The decade spanning 2000 to 2009 marked a profound turning point in global environmental policy, shifting the focus from localized pollution problems to complex, systemic challenges. Traditional concerns over industrial contamination were increasingly framed within the context of global-scale threats, such as atmospheric warming and resource depletion. This period established a new framework for environmental action centered on resource security, international cooperation, and the growing scientific understanding of human influence on planetary systems. Climate change emerged as the defining environmental and political challenge of the era.
Global Climate Policy Standoffs
The early 2000s were characterized by a deep divide between international efforts to curb greenhouse gas emissions and the domestic policy of major industrialized nations. This split was underscored in March 2001 when the United States announced its decision not to implement the Kyoto Protocol, citing concerns that the treaty would harm the economy and unfairly exempt developing nations from binding commitments. Despite this international policy impasse, the scientific consensus around climate change strengthened considerably, pressuring policymakers worldwide. The Intergovernmental Panel on Climate Change (IPCC) Third Assessment Report in 2001 determined that the observed warming was “likely” due to human activities, a probability greater than 66%.
The scientific urgency increased with the IPCC’s Fourth Assessment Report in 2007, which concluded that the warming of the climate system was “unequivocal” and that it was “very likely” (over 90% probability) due to anthropogenic greenhouse gas concentrations. In the absence of a strong federal climate policy, state and regional initiatives began to fill the void. The Regional Greenhouse Gas Initiative (RGGI) was developed by Northeastern and Mid-Atlantic states, culminating in a 2005 agreement to create the nation’s first mandatory cap-and-trade program for carbon dioxide emissions from power plants.
This regional action demonstrated a commitment to market-based emissions reduction mechanisms, a concept central to future climate discussions. The RGGI cap-and-trade system officially became effective in 2009, setting a regional limit on CO2 emissions from electric power generators. These sub-national efforts laid the groundwork for broader American climate action, signaling acceptance that economic tools would be required to achieve emissions targets.
The Push for Energy Independence and Biofuels
Geopolitical instability and rising oil prices propelled energy security to the forefront of domestic policy, influencing environmental priorities. A major legislative response was the Energy Policy Act of 2005, which included the initial creation of the Renewable Fuel Standard (RFS). This mandate was designed to reduce dependence on foreign oil by requiring a minimum volume of renewable fuel to be blended into the domestic transportation fuel supply.
The push for domestic energy sources was amplified by the Energy Independence and Security Act (EISA) of 2007, which significantly expanded the RFS mandate. EISA set a target to increase the annual volume of renewable fuels to 36 billion gallons by 2022, heavily promoting corn-based ethanol and other advanced biofuels. While framed primarily as a security measure, this policy drove massive investments in the agricultural sector and biofuel production infrastructure.
The focus on biofuels introduced new environmental debates, particularly concerning land use change and the “food versus fuel” issue. Alongside the biofuel mandates, the government also provided financial incentives, such as tax credits, to encourage the development of solar, wind, and other alternative energy technologies. These incentives were justified for their environmental benefits and as strategic steps toward insulating the US economy from volatile global oil markets.
Regulatory Focus on Persistent Toxic Pollutants
The 2000s saw focused regulatory efforts targeting specific, highly toxic substances with long environmental lifespans. On the global stage, the Stockholm Convention on Persistent Organic Pollutants (POPs) was a major priority, adopted in 2001 and entering into force in May 2004. This international treaty required signatory nations to take measures to eliminate or reduce the release of POPs, which are chemicals that accumulate in the fatty tissues of humans and wildlife, such as DDT and PCBs.
Domestically, a significant regulatory battle centered on curbing mercury emissions, primarily from coal-fired power plants, which were the largest single source of airborne mercury in the US. Mercury is a neurotoxin that can cause neurological problems in children and fetuses, often entering the food chain through fish consumption. The Environmental Protection Agency (EPA) issued the Clean Air Mercury Rule (CAMR) in March 2005, proposing to reduce emissions from approximately 48 tons annually to 15 tons by 2018 through a cap-and-trade system.
This rule addressed a public health hazard through a market-based mechanism. However, the CAMR was challenged and vacated by a federal court in 2008, which ruled that the EPA had failed to follow the proper legal pathway for regulating hazardous air pollutants. Despite the court ruling, the regulatory push highlighted the decade’s commitment to addressing specific, bioaccumulative toxins separate from general air quality standards.
Prioritizing Water Scarcity and Regional Conflicts
Freshwater availability emerged in the 2000s as a significant regional and national security concern, driven by severe drought and increasing population pressure. In the American West, a multi-year megadrought, beginning around 2000, led to historic lows in major reservoirs like Lake Mead and Lake Powell. This sustained aridity intensified conflicts over the limited water allocated by the 1922 Colorado River Compact, forcing states to grapple with the reality of an over-allocated resource.
Simultaneously, the vulnerability of the Great Lakes to potential water exports became a major regional policy driver. Concerns about large-scale diversions led to the negotiation of the Great Lakes-St. Lawrence River Basin Compact. The Compact, signed by the governors of the eight Great Lakes states in 2005 and enacted as federal law in 2008, established a near-total ban on new water diversions outside the basin.
Beyond scarcity, concerns about aging infrastructure and contamination were addressed through updated public health standards. For instance, the EPA finalized a new standard for arsenic in drinking water in January 2001, lowering the maximum contaminant level from 50 parts per billion (ppb) set in 1975 to a stricter 10 ppb. This action, with compliance required by 2006, aimed to protect millions from the carcinogenic and neurological risks associated with long-term exposure.