The Lake Creek Headwaters to Mainstem run on the Whitewater River in Montana is a thrilling and challenging whitewater adventure. This segment spans 6.5 miles from Section 30, T15N, R18W to Section 21, T15N, R18W. The ideal streamflow range for this segment is between 1000 to 3000 cfs, making it a Class III to IV run.

The specific rapids and obstacles on this river include boulder gardens, steep drops, and technical rapids. The most challenging rapid on this segment is the "Boxcar," which is a Class IV rapid that requires precise maneuvering. There are also several other Class III rapids, such as "S-Turn," "Bonecrusher," and "Triple Threat," which add to the excitement of this run.

It is important to note that this section of the Whitewater River is located on private property, and access is only allowed with permission from the landowners. Additionally, there are no specific regulations for this segment, but it is recommended to always wear proper safety gear, including a helmet and life jacket, and to have experience in whitewater paddling.

Overall, the Lake Creek Headwaters to Mainstem run on the Whitewater River provides a thrilling and challenging whitewater experience for experienced paddlers. It is important to check the streamflow levels and obtain permission from landowners before embarking on this adventure.