Mason, also known as M-107, is a federal-owned dam located in Baker, Oregon, along the Powder River. Built in 1967 by the Bureau of Reclamation, Mason primarily serves the purpose of flood risk reduction and irrigation. The dam stands at an impressive height of 173 feet and has a storage capacity of 111,500 acre-feet, with a normal storage level at 78,500 acre-feet. The dam's high hazard potential underscores the importance of careful monitoring and maintenance.

Managed by the Bureau of Reclamation, Mason's design includes rockfill construction with an arch core type and a rock foundation. The dam spans 895 feet in length and covers a surface area of 2,235 acres, impacting a drainage area of 165 square miles. With a maximum discharge capacity of 1,210 cubic feet per second, Mason plays a crucial role in managing water resources and mitigating flood risks in the region. While the dam's condition assessment is currently not available, its last inspection in September 2020 and high hazard potential highlight the need for continued vigilance and emergency preparedness.

In the event of an emergency, it is essential for stakeholders to ensure that the Emergency Action Plan (EAP) is up to date and meets guidelines for effective response. With its strategic location and significant impact on the surrounding area, Mason's role in flood risk reduction and water management underscores the importance of ongoing monitoring and risk assessment. As a key asset in the region's water resource infrastructure, Mason serves as a testament to the critical role that dams play in safeguarding communities and ecosystems from the impacts of climate change and extreme weather events.