Water roaring down a buried pipeline on the mountainous Fish and Cross Ranch in northwest Colorado not only powers six center pivots, but it also runs 11 big guns. And it does this with minimal labor and operating costs.
The installation of the big guns, which operate on water pressure alone, and the hydromechanical-powered pivots was driven, in part, by a considerable increase in purchased irrigation water.
In 2009, the ranch near Yampa was paying $3.50 per acre-foot of water. But when the price skyrocketed to $15, Tyler Snyder and his family knew that something needed to change to ensure the sustainability of their ranch.
“The $15 price tag for an acre-foot of water is cheap by farming standards on Colorado’s Front Range, but it’s not cheap when you ranch at 8,300 feet, and you only get one crop of grass hay each year,” Snyder says. “The water became very expensive for what we grow, and it became very clear to us that we needed to become much more efficient with our water to stretch the dollar.”
The right conversion
Converting from inefficient flood irrigation to center pivots and big guns was part of the solution, and using Mother Nature was the rest.
Water surges down 2 miles of pipeline to run both the center pivots and big guns. This irrigates 700 acres of grass meadows, of which 550 acres are hayed.
“Compared to flood irrigation, the pivots and big guns give us a much more even crop, and the water savings are huge,” Snyder says.
There is 250 feet of fall from the water source to the highest-elevation pivot. This produces 95 psi of pressure, which is enough to power the pivot. The lowest-elevation pivot is 390 feet downhill, which produces 160 psi.
“All of the water that runs through the turbines goes into the pivots,” Snyder says.
The entire system (center pivots and related hydromechanical systems, big guns and pipeline) cost $680,000.
The USDA Natural Resources Conservation Service covered $570,000 of the out-of-pocket expenses through a cost-share program directed at promoting efficient water use, cutting down on environmental impacts associated with flood irrigation and supporting renewable energy for on-farm and ranch applications.
The Fish and Cross Ranch funded the remaining $110,000, which paid for the contract labor and heavy machinery necessary for some of the work.
“That dollar figure doesn’t include the many hundreds of hours of labor provided by our family and friends,” Snyder says. “We put in the bulk of the pipeline ourselves using rented equipment, and we also had to screen the excavated dirt for the pipeline installation. Screening rocks out of the dirt was the hardest part of the whole project.”
He adds: “Without the help of NRCS and a lot of friends, we couldn’t have done this.”
NRCS provided a variety of technical expertise, including design of a filtration system to ensure that water entering the hydromechanical systems is clean.
Water from a reservoir on the mountain feeds into a creek, then into an irrigation ditch, and then into a settling pond, which removes most of the sediment.
From there, water proceeds through an infiltration gallery that removes fine sediment, and then the water infiltrates into the pipeline. The pipeline was the most expensive part of the project.
Snyder says the flood-irrigation ditch that previously went down the same hillside had eroded badly, and he and his helpers rehabilitated the area.
Asked about those who criticize the government for financially supporting such projects, Snyder responds: “Because our population keeps growing and growing, we need to continually find ways to grow more food for the masses — while conserving natural resources and protecting the environment. If we don’t continue to strive for efficiency, that’s bad for the entire world.”
Colorado takes the lead
Colorado is leading the nation in developing incentives for small hydropower projects, and some of these are being developed on ranches and farms, according to Colorado State University Extension.
Located mostly in mountainous areas, 7% of the state’s irrigated farm and ranch land (roughly 170,000 acres) has pressurization potential to produce a total of 30 megawatts of hydropower. That’s enough to serve about 20,000 homes.
Hydromechanical systems can be used to power center pivots on ranches and farms in mountainous areas of the West. In these systems, no electricity is produced; instead, water rushing downhill in a pipeline drives and pressurizes the pivots.
This same water can also be used to pressurize big guns.
Agricultural producers living in mountainous areas can also install hydroelectrical systems, which can be used to provide electricity to facilities on the ranch or farm. In addition, these systems can be connected to the electrical grid to offset on-farm and -ranch electrical consumption.
Producers installing small hydropower projects don’t have to obtain a new legal water right if the generation is combined with an existing water use.
Details about implementing on-farm and -ranch small hydropower projects, permitting, financing and the issue of water rights are covered in the CSU Extension publication “Agricultural Hydropower Generation: On-Farm.” It’s available at extension.colostate.edu/docs/pubs/natres/06708.pdf.
Waggener writes from Laramie, Wyo.