June 1 - August 24th • Every Tues & Thurs • 6AM - 8AM
About Open Water Swims at Boulder Reservoir
What: Swimming on a special volunteer-lifeguarded and protected course during summer wake-free mornings in Boulder, CO
Where: Boulder Reservoir
When: Tuesday & Thursday mornings until August 24 (except July 4)
6:00 AM: Reservoir gates open
6:15 AM: Check-In begins
7:20 AM: Last opportunity to start a new lap
7:40 AM: Everyone must be out of the water
Who: Adult (18+ years) only. BAM members and drop-ins welcome. Perfect for endurance swimmers, triathletes, fitness swimmers, and anyone that wants to swim outdoors outside of a pool. Training for a triathlon? Come and get comfortable swimming outside with others on a marked course. We welcome those who are not yet comfortable in the open water, and our course has a shorter option for those who want to stay close to shore.
For safety purposes, everyone must check in before entering the water every session, and everyone must check out after exiting the water before leaving the beach every time.
How: You don't need to be a BAM member to swim. However, you must sign our open water waiver before swimming the first time.
To drop in: Come to the Reservoir entry gate at or after 6:00 on the morning of the swim. Pay the gate entry fee. Proceed to the BAM check in table. There you will be given a waiver to sign and will pay the drop in fee ($10). Alternatively, you can buy an open water punch pass for $70, valid for any 10 BAM open water swims this summer (does not carry over to next year).
You may also become a member of BAM. The advantages of doing so are you can pay for your pass and sign the waiver ahead of time online. You will also be able to participate in BAM's coached pool swims all summer, if you sign up for one of our memberships, such as the Summer Pass or the regular (pool) Drop In or Punch Pass.
To sign up for BAM:
3. Pick a pass option (Open Water Drop In, Open Water 10-Punch Pass, and Summer Pass are the recommended options).
4. Book your workout (only necessary for pool swims)
Check out our FAQ that covers any of your nagging curiosities.
Start / Finish Zone
The course leaves from the west side of the swim beach & the reservoir's event building.
See which next open water session will work for you, or find a pool workout too!
Our swims are at the Boulder Reservoir 5565 51st St, Boulder, CO 80301
All swimmers must check in and out at our registration table before entering and after exiting the water.
Air and Water
Minimum air temp at 6am:
Minimum water temp at 6am:
Now Accepting Open Water Swim Volunteers
Join our volunteer crew of highly compassionate and dedicated volunteer lifeguards and registration table members. Our open water summer swims are not possible without our volunteers, and we cover the cost of each of our volunteer's valuable lifeguard certification.
Please fill out this form to learn more, this form is not a firm commitment, but we do request serious inquiries only.