Coaches & Directors

Tri Valley Masters is here to support your needs. If your questions are related to workouts, meets, events, goal setting, and other swimming related needs, please contact one of the coaches. For all questions related to administrative, such as dues, safety, or policy issues, please contact one of the board members.

Coaching Staff

Mary Nygren

Head Coach


Mary has been involved with swimming for over 40 years, beginning as a youngster and continuing on up to Masters. She has been involved directly with Masters swimming and this team for over 25 years. She competed as a youth in distance freestyle and the I.M. events. Coach Mary is ASCA certified, a member of USA swimming as well as USMS.

Her emphasis on distance events as a youth has continued on in Masters. She enjoys participating in the open water events with swims including Trans Tahoe, Alcatraz, and the Golden Gate Bridge. She has placed in the top ten in her age-group in many of the open water and pool events. Her participation in swim meets includes several Masters Nationals, usually competing in the longer distance events.

Coach Mary began her coaching career by assisting with a variety of stroke clinics for Masters. The interaction with the swimmers and the range in swimming abilities inspired Mary to pursue coaching on a daily basis. She enjoys working with the diversity of swimmers that make up the members of Tri-Valley Masters. She also coaches an age-group USA team which allows her to keep current with all the latest swimming techniques. With her work with youngsters, she has coached the beginning swimmer up to the nationally ranked level. Stroke improvement is her goal in every workout no matter what age and ability she is coaching. She is known to give some great distance sets as well as challenging drill work with a friendly smile on her face! She was honored with the USMS Kerry O'Brien Coaches Award in 2014 for her dedication and commitment to TVM and the masters swimming community.

Daniel Ridosko

Assistant Head Coach


Daniel has been with Tri-Valley Masters for 20 years as a coach and swimmer. He is known to be a warm water swimmer but has competed in a few open water swims as well as pool meets. He began coaching in Europe and has been hooked ever since. Besides coaching with Tri-Valley Masters, Daniel coaches age-group swimmers with great success. He has had swimmers in the top ten locally and nationally. He has assisted with coaching several ranked USA National level swimmers as well as a World Record holder. Daniel has great knowledge in stroke mechanics and is very detail oriented when coaching. He enjoys working with all levels of swimmers and is very enthusiastic and passionate about swimming. He is ASCA certified, a member of USA swimming and USMS. Coach Daniel is known for his challenging workouts and a no excuses attitude.

He is a founder and CEO of   Tri Valley Aquatics . USA Swimming Age group team, quickly gaining reputation for it's quality of high end age group swimming.

Talia B Petit

assistant coach


Talia has been coaching with TVM since the early 2000's. She grew up locally and swam through high school. While in San Deigo for college, she discovered masters swimming. Upon her return to the area, she started as a swimmer with TVM and joined the coaching ranks while completing her masters degree. She has since started her teaching career and a family. She is the main coach of our Saturday practices. She always offers thoughtful, challenging workouts with a creative flair. 

Jen Sung

Assistant coach


Jenn is the newest addition to the coaching staff. She has competed in swimming through the college level. She has turned her focus to triathlons and is fond of running. She is a great resource for our triathlete community as well as our competitive swimmers. 

Board of Directors

Janet Kaehms

member at large


Tim J Reilly

Member at Large


Robyn L Toschi



Jorge I Angel