Texas Water
2:52 pm
Fri November 22, 2013

Lake Fork role in Dallas water plans to increase

Lake Fork, which sits about 90 miles east of Dallas, will play an increasing role in meeting the water needs of the city and its thirsty, rapidly growing suburbs.

A report in the Nov. 19 Rains County Leader details the short-term and long-term plans to use Lake Fork water in the metro Dallas area, which were discussed at a meeting Of the lake Fork Sportsman Association on Nov. 12 in Emory.

20K acre-feet withdrawal pending pump completion

The short-term plans involve the use of up to 20,000 acre-feet per year of the lake’s water as soon as new pump stations are functional. The North Texas Municipal Water District has rights to 20,000 acre-feet annually of the Sabine River Authority’s share of Lake Fork water, according to Ken Del Negro, who spoke at the meeting in Emory. Del Negro is an assistant director of water Production at Dallas Water Utilities.

The North Texas district, which serves the northern suburbs of Dallas, has had a contract for the allocation, but has not had a way to move the water to one of its reservoirs. The new pump stations would move water from Lake Fork to Lake Tawakoni, from where water would be moved to Lake Lavon, which serves North Texas Municipal Water District customers, Del Negro said.

Dallas Water Utilities, which serves the city itself, has entered into agreements this year helping the troubled North Texas Municipal Water District, based in Wylie.

The infrastructure that would take water from Lake Fork to Lake Tawakoni is that of Dallas Water Utilities. Lake Fork began supplementing Dallas’ water supply in 2010.

Tough times for North Texas district

The explosion of suburbs and exurbs north of Dallas has strained the North Texas Municipal Water District’s resources, which include Lake Lavon as well as parts of Lake Jim Chapman and Lake Tawakoni.

In addition to the increased demand, the North Texas district has had to deal with the effects of the ongoing, multi-year drought. Also, the district has had to manage the loss of the use of Lake Texoma, which until 2009 supplied 28 percent of the district’s water.  An infestation of invasive zebra mussels in that reservoir has complicated the process of treating lake water for municipal use.

Texoma might remain out of the picture until at Spring 2014, when the district hopes to finish construction on a pipeline extension that will bring water from Texoma directly to the district’s treatment plant in Wylie.

Federal officials ordered the North Texas district to stop using Texoma water in 2009 in response to the zebra mussel problem. Officials wanted to block the spread of the pests into the Trinity River Basin. The North Texas district had used a combination of pipes and Sister Grove Creek to move Texoma water to Lavon Lake for storage. The district is now nearing completion of a system that will pump Texoma water directly into the treatment plant.

To help the North Texas district get through its Texoma-deprived period, the Dallas Water Utility has recently entered into a three-year contract to moved up to 18 million gallons of water daily into Lake Tawakoni, a resource shared by the two districts. 

Use to increase in 2025

Once the North Texas district is able to get Texoma water back into the mix, the district might – or might not – continue to exercise its right to withdraw up to 20,000 acre-feet annually from Lake Fork. A worst-case scenario – meaning continued drought and maximum withdrawals by the North Texas district – could result in a drop of less than one foot per year of Lake Fork’s level, Del Regno said.

Meanwhile, Dallas Water Utilities plans to begin drawing on Lake Fork regularly around 2025, based on demand projections, according to the Rains County Leader’s report of Del Regno’s presentation in Emory.

Dallas Water Utilities has rights to up to 74 percent of Lake Fork’s available water, which is 132,000 acre-feet per year. The lake yields 188,600 acre-feet per year. The Dallas utility purchased those rights from the Sabine River Authority in 1981 for $105 million, Del Regno said.

Lake Fork is not a preferred source for Dallas, as the long distance and the water’s low alkalinity both add to the costs of delivery and treatment, Del Negro said.

Construction of Lake Fork began in 1975 and was completed in 1980.