About 100 farmers in Klamath Falls, Ore., used an irrigation pipe to route a flow of water around a closed canal head gate Sunday, replenishing a canal that has been parched since water was shut off last April to protect threatened and endangered fish.

The farmers, who have been camping out at the canal head gate for the past few days, placed a pump in Upper Klamath Lake and ran the 200-yard-long pipe along a fence and into the canal on the other side of the gate, federal and county officials said. The farmers' Web site said the pipe was eight inches in diameter.

Federal agents with the U.S. Bureau of Reclamation were monitoring the situation, but did not plan to arrest anyone, said Jeff McCracken, a Bureau spokesman.

"It remains peaceful and it remains the goal ... to do everything that we can to see that it stays peaceful," he said.

McCracken estimated that farmers, who began operating the line around 2 p.m., were draining between five and 10 cubic feet of water per second from the lake.

"This is symbolic," he said. "There's no way that amount of water could be used for the crops at this time of the year."

Pat Foulk, a spokeswoman for the U.S. Fish and Wildlife Service, said officers were at the scene to make sure the farmers did not violate the federal Endangered Species Act.

She said there were no immediate plans to arrest any protesters because no fish were being sucked through the head gate and the lake's water level had not dropped.

"This is not a situation the agency had contemplated," she said. "Certainly we have concern about the safety of the crowd and the officers on the scene. We do not put the Endangered Species Act above human health and safety."

Last April, the U.S. Bureau of Reclamation was forced to cut off water to 90 percent of the land in the Klamath Project in favor of endangered sucker fish in Upper Klamath Lake and threatened coho salmon in the Klamath River.

Since the water was shut off, farms with no other source of water have been forced to sell off cattle, let pastures and hay fields go brown and give up annual plantings of potatoes, grain and other crops.

Angry groups have wrenched opened the head gates four times, most recently on Friday. Federal marshals took protesters by surprise early Saturday morning and shut the gates.

The Bureau of Reclamation closed the head gate each time, citing the Endangered Species Act, which prohibits federal agencies from doing anything to jeopardize the survival of protected species.

The federal action marks the first time that salmon fishermen and the Klamath Tribes, who once depended on the fish for food, have won out over farmers on water allocations since the irrigation system known as the Klamath Project opened in 1907.

On Sunday, dozens of farmers continued to camp out along the irrigation canal. They had set up two awnings and installed portable toilets, lawn chairs and picnic supplies outside a chain link fence separating them from the canal.

Farmers cheered, sang songs and played guitar to pass the time.

"It's proving a point that we care about our rights as Americans," said Doug Staff, a local farmer who said he would risk arrest to keep the water flowing.

The Associated Press contributed to this report