Virginia Attorney General Ken Cuccinelli, R, won a significant victory against the U.S. Environmental Protection Agency on Jan. 3. A federal district court in Virginia ruled in favor of the state in a dispute over stormwater runoff in the case Virginia Deptartment of Transportation v. EPA. As Cuccinelli said, the "EPA was literally treating water itself -- the very substance the Clean Water Act was created to protect -- as a pollutant."

In a prime example of the unlawful and economically destructive positions taken by the EPA under outgoing administrator Lisa Jackson, the agency claimed that it could regulate the stormwater running into Accotink Creek, a 25-mile-long tributary of the Potomac River. Although the EPA was forced to admit that stormwater is not a pollutant, it still claimed the authority to regulate it, claiming it was a "surrogate" for sediment, which is a regulated pollutant.

Under the Clean Water Act, the EPA evaluates the water quality standards set by states for the discharge of pollutants into their lakes and rivers. It can either accept those standards or propose its own. In Virginia's case, the EPA established its own criteria for various pollutants for Accotink Creek ("total maximum daily loads") and set a limit in 2011 on the total maximum amount of stormwater that could flow into the creek daily.

But the court rejected the EPA's attempt to exert authority over stormwater runoff. It concluded that the EPA was trying to regulate something "over which it has no statutorily granted power ... as a proxy for something over which it is granted power."

The EPA claimed it could regulate stormwater because the Clean Water Act did not specifically "forbid it" from regulating stormwater. In other words, the EPA was arguing that its authority was unlimited except where Congress had specifically limited it. As the court said, the "EPA would like to create the impression that Congress has given it loose rein to determine exactly what it could and could not regulate."

Or as Attorney General Cuccinelli put it more colorfully, "logic like that would lead the EPA to conclude that if Congress didn't prohibit it from invading Mexico, it had the authority to invade Mexico." This assertion of governmental power violates the most fundamental principles of our system of limited government.

The extremism of Jackson's EPA was also illustrated in March of last year when all nine justices of the Supreme Court ruled against the government in Sackett v. EPA. That case also involved the Clean Water Act. The EPA took the arrogant and despotic view that the Sacketts had no right to judicially contest the EPA's imposition of huge civil penalties against them for trying to build a house on their residential property.

Jackson is resigning after four years of pushing extremist ideology at the EPA, just ahead of a court-approved agreement by the EPA to finally release thousands of her personal emails that were hidden under fake names. She was apparently conducting EPA business using these "aliases to coordinate with outside anti-coal groups and engage in other activity she wouldn't want to come to light," possibly to avoid having to produce them under the Freedom of Information Act.

Since Jackson took over the agency, it has been "on a regulatory spree unprecedented in U.S. history," according to the former chairwoman of the Texas Commission on Environmental Quality, issuing more than 1,800 regulations that will cost American industry, small businesses and consumers $45 billion annually. Attorney General Cuccinelli successfully pushed back the EPA on this regulation, but Jackson's legacy is the promulgation of too many other unnecessary and unreasonable regulations that will severely damage our struggling economy.

-Hans A. von Spakovsky is a senior legal fellow at the Heritage Foundation (Twitter@HvonSpakovsky). He is the co-author of "Who's Counting? How Fraudsters and Bureaucrats Put Your Vote At Risk" (Encounter Books 2012).