Describe Your Event

Warning, this event was expired!

This open water swimming oasis has been the hottest venue in Colorado since our first open water swim back in 2016. Who’s ready for round 4? Don’t delay, last year we sold out in just a few months!

The course will be set up as a 1.2 mile out and back, with the option to swim two laps for a 2.4 mile swim. We’ll also have a 1/2 mile swim option for beginners! We’ll have refreshments and raffles post event as we post your times.

Please note that if you miss your chance to dive into the Rueter-Hess waters this July 31st you’ll need to wait a full year before getting another chance! This event is limited to just 200 athletes so don’t delay on registration, last year’s race sold out by March 1st!

DATE: Saturday July 31st, 2021

START TIME: The 2.4 mile swim will kick things off at 7:00am with the 1.2 mile swim starting at 7:10am, .5 mile swim starting at 7:20am

Wetsuits???  Wetsuits are not required, however most participants will wear them for warmth and for buoyancy. The water temp in the Rueter Hess Reservoir last season was 68 degrees!

RACE CUT-OFF: Swimmers in the 2 lap (2.4m) option must finish by 9:30am (2.5hr hard cut off)

PRE-REGISTRATION: The Parker Open Water Swim is open to all ages 10 and up and pre-registration closes on Sunday July 12th at midnight or when the event hits its 200 athlete capacity!

RACE DAY REGISTRATION: Race day registration opens at 6am unless that event has already sold out online! 

RACE FOR FREE: If you recruit a safety kayaker or stand up paddleboarder we’ll comp your entry.  For more info please e-mail  to sign-up and receive your free race credit!


$35 – Pre-Registration (.5 mile)

$40 – Race-Day Registration (.5 mile) *If not sold out                      

$37 – Pre-Registration (1.2 mile)

$42 – Race-Day Reg (1.2 mile) *If not sold out

$40 – Pre-Registration (2.4 mile)

$45 – Race Day Reg (2.4 mile) *If not sold out


Race Day Schedule – Saturday July 31st – Race Day!

6:00am-6:50am – Athlete check-in & race day registration

7:00am – 2.4 mile swim start

7:10am – 1.2 mile swim start

7:20am – .5 mile swim start

7:40 am- Results posted, post-race snacks, music & raffle prizes

9:30am – 2.4 mile swim cut off

Refund & Bad Weather Policy: Once accepted entry fees will not be refunded for any reason

Race Cancellation Information: We do not make any decision to cancel the race due to weather until shortly before the start on the of the event. We have set up a Twitter alert system so you will receive a message on your phone (if you are on Twitter) regarding conditions. 

​Dogs are not permitted at the Rueter Hess Reservoir; Not if your dog stays by your towel.  Not if your dog won’t bark or growl.   Not if your dog is on a rope. Not if you’re scared he might elope.  Not if your dog waits on the shore.  Please, NO DOGS AT THE RESERVOIR!


North America

Distances Offered






Swim Type


Water Type