Public Notice

Subject: Stanford Treeathlon Event at Seal Point Park, San Mateo
Event Date: Saturday, February 14, 2026

Dear Neighbor,

The Stanford University Triathlon Team (SUTT) is writing to notify you of the Stanford Treeathlon at Seal Point Park in San Mateo on Saturday, February 14, 2026. This event is sanctioned by USA Triathlon (USAT) and serves as a community race and primary fundraiser for the Stanford Triathlon Team. The race will include a swim portion, a bike course, and a run course, based out of Seal Point. Treeathlon welcomes collegiate and community athletes, and is designed to be a safe, inclusive, and enjoyable event for participants and spectators alike.

Event Name: Stanford Treeathlon
Date: Saturday, February 14, 2026 (Set-up: February 13)
Time: 8:00 AM – 5:00 PM 
Location: Seal Point Park, San Mateo

Bike Course:
Four laps of a 2.4 km section along J. Hart Clinton Drive and East 3rd Avenue, from the intersection of Church Road to the intersection of Mariners Island Boulevard (westbound lanes).

Impact to Traffic: 
Access to all businesses, residences, and parks will remain open. Expect delays up to 15 minutes. J Hart Clinton Drive and East 3rd Avenue will remain open in eastbound direction during the event, however westbound traffic on J Hart Clinton Drive will be detoured between Mariners Island Blvd and Church Rd. The detour follows Mariners Island Blvd then Fashion Island Blvd then S. Norfolk St back to J Hart Clinton Dr.

These roads will remain open:

  • Detroit Drive

  • Anchor Road

  • Mariners Point Golf Center

 These parking lots will be closed to vehicles:

  • Ryder Parking Lot

  • Seal Point Parking Lot

  • Mariner’s Point Marsh Viewing Platform

The race location at Seal Point Park will remain open to the public and visitors can find alternative parking at Bayside Towers (4100 E 3rd Ave, Foster City, CA 94404) with a shuttle to Detroit Drive for accessing Seal Point Park. Moreover, limited street parking may be available along Mariner’s Island Blvd.

The Stanford Triathlon Team will coordinate closely with the City of San Mateo, San Mateo Police Department, and USA Triathlon officials to ensure public safety and minimize disruption to local traffic and park access. If you have any questions, comments, or concerns regarding this event, please contact the San Mateo Parks Special Events Department. 

We greatly appreciate your understanding and support as we host this community event. Our team values our relationship with the San Mateo community and is committed to maintaining clear communication and ensuring minimal impact on local residents and businesses.

Thank you for your time and consideration.

Sincerely,
Mathis Heyer, Bennie Hesser, Zander Opperman
Race Directors | Stanford University Triathlon Team

Email: treeathlon@gmail.com