Ray Hubbard Lake is formed by an earthfill dam some 12,500 feet long.

Lake Ray Hubbard was filled by the construction of the Rockwall-Forney Dam on the East Fork of the Trinity River. The project, originally known as "Forney Lake," was initiated by the City of Dallas in 1964 to create a reliable water reservoir for the growing North Texas region. The river was officially impounded in 1968 when the dam gates were closed, allowing the natural flow of the East Fork Trinity River and its tributaries to flood the basin. It took approximately two years for the water to reach its maximum design extent, covering over 22,000 acres by 1970. Before the area was flooded, it was a densely wooded basin known locally as "The Bottom." While the city initially intended to clear all the timber, they ultimately left many trees standing in the north end; these submerged trees now provide a rich habitat for the lake's famous bass and crappie populations, making it one of the premier fishing spots in Texas today.

Excellent question! The filling of Lake Ray Hubbard is a fascinating story of engineering and water management in Texas. It wasn’t filled by a single, dramatic event, but rather through a controlled, multi-year process using the natural flow of the East Fork of the Trinity River.

Here’s a breakdown of how they did it:

1. The Dam and Reservoir Project

• Purpose: The lake was created primarily for water supply, flood control, and recreation. It is a key reservoir for the North Texas Municipal Water District (NTMWD) and the City of Dallas.
• Construction: The dam (an earth-fill embankment dam) was built between 1964 and 1968 across the East Fork of the Trinity River, near the community of Rowlett.
• Original Name: It was initially named “Forney Lake” after a nearby town, but was renamed in 1971 for former Dallas mayor and civic leader Ray Hubbard.

2. The Filling Process: Impoundment

The primary method was impoundment. Once the dam’s gates were closed, it began to block and capture the natural flow of the East Fork Trinity River and its tributaries (like Muddy Creek and Cottonwood Creek).

• No Massive Water Transfer: They did not pump in water from other major sources like the nearby Lake Lavon or the main Trinity River. The filling relied on rainfall and runoff from the lake’s 489-square-mile drainage basin.
• Timeline: The impoundment began in 1968. Due to variable North Texas weather, filling the lake to its “conservation pool” (the normal, usable level) took several years.
• Key Milestone: The lake officially reached its conservation elevation of 435 feet above sea level in 1974. This is considered the date it was “full” for practical purposes.