That Dam Half & 5K

Saturday, October 19, 2019 • Granbury, TX • Course Map

Note: The course description depicts the old course in Grand Prairie. We’ll update with the new location’s info when it’s available.

Set for its 4th annual running this fall on the trails that wind along the northern edge of Joe Pool Lake, That Dam Half Marathon & 5K takes runners on an out-and-back route that starts and finishes in scenic Lynn Creek Park, a 785-acre park that lies on the lake’s northern shore.

Organizers say it’s the “best time of the year for running in Texas,” and they’re likely right thanks to the cooler temperatures that October brings in the Dallas-Fort Worth metroplex area.

From the starting line in the parking lot where the park’s annual holiday Prairie Lights festival is held — one of two main festivals that take place in the park each year — runners make their way along the park roads and trails that wind through it, skirting the edge of the lake around the mile 1 marker.

After that, the course heads out onto Lynn Creek Parkway and then the Northside Impoundment Trail, a wide gravel road trail built along the berm that forms the lake’s dam. Runners make their way all the way to the other end of the 3-mile-long trail, running to the turnaround just north of Cedar Hill State Park and back.

Once they make their way back across the dam and back into Lynn Creek Park, there are some additional miles inside the park before runners cross the finish line back where they started, in the parking lot where Prairie Lights is held.

Runners will have 4 hours to complete the half marathon, organizers note, and they can expect an almost all-flat course thanks to its location along the dam — most of the course features little elevation change, except for the stretch around the middle of the race.

From the race organizers regarding the postponement:

“Access to the Lynne Creek Park dam has been closed by the Army Corps of Engineers until further notice. This Dam is a vital part of our course, and its closure requires a new course and location for That Dam Half.  As hard as we have tried to find another Dam and put on this race this year, it is just not meant to be.

That being said, with safety as our number one priority and fun as our 2nd, we have searched far and wide and have found the perfect spot.  It will take us some time to give you the experience that you deserve.  That Dam Half will be returning in 2019, and it will be better than ever!”

Photo courtesy That Dam Half

Photo courtesy That Dam Half

Race Weather & Climate

Located about 35 miles southwest of Fort Worth, Granbury typically sees some of its mildest and wettest weather of the year in October, which brings temperatures that average between the upper 50s and upper 70s and rainfall amounts just over 4 inches, which makes October the city’s rainiest month of the year.

On race day (Oct. 19), the average low is 52ºF and the average high is 78ºF.

Past Results

Course Map

See the race route map for That Dam Half here.

Starting Time

  • 7:30 AM – half marathon, 10K
  • 7:35 AM – 5K


  • $70 – $115 for the half marathon
  • $45 – $65 for the 10K
  • $35 – $55 for the 5K


To reserve your spot in the 2019 running of Grand Prairie’s That Dam Half or 5K race, register online at GetMeRegistered here.

Official Race Website

Facebook Conversations

Ever run in That Dam Half? Share your impressions here, as well as anything you learned about the race that you think other runners/walkers should know.