Tapps Lake Dike No 2a is a crucial structure located in Pierce County, Washington, designed to divert water from the White River. Constructed in 1911, this earth dam serves primarily for recreational purposes, with a maximum storage capacity of 20,000 acre-feet and a normal storage of 18,000 acre-feet. With a hydraulic height of 9 feet and a structural height of 9 feet, the dam spans 350 feet in length, creating a surface area of 2,570 acres.

Managed by the Washington Department of Ecology, Tapps Lake Dike No 2a is regulated and inspected regularly to ensure its safety and functionality. The dam is classified as having a high hazard potential, although its condition assessment as of February 2018 was deemed satisfactory. Despite its age, the structure has been well-maintained and meets regulatory guidelines, with emergency action plans in place and regularly updated.

Located in Auburn, Washington, Tapps Lake Dike No 2a falls under the jurisdiction of Congressional District 08 and is overseen by Representative Kim Schrier. With its vital role in water diversion and recreation, this dam serves as a testament to successful water resource management in the region, highlighting the importance of infrastructure for both environmental and recreational purposes in the face of changing climate conditions.