Buffalo Ridge

Buffalo Ridge is a large expanse of rolling hills in the southeastern part of the larger Coteau des Prairies, and is the second-highest point in Minnesota. It stands 1,995 feet (608 m) above sea level. Buffalo Ridge is sixty miles long and part of Lincoln County in the southwest corner of Minnesota. It is located near the small towns of Hendricks and Lake Benton.

Because of its high altitude and high average wind speed, Buffalo Ridge has been transformed into a place for creating alternative energy. Currently, over 200 wind turbines stand in the Buffalo Ridge and Lake Benton area. Buffalo Ridge is also the first wind farm created in any of the states surrounding Minnesota. [
Coteau des Prairies, a highland represented by the light areas in the this shaded relief image of southwestern Minnesota.]

Geology

Buffalo Ridge is commonly considered the elevated land extending through Lincoln, Lyon, Pipestone, Murray, Rock, and Nobles counties. It is a drainage divide separating the watersheds of the Mississippi and Missouri Rivers.

Buffalo Ridge is part of the inner coteau and is the highest point of the Coteau des Prairies in Minnesota.DNR, "Minnesota DNR", http://www.dnr.state.mn.us/ecs/251Bc/index.html.] Its bedrock is formed of Cretaceous shale, sandstone and clay that lay beneath Sioux and red Upper Precambrian quartzite. This quartzite in most areas is covered by thick deposits of glacial drift, which consists of up to 800 feet (244 m) of pre-Wisconsin age glacial till (generally considered Kansas drift) left after the glaciers receded. The inner coteau is made up of extremely stream-eroded glacial deposits of pre-Wisconsin glacial drift, which is then covered by a 6 to 15 foot (1.8 to 4.6 m) thick deposit of a wind-blown silt called loessDNR, "Minnesota DNR", http://www.dnr.state.mn.us/ecs/251Bc/index.html.] . This covering results in the creation of an area with long, gently sloping hills. Loess is an easily eroded material, and because of this there are few lakes and wetlands in the inner coteau area. Loess however promotes well established dendritic drainage networks, the majority of which flow into the Missouri River and Minnesota River systems. Loamy, well-drained soils like Mollisols-Aquolls and Udolls containing Borolls and Ustolls dominate the soils of the inner coteauDNR, "Minnesota DNR", http://www.dnr.state.mn.us/ecs/251Bc/index.html.] . On the areas of eroded glacial deposits, dry prairie and moist prairie soils like Cummins and Grigal are present. These soil types, along with the temperate climate, [USGS, "Northern Praire Research Center", http://www.npwrc.usgs.gov/resource/habitat/rlandscp/s2-2-1.htm.] combine to make perfect growing conditions for tallgrass prairie, which once covered almost the entire inner coteau.

Climate

Buffalo Ridge has a temperate climate with an average twenty-four to twenty-seven inches (0.6 to 0.7 m) of precipitation per year and thirty-six to forty inches (0.9 to 1.0 m) of snowfall per winter. The average spring thaw is around April 5 and the spring green-up generally occurs between May 1 and May 10. Peaking fall colors tend to occur around October 20 and there are generally forty to fifty thunderstorm days per year. [Paul Douglas, "Prairie Skies" (Voyager Press Inc., 1990)]

Tornado of 1992

On the weekend of June 13, 1992 a large storm struck the northwest corner of South Dakota and within a span of three hours, golf ball-sized hail and up to ten and a half inches of rain fell around the area. This was a precursor to the storm that was about to hit. On June 16, another storm struck eastern South Dakota and southwestern Minnesota destroying over one hundred homes and businesses in South Dakota. These supercells created many large damaging tornadoes. The first tornado formed in Charles Mix County and moved toward Mitchell, South Dakota. The second formed in Miner County, South Dakota and the third formed south of Pierre, South Dakota both causing considerable property damage. The fourth tornado formed near the town of Leota in southwest Minnesota and spawned a maxi tornado. It was on the ground for almost an hour and a half and completely destroyed the towns of Chandler and Lake Wilson, Minnesota. In Chandler, the property damage came to over fifteen million dollars. This tornado was later classified as an F5 tornado on the Fujita Scale and turned out to be the only F5 tornado to have occur in the United States in 1992. Another tornado formed in South Dakota later in the day and made its way to Minnesota where it struck the town of Chandler for the second time along with Colton and Dell Rapids. The storm system that created these tornadoes and severe storms finally moved east on June 18.

Geography

Several towns are located on Buffalo ridge: Lake Benton, Pipestone, Spirit Lake, Storm Lake, and Worthington; as well as near the ridge: Hendricks and Ivanhoe. Before the settlers arrived and developed the towns on and surrounding Buffalo Ridge, the Dakota Native Americans inhabited the area. It was the Dakota who created intricate pipes out of the quartzite in the Buffalo Ridge area, which today are displayed at Pipestone National Monument.

The land on Buffalo Ridge is mostly privately owned farmland. However, there is also an eighthundred acre tall grass prairie conservency which is owned and protected by The Nature Conservancy.

Hole in the Mountain Prairie

Hole in the Mountain Prairie is a nature reserve created by the Nature Conservancy. It is located on the outer edge of Buffalo Ridge and is the headwaters of Flandreau Creek. It was created to preserve the diminishing tallgrass prairie and the insects and animals native to tallgrass prairies. In the past the area had been used as a grazing area for cattle and sheep. The result being the almost extinction of the tallgrass prairie. Today the Nature Conservency manages the Hole in the Mountain with controlled burning which have led to a remarkable recovery of the native prairie vegetation [Nature Conservency, "Hole-in-the-Mountain Prairie", http://www.nature.org/wherewework/northamerica/states/minnesota/preserves/art7109.html] .

