Richland County, originally a part of Dawson County, was founded on May 27, 1914. The County Seat is Sidney.  Richland County is, and always has been, ranch and farm territory. The Lower Yellowstone Irrigation Project was established in 1902 and supplies irrigation to the area. Sugar beet and oat production in Richland County is number one out of all 56 counties in Montana. Richland County is home to the Elm Coulee oil Field. This field was discovered in the Williston Basin, in 2000. Horizontal drilling techniques which perforate the productive rock parallel to the beds, instead of the traditional vertical drilling, are used. In 2006 the field was producing around 100,000 barrels per day. Predictions on the total amount of oil in the Elm Coulee Field range anywhere from 270 million barrels to 500 million barrels, putting it in the top 20 largest oil fields in the United States. Today Richland County is home to approximately 10,000 people.