (pollution under control norms) for vehicles.

Stage 4 measures are the most extreme and may include shutting down schools and offices, plying of vehicles on an odd-even basis, and restricting entry of truck traffic in Delhi.

What factors contribute to seasonal air pollution in Delhi NCR?

The region witnesses high levels of air pollution in the winter months every year owing to a host of factors and the latest notification is not a one-off issue. Being a landlocked area, the region’s geography regularly exacerbates the problem of pollution.

Lowered temperatures in the winters create a high-pressure area, which attracts westernly winds from Rajasthan, and sometimes Pakistan and Afghanistan that bring in the dust to the region. The Himalayas further obstruct the escape route of the air which causes the dust and pollutants to settle in the region.

Other factors such as rising population and vehicular traffic, unplanned urban development, unscientific waste disposal, fossil fuel combustion, stubble burning in the neighbouring agricultural states, and use of firecrackers are also significant contributors to pollution.  

What caused the AQI to dip on Wednesday?

The CAQM has attributed the recent deterioration in air quality to “localised influence” with the possible sources of higher emissions considered to be the large number of effigies burnt on the occasion of Dussehra and during a political protest.

This was reiterated by the IITM officials who said that they did not record any substantial changes in parameters like temperature, wind speed and emissions from farm fires on October 5 and instead believed that “hyperlocal emissions” have impacted the air quality.

(With PTI Inputs)