North Lake is a reservoir located in Dallas, Texas, 2 miles southeast of Coppell. The Cypress Waters business and residential development is on its southern side. The lake area was once a large bowl-like valley that was used for farming. Construction on North Lake Dam began in 1956 and the dam was complete in August 1957. Many of the trees where the lake …North Lake is a reservoir located in Dallas, Texas, 2 miles southeast of Coppell. The Cypress Waters business and residential development is on its southern side. The lake area was once a large bowl-like valley that was used for farming. Construction on North Lake Dam began in 1956 and the dam was complete in August 1957. Many of the trees where the lake was to be built were cut down, although a few small structures still exist. The reservoir was designed as a cooling reservoir for a Dallas Power and Light Company electric power plant. At that time, the City of Dallas, Texas annexed the land around the power plant and the lake.