By Mr Carlos J Lazo (USACE)April 12, 2012
It began with four thousand legs. In the last month, it's grown an additional two hundred. It decimates every area it's brought into but, then again, that's exactly the point.
The "it" is a herd of more than 1,000 sheep and goats working their way around parts of Success Lake near Porterville, Calif. The lake is one of ten lakes and recreational sites managed by the U.S. Army Corps of Engineers Sacramento District.
One part of the Corps' dam safety program is to keep dams free of vegetation. Additionally, every year, vegetation at the lake needs to be cut in order to minimize the potential for fire once it dries. In years past, that vegetation has been removed by workers with mowers or weed trimmers or through the use of control burns. Machines break, workers get tired, and controlled burns require precise conditions and all of these measures can be expensive. A herd of sheep and goats on the other hand, require much less hassle and are much safer for the environment.
"In the past, whether it be herbicide application, tilling using gas or diesel powered machinery, and or controlled burns -- all of those things are not necessarily that environmentally friendly," said Calvin Foster, an operations area manager with the Sacramento District.
"Some of the benefits of this is its environmentally friendly," said Foster.
An added benefit is the cost.
"We were looking to pay [the herd owner] to bring his livestock out onto the dam at Success Lake and Frasier Dike," said Foster. "As it turns out, we also had an area that we were closing to the public that also had vegetation to be removed to reduce fire hazards. Once we provided the additional acreage, he basically agreed to do it for free."
Once the agreement was in place, the herd was brought in and Foster saw the benefits immediately.
"They started in Rocky Hill Recreation Area; it took them about a week to make their way along the shoreline there," he said.
Rocky Hill was closed for maintenance March 9, which includes repaving sections of the road leading to area and replacement of water lines. Taking advantage of the closure, the herd was brought in to naturally mow the shoreline adjacent to the recreation area.
"Then we moved them to Frazier Dike, where they are currently grazing," said Foster. "In route, we had an area that needed to be grazed to make a fire break. We were able to utilize the sheep, as they made their way to Frazier Dike to make this fire break for us."
When it comes to eating, the herd does not discriminate. In order to ensure only selected areas are grazed, certain controls were brought in.
"There is an individual that stays with the herd, 24 hours a day," said Foster, "and he has three dogs that are trained to help him keep the sheep inside the boundaries and to move them along."
There is also a fence system, called a "hot wire," with an electric charge from a 12-volt battery that helps keep the herd in and any predators out. As of April 12, the herd is nearly complete with one side of the dike and stands ready to cross over to the other side. Working through rain or shine, not much slows down the herd's progress. The only constant interruption is also one Foster doesn't mind much.
"This is spring, so it's birthing season," said Foster. "That impacts the speed with which the herd can move."
At least 50 little ones have been born during the four weeks the herd has been at the lake. The increase only means one thing for Foster.
"More mouths to feed and plenty of grass for them to eat," he said.
Once the herd is done at Frazier Dike, the herd owner will take about 200 of his goats and put them on the dam, to remove vegetation there.
"We took this on as a test project; it's proven to be successful," said Foster.
"The real test will be when we put the goats on to the dam itself with the steep slope and all of the rock," said Foster. "I know that they can, they've done that type of thing before, so hopefully it will be successful as Frazier Dike."
If the herd's success continues at Success Lake, it could find itself with more work next year, possibly at other recreational sites as well.