While solar energy is globally recognized as a clean and renewable source of electricity, solar power plants are subject to the Water (Prevention and Control of Pollution) Act, 1974 due to their operational impact on local ecosystems, massive water consumption, and the rising threat of toxic waste.

 While solar energy is globally recognized as a clean and renewable source of electricity, solar power plants are subject to the Water (Prevention and Control of Pollution) Act, 1974 due to their operational impact on local ecosystems, massive water consumption, and the rising threat of toxic waste. 

The regulatory framework enforced by the Ministry of Environment, Forest and Climate Change (MoEFCC) and the Central Pollution Control Board (CPCB) applies the Water Act to solar developments for several critical reasons: 

1. Massive Water Consumption for Panel Cleaning

To maintain generation efficiency, solar panels must be regularly washed to remove dust, bird droppings, and pollen (known as "soiling loss"). [

The Scale: Large utility-scale solar farms require thousands of liters of water per megawatt (MW) per wash cycle.
The Conflict: Because major solar parks are located in arid, water-scarce regions (such as Rajasthan and Gujarat), their heavy reliance on ground or surface water directly strains local aquifers. The Water Act ensures developers obtain mandatory Groundwater Extraction No-Objection Certificates (NOCs) and comply with strict volumetric allocations to protect local communities.

2. Groundwater and Soil Pollution from Solar Waste

As India’s early-generation solar plants age, the management of end-of-life solar modules has become a massive ecological concern. 

Solar photovoltaic (PV) cells contain heavy metals and hazardous elements like lead, cadmium, arsenic, and selenium.
Under updated environmental guidelines, improper disposal or unscientific stockpiling allows these toxic materials to leach into the soil and contaminate underground water tables. The Water Act provides the statutory authority to fine and prosecute developers who cause this form of toxic runoff. 

3. Expansion into Floating and Canal-Top Solar

To bypass land-scarcity issues, India has increasingly shifted toward floating solar projects (on reservoirs and lakes) and canal-top solar plants

Because these structures sit directly on or over open water bodies, their anchoring systems, underwater cables, and maintenance activities pose potential risks to the aquatic ecosystem and water wholesomeness. The Water Act regulates these projects to ensure that cleaning chemicals, debris, or accidental structural breakdowns do not degrade the quality of the water bodies. 

4. Regulatory Categorization and Compliance

The CPCB classifies industries into color-coded categories based on their pollution load. 

Solar power plants are designated under the "White Category," meaning they are considered practically non-polluting during day-to-day operations.
The "Consent" Rule: Thanks to recent ease-of-doing-business reforms (including the Water Amendment Act), White Category plants are generally exempted from the dual compliance of obtaining formal Consent to Establish (CTE) and Consent to Operate (CTO). 
The Catch: While they are exempted from the lengthy bureaucratic "consent" process, they are not exempt from the underlying provisions of the Water Act. They must still follow basic environmental safeguards, pay relevant state environmental fees, and allow inspections to ensure they are not actively discharging effluents or polluting water sources. 

Summary of Solar Plant Responsibilities under the Water Act:

Water Sourcing: Must obtain formal state permissions and NOCs for groundwater extraction.
Chemical Runoff: Restricted from using toxic chemical detergents during wet cleaning that could pollute the soil/water table.
Waste Management: Must strictly adhere to safe storage and disposal timelines to avoid heavy metal leaching.