William O'Brien State Park
William O'Brien State Park is a state park in Washington County. It was established in 1947. 8 graded lakes are within 15 miles of the park, including Unnamed Lake, Square Lake, Big Carnelian Lake.
Designation
State Park
County
Washington County
Established
1947
Official Resources
Nearby Graded Lakes (within 15 mi)
Lakes closest to William O'Brien State Park, weighted by size. Click a lake for its full water quality grade, fish species, and depth.
| Lake | County | Grade | Surface Area | Distance |
|---|---|---|---|---|
| Unnamed Lake | Washington | D | 1.8K acres | 4.9 mi |
| Square Lake | Washington | A | 203.05 acres | 4.7 mi |
| Big Carnelian Lake | Washington | A | 457.03 acres | 6.2 mi |
| Big Carnelian Lake | Washington | B | 457.03 acres | 6.4 mi |
| Forest Lake | Washington | C | 2.3K acres | 9 mi |
| Bone Lake | Washington | D | 221.45 acres | 6.6 mi |
| Little Carnelian Lake | Washington | A | 136.62 acres | 7.1 mi |
| Green Lake | Chisago | C | 1.8K acres | 11.3 mi |
Other Parks in the Area
- Interstate Park— State Park, 12.9 mi
- Interstate State Park— State Park, 13 mi
- Wild River State Park— State Park, 20 mi
- Afton State Park— State Park, 24.7 mi
Park location and metadata sourced from Wikidata. For trail maps, camping reservations, and current conditions, visit the official MN DNR page. Lake grades are derived from EPA Water Quality Portal data using Metropolitan Council standards.