Lake Mayfield is a reservoir

Reservoir

A reservoir , artificial lake or dam is used to store water.Reservoirs may be created in river valleys by the construction of a dam or may be built by excavation in the ground or by conventional construction techniques such as brickwork or cast concrete.The term reservoir may also be used to...

 located near Mossyrock, Washington

Mossyrock, Washington

Mossyrock is a city in Lewis County, Washington, United States. The population was 759 at the 2010 census.-History:The city began as a trading post named Mossy Rock in 1852, after a high moss-covered rock at the east end of Klickitat Prairie...

, in Lewis County

Lewis County, Washington

Lewis County is a county located in the U.S. state of Washington. As of 2010, the population was 75,455. The county seat is at Chehalis, and its largest city is Centralia....

. It was created by Mayfield Dam on the Cowlitz River

Cowlitz River

The Cowlitz River is a river in the state of Washington in the United States, a tributary of the Columbia River. Its tributaries drain a large region including the slopes of Mount Rainier, Mount Adams, and Mount St. Helens....

. The lake contains an island with a lighthouse.

The Cowlitz River Arm is significantly colder than the rest of the lake due to its proximity to the Riffe Lake which is created by Mossyrock Dam. The water from Riffe Lake flows through the Mossyrock Powerhouse's two hydroelectric generators. The Tilton River arm is much warmer and shallower due to past landslides. The Tilton River area is often referred to as 'Wally World'.

Throughout the 1980s and 90s there were many water ski and wake board tournaments held on the lake's Winston Creek arm where the Lake Mayfield Resort was located.