This swim covers the entire length of Horsetooth Reservoir,  located in the foothills west of Fort Collins. Swimmers (and paddlers) start at Satanka Bay (north end) and swim to South Bay swim beach. The start is in the water, the finish may be in or out of the water, dependent on water levels.  The race committee will determine the finish location the week before the race, however last minute changes may be required depending on reservoir conditions.


To register, swimmers must meet the following requirements.

First Time Swimmers of the Horsetooth Open Water 10K Swim are required to obtain approval from George Thornton or Joe Bakel prior to registration (send email to

Swimmers should describe their experience in long distance open water swimming and how they will prepare to meet the challenges of swimming 10 kilometers at approximately 5400 feet (1700 meters) elevation, in 62 to 70° F (16 to 21°C) water.  Include a description of your nutrition plan during the swim.

First Time Swimmers between the ages of 14 and 19 who have not previously completed the Horsetooth Open Water 10K Swim are required to obtain approval and a parent or guardian must be in their escort watercraft.   Please contact the race committee at for additional details.


Swimmers must wear the race swim cap.

No MP3 players or similar devices are allowed.

All WOWSA  rules apply including swimsuit definitions. Exceptions and clarifications include:

Unlike many open water events, the Horsetooth 10K Open Water Swim allows no drafting except where unavoidable at the start. If flagrant drafting is observed, that swimmer will be disqualified.


WOWSA Marathon and Channel Rules state swimsuits shall not go beyond the end of the groin or shoulders.  The Horsetooth Open Water Swim allows the swimsuit to extend to the knees.


New in 2017.  There will be a limited number (20) wetsuit slots available.  Wetsuit swimmers will not be eligible for an “official” swim.  Wetsuit swimmers will not be eligible for awards.   Wetsuit swimmers must supply their own paddlers and craft (not eligible for organizer supplied paddler/craft)


Swimmers using organizer-supplied paddlers and first-time Horsetooth 10k swimmers must attend the check-in/orientation dinner on Saturday evening.  Swimmers who have swum the Horsetooth 10k before and are providing their own paddler may choose to attend the webinar or the dinner (or both!).  Attendance at one of the two is required in order to be receive any new safety information.

Everyone is allowed to attend the webinar, even if not required.

Support Craft

Every swimmer must be accompanied by a paddler (canoe, kayak, SUP) for the entire race.  The paddler provides visibility for safety, navigation, and nutrition.  For those without access to a paddler, the race committee makes available up to 25 paddlers (first come / first served).  Swimmers pay an extra fee for the use of the paddler and all of that fee is a donation to Team Wellness and Prevention.


First, second and third place men and women will receive a trophy.
A traveling trophy, The Turner Cup, is awarded to the first man and first woman finisher.

Pledge Program

Your registration fee is just one of the ways Team Wellness and Prevention raises money to fund programming.

We need your help to raise even more funds. Please create a donation page on FirstGiving and encourage friends and family to donate. Help us continue the fight against drug and alcohol abuse. Learn more about the pledge program.

Registration and Fees

Registration will open April 2018.

The registration fee covers safety (Dive Rescue, EMTs), t-shirt and awards. A significant portion is a donation in support of the Team Wellness & Prevention programs.

$110 – Registration fee

Registration ends August 17. No late or race-day registrations allowed.

$40 – Committee-provided paddler and craft

The swim committee will provide up to 25 paddlers, with craft, on a first-come, first-served basis for swimmers that request and pay.  A wait list will be established if more than 25 requests are received.  Send email to for more information.  Paddlers are volunteers and all of the $30 fee is a donation to Team Wellness & Prevention.

$5 – Each additional guest at the check-in dinner.

The swimmer and paddler each receive dinner as part of registration.  Family and friends are welcome to join you as additional guests.

If you plan to bring additional guests and didn’t register them, please email and let us know how many.  Please bring $5 cash/guest to the check-in at dinner.