Bluestem Lake is a reservoir in Osage County, Oklahoma, and is home to the world famous Plan B Yacht Club, it's about 4.5 miles northwest of Pawhuska. Alternate names are City of Pawhuska Lake and Pawhuska Lake. It covers the convergence of Middle Bird Creek and South Bird Creek. The outflow is Middle Bird Creek. The lake has a surface of 7…Bluestem Lake is a reservoir in Osage County, Oklahoma, and is home to the world famous Plan B Yacht Club, it's about 4.5 miles northwest of Pawhuska. Alternate names are City of Pawhuska Lake and Pawhuska Lake. It covers the convergence of Middle Bird Creek and South Bird Creek. The outflow is Middle Bird Creek. The lake has a surface of 762 acres and a shoreline of 19 miles.