A federal judge rejected a bid by farm industry groups to block federal and state pollution limits designed to improve the health of the Chesapeake Bay by more tightly regulating wastewater treatment, construction along waterways and agricultural runoff.

U.S. District Court Judge Sylvia Rambo in Harrisburg ruled that the U.S. Environmental Protection Agency was within its authority to work with six states and Washington, D.C., to set and enforce standards to reduce nitrogen, phosphorus and sediment that drain from rivers into the bay and harm the ecology of the nation's largest estuary.

In her 99-page decision Friday, Rambo rejected arguments that the EPA overstepped its bounds under the federal Clean Water Act, created an unfair process and used standards that were flawed or unlawfully complicated.

The EPA and the group of Chesapeake Bay states "undertook significant efforts to preserve the framework of cooperative federalism, as envisioned by the (Clean Water Act)," Rambo wrote. The act is "an 'all-compassing' and 'comprehensive' statute that envisions a strong federal role for ensuring pollution reduction."

The American Farm Bureau, which originally filed the suit in 2011, didn’t immediately say whether it would appeal.

"We are disappointed for all famers of all sizes, whether they grow food for local restaurants and markets or for national stores," spokeswoman Tracy Taylor Grondine said.

National Corn Growers Association President Pam Johnson released the following statement in response to the district court’s ruling upholding the Environmental Protection Agency’s Total Maximum Daily Load for the Chesapeake Bay:

“The National Corn Growers Association is disappointed to hear the court’s decision to uphold the TMDL in the Chesapeake Bay. We continue to believe the Chesapeake Bay TMDL goes beyond the scope of Clean Water Act authority and has a negative impact on agricultural production and innovation.

“America’s farmers are the original environmentalists. They care deeply about the land and water quality from which they make their livelihood and raise their families. However, the policies and science behind the Chesapeake Bay TMDL are wrong.

“NCGA and our agriculture partners are reviewing our options and next steps.”

The EPA called the ruling "a victory for the 17 million people in the Chesapeake Bay watershed" while other groups that supported the regulations, including the National Wildlife Federation and Chesapeake Bay Foundation, applauded Rambo's decision.

Groups that had joined the farm bureau's effort included the Fertilizer Institute, the National Pork Producers Council, the National Corn Growers Association, the National Chicken Council, the U.S. Poultry and Egg Association and the National Turkey Federation.

Farm runoff — such as animal waste and fertilizer that get into streams and rivers from watering or rainfall — is the single largest source of pollutants in the Chesapeake Bay, according to the EPA. Agriculture groups had become alarmed at the plan, saying it unfairly singled out farmers and the cost to protect waterways from runoff could devastate farmers. The National Association of Home Builders also had challenged the Chesapeake Bay plan.

To date, more than 47,000 water pollution-reduction plans have been completed throughout the United States, and the Chesapeake Bay plan is the largest and most complex so far, Rambo said.

State-federal efforts to improve the Chesapeake Bay water quality stretch back 30 years to 1983, when the governors of Maryland, Virginia and Pennsylvania, the mayor of Washington, D.C., and the head of the EPA signed the first "Chesapeake Bay Agreement."

After years of missing deadlines, the EPA and six states — Delaware, Maryland, New York, Pennsylvania, Virginia and West Virginia — and Washington, D.C., agreed in 2007 to establish a pollution-reduction program by May 1, 2011, and to reach the targeted limits by 2025.

The agreement did not violate the Clean Water Act because the EPA and the states all agreed to it and states were given the flexibility to decide how to meet the limits, Rambo wrote.