Cranberry Lake Forest Education & Research Center


The Lake and Wetlands

Cranberry Lake is 190 acres of shallow water, with a mean depth of 5 feet and a maximum depth of approximately 10 feet. The lake is unique in the region with its east-west orientation, which does not follow the typical glacially caused southwest-northeast orientation of most lakes in the area. There is a total of approximately 4.6 miles of shoreline. Its water source comes from three unnamed tributaries plus marsh and bog drainage on the west end. There is one outflow, Cranberry Creek, located on the east end of the Lake. The creek flows east and south down through nearby Lake Limerick and then out to Oakland Bay and the Puget Sound. The Foundation owns and manages approximately 114 acres of the lake, along with approximately 40 acres of additional wetlands and 1.7 miles of streams. 

Although the lake is considered healthy in part due to its undeveloped status, it is not without is challenges. Two invasive plants, fragrant waterlily and, to a lesser extent, swollen bladderwort threaten the health of the lake. The narrow west end of the lake is already severely impacted by fragrant waterlily in particular, and it is becoming a more serious problem in the east end of the lake owned by the Foundation. Efforts to control the infestation are ongoing. 

Educational Opportunities

Come see the lake and creeks and test water quality. Look at the organisms that grow and live in the lake and how they related to water quality and the overall health of the system. Tour our boardwalk and see active beavers altering the landscape. Take in the unique landscape filled with rare plants found only in bog environments.