Snapshot Day is the oldest and largest single-day annual water quality monitoring event in California.

On the first Saturday in May each year hundreds of volunteers join the Coastal Watershed Council and Monterey Bay National Marine Sanctuary staff to take a “snapshot” of the health of rivers and streams flowing into the Sanctuary. This favorite event draws people of all ages from all over California’s Central Coast to collect scientifically valid water quality data and to learn more about their local watersheds. Data from field measurements and lab analysis are collected and analyzed to determine the biggest threats to water quality and best management practices to address them.

Saturday, May 1st, 2021

During normal non-COVID Snapshot Days, we hold multiple trainings for new volunteers over the course of the week prior to the event, but this year due to COVID, Snapshot Day training will only be available online. As a result, the training will be a refresher for those who have participated in past Snapshot Days or other water quality monitoring activities such as First Flush, Urban Watch or other monitoring activities. On the first Saturday in May, volunteers will collect field measurements and water samples from creeks and rivers that flow into Monterey Bay National Marine Sanctuary that are tested for bacteria, nitrate and phosphate. Monitoring results will be analyzed by Sanctuary staff and shared with our community members and leaders to increase awareness and action for cleaner water.

If you are interested in joining Snapshot Day this year, register using the link below, contact Lisa Emanuelson from the Monterey Bay National Marine Sanctuary with any questions, and save the dates for the online refresher training on Thursday, April 22 from 6:00 pm to 7:30 pm. and Snapshot Day water quality monitoring on Saturday, May 1 from 8:30 am to 12:30 pm. For COVID safety, we are encouraging members of the same household or families to sign up as a team this year but with so many people getting vaccinated, if you are ok being on a team with people not from your same household let us know. However, we do expect team members from separate households to drive to the sites in separate cars. And as usual, masks will be required.

Register for Snapshot Day 2021


Schedule of Events
Thursday, April 22 from 6:00 pm to 7:30 pm: Online Training
Saturday, May 1 from 8:30 am to 12:30 pm: Snapshot Day Water Quality Monitoring Activities

Please direct any questions, or let us know if you cannot make the April 22nd