Sources of pollution are generally categorized into point and nonpoint pollution. Nonpoint source (NPS) pollution refers to diffused pollution of our environment that does not originate from an identifiable point pollution source. NPS generally results from atmospheric deposition, precipitation and land run off and seepage to the soil and groundwater. Tracing the source of nonpoint pollution is often difficult.
Types of NPS of water pollution include sediment, nutrients, toxic contaminants and pathogens. The processes responsible include: runoff in urban and suburban areas and highways, agricultural operations, atmospheric inputs, forestry and mining operations, and boating and shipping activities. In urban areas, contaminated storm water washed off of parking lots, roads and highways, called urban runoff, is usually included under the category of non-point sources (it can become a point source if it is channelled into stormwater systems and discharged through pipes to local surface waters). In agriculture, the leaching out of nitrogen compounds from fertilized agricultural lands is a NPS water pollution. Nutrient runoff in storm water from “sheet flow” over an agricultural field or a forest are also examples of NPS pollution. Another major source of NPS of water pollution includes leachates from land disposal and saltwater intrusion.
Agricultural non-point source pollution has long been considered an important factor affecting the level of eutrophication. For example, agricultural NPS pollution is estimated to be responsible for 52 and 54% of the total loading of nitrogen (TN) and phosphorus (TP), respectively in Taihu Lake Basin, China. Appropriate management of agricultural runoff and animal waste is a large concern for the U.S. Environmental Protection Agency (USEPA) and U.S. Department of Agriculture (USDA).
In India in 1995, it was found that agricultural applications of HCH, DDT, aldrin, endosulfan, and organophosphates contributed as much as 0.708, 0.682, 0.200, 0.374, and 0.926 g/ha, respectively, to the river water. In all, 2.890 g/ha was transported to the river. These values were in close agreement with overall contribution of agricultural fields to the river Ganga calculated on the basis of the amount of insecticides actually flowing in water at Farrukhabad and total catchment area from Haridwar to Farrukhabad.
A study conducted in 2010 indicated that nitrogen loss through leaching in kharif and rabi rice is of the order of 34.9% and 39.8% of the applied nitrogenous fertilizer in the Indo-Gangetic plain region. Clearly, we need an instrument to reduce the NPS pollutant load from agricultural fields with the help of rural landscape management.
My Professor Friend says that there is no point to discuss the challenge of non-point pollution with our Central and State Pollution Control Boards (PCB). According to him, pollution to a PCB is only understood as arising from the point sources that can be easily identified (e.g. drains and stacks), measured and controlled. But that is like addressing only half of the problem. “Polluters” responsible for agriculture return waters, urban runoffs are not required to apply for a consent!” I agreed with this point of view. India’s Water (Prevention and Control of Pollution) Act of 1974 is silent on management of nonpoint sources of water pollution. Maybe we need to set up “Non-Point Pollution Control Boards” and a mechanism that focusses on policy, planning and infrastructure related measures and financing to prevent and control NPS.
We decided to go to our usual coffee shop for Sunday morning breakfast for brainstorming. I had just returned from a 5 week holiday from the United States and had attended a National Groundwater Contamination roundtable organized by Professor Clement Prabhakar at the University of Alabama. I cited an example of the National Pollutant Discharge Elimination System (NPDES) in the US that looked at both Point and Nonpoint sources of pollution.
In the United States, as per the Clean Water Act (CWA) permits are required to obtain a consent or authorization for nonpoint pollution e.g. by the watershed management authorities and municipalities and the States, citing the measures that will be undertaken. The measures should have a policy-plan-program-projects (4P) mix of actions.
Under section 319 of the CWA. The US EPA sets the appropriate guidance for NPDES nonpoint areas to States that have sought authorization. Authorization for states, tribes, and territories is through a process that is defined by Clean Water Act (CWA) Section 402 (b) and 40 CFR Part 123. See here Memorandum of Agreements Between EPA and States Authorized to Implement the National Pollutant Discharge Elimination System (NPDES) Program. Monitoring of nonpoint pollution is explicitly addressed in the program that is missing in India’s national water quality monitoring program
I shuddered however if the complex system of NPDES permits and authorization is brought in India. While establishing such a framework will be a herculean task, the already stressed and understaffed PCBs will certainly collapse and won’t be able to enforce on the NPS. So then, what’s the Point?
After listening to me and closing our conversation, Professor lighted his cigar and remarked “Dr Modak, NPDES like system on NPS sounds good but apart from developing the system, financing is the key. We need to mobilize the funds at State and national levels. But prioritizing funds set for NPS is equally important”. He elaborated a case of Clean Water State Revolving Fund (CWSRF) in the United States.
The CWRF is, by far, United States largest fund dedicated to the purpose of addressing water quality problems. Congress established the fund in 1987 as a means to address both point source and NPS. Unfortunately, 90% of the $145 billion provided are currently spent on control of point pollution sources, although NPS pollution accounts for approximately three out of four identified hot spots. In 2021, US EPA published a guide on how to use the CWRF for NPS management. The guide provides case studies of successful and innovative partnerships underway across the country to stimulate spending funds for NPS prevention and control.
So apart from mobilizing funds, identification, assessment and prioritization of NPS hot spots is equally important. Could the sum of funds lying at the Central Pollution Control Board as a result of the fines levied by the National Green Tribunal (NGT) be used? Most of these funds are hardly utilized. But a friend from NGT told me that such a reallocation of funds will not be possible. So we may need a special fund like CWRF to address NPS.
In any case, there is “no point” to limit the enforcement to point sources of pollution. Pollution is often invisible. We better grow up.
image sourced from https://myconcealeddepression.com/today-im-feeling-like-whats-the-point/
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As always, very well writren. Particularly agree fully with the paragraph beginning with ‘I shuddered…’. Texts of many consents with point sources are often so poor and confusing, one may wondee what the level of confusion may be with NPS coming in. Also, i am not sure how many companies with bif ESG agendas hqve given effective consideration to this.
True. The negligence by Pollution Control Boards to Non Point Sources of Pollution from Agricultural Runoff has been used by many agro-based industries in India to dispose of their wastes under the fertile-irrigation method. Even municipal domestic wastes also contribute to NPS. In Brazil direct ferti-irrigation is accepted practice. It is a controversial topic .