Wind farm

In 1994, a Minnesota legislative mandate increased the demand for wind power in Minnesota. Because Buffalo Ridge's geography is well suited for wind power, it has a wind power history. This history has been split into three phases of construction. The first phase took place in 1994. The first wind farm cluster was built on Buffalo Ridge in the town of Lake Benton. This first cluster was built by the Kennetech Corporation (also the owners of Buffalo Ridge) and consisted of seventy-three wind turbines. The second phase occurred in 1998. Zond Energy Systems built the next wind farm cluster in Hendricks, Minnesota. This farm consisted of one hundred and forty-three Z-750 wind turbines with each turbine standing two hundred fifty-seven feet (78 m) high and weighing around one 196,000 pounds (88,904 kg) each. Each turbine can deliver the annual electricity needs of two hundred and fifty homes. The third phase occurred in mid 1999 and added one hundred megawatts of power to the existing output.

In 2001, the Minnesota legislature required Northern States Power, now Xcel Energy, to produce or contract up to four hundred and twenty-five megawatts of wind energy by the year 2002. By that time, four hundred and fifty turbines stood on Buffalo Ridge creating three hundred megawatts of energy and delivering that power to up to 110,000 homes. By the end of 2001, Xcel Energy obtained an approval to upgrade its transmission lines on Buffalo Ridge to provide up to eight hundred and twenty-five megawatts of power. In 2006 PPM Energy and Xcel Energy began construction of a one hundred and fifty megawatt project called the MinnDakota Wind Power Project [PPM Energy,"PPM breaks ground on MinnDakota wind farm for Xcel Engergy", http://www.ppmenergy.com/rel_06.09.21.html] . This project not only adds sixty-seven more wind turbines to the Buffalo Ridge wind farm, but also adds wind turbines in Brookings County, South Dakota.

The land where the wind farm resides is privately owned farm land. To acquire a piece of this land for the use of wind turbines one must rent or lease the plot of land from the farmer who owns the land. This means that though expensive, purchasing a windmill and plot of land can be done by almost anyone. Small projects, less than two megawatts in size, are offered subsidies of 1.5 cents per kilowatt-hour for the power sold to utilities. These small projects are also exempt from property taxes, and are permitted net metering providing back up power when the wind is not generating power.

Future plans

Xcel has contracted an additional three hundred megawatts of wind energy by 2010 and must obtain ten percent of its own electricity from renewable sources by 2015. Xcel is expected to increase its wind power contracts from three hundred and two megawatts to one thousand one hundred and twenty five megawatts by 2010 [Mary Hoff, "Catch the Wind",http://www.dnr.state.mn.us/volunteer/novdec03/wind.html] .

Birds, bats, and windmills

Concerns involved with wind turbines revolve around the affected bird and bat populations that surround the Buffalo Ridge area; however this concern seems to be very minor. A study featured in "The American Midland Naturalist" found that eighty-four to eighty-five percent on the seventy species of birds that live in the Buffalo Ridge area fly above or below the height of the wind turbine blades. During a study conducted in 1996, by Western EcoSystems Technology, it was concluded that an estimated average of 1.4 birds were killed per wind turbine during the seven-month study. Another eight-month study was done in 1997 and found that 1.1 birds were killed per turbine. Also, available evidence from the “Interim Report: Bat Interactions with Wind Turbines at the Buffalo Ridge, Minnesota Wind Resource Area: 2001 Field Season,” shows that most bat mortalities caused by windmills occur during the fall to migrant and dispersing bats and not to resident breeding populations. It was concluded by this same study that 2.45 to 3.21 bats die per turbine which is lower than the number of bat deaths by lighthouses, communication towers, tall buildings, power lines, and fences [Mike Sagrillo,“Interim Report: Bat Interactions with Wind Turbines at the Buffalo Ridge, Minnesota Wind Resource Area: 2001 Field Season”,http://www.awea.org/faq/sagrillo/ms_bats_0302.html] .

In 1996, [http://www.west-inc.com/ Western EcoSystems Technolygy] was contracted by Northern States Power to create an avian monitoring program for Buffalo Ridge. Its primary goals for Buffalo Ridge were to evaluate the risks to avian species by monitoring the wind power development and its effect on the avian species while at the same time using that information to reduce avian mortalities on Buffalo Ridge. According to the studies, bird populations are in more danger from humans than from windmills.

Footnotes

ee also

*wind power
*wind farm
*Wind power in the United States
*List of large wind farms

Works cited

*"Buffalo Ridge Wind Towers." HendricksMN. 2004. Hendricks, Minnesota. 22 Apr 2007 .
*"Couteau des Prairies." Wikipedia. 2007. Wikipedia Foundation Inc.. 22 Apr 2007 .
*Dieter, Charles and Higgins, Kenneth and Osbourn, Robert and Usgaard, Richard. "Bird Flight Characteristics Near Wind Turbines in Minnesota." The American Midland Naturalist 139Jan 1998 29-38. 26 Apr 2007 .
*Douglas, Paul. Prairie Skies. Voyageur Press Inc., 1990.
*"Regional Landscape Ecosystems of Michigan, Minnesota and Wisconsin." Northern Prairie Wildlife Research Center. 03 Aug 2006. USGS. 22 Apr 2007 .
*Richter, Gary. Buffalo Ridge Tornado. 1992.
*"Wind Power on the Buffalo Ridge." The City of Lake Benton, Minnesota. govoffice.com. 22 Apr 2007 .

External links

* [http://www.west-inc.com Western EcoSystems Technology website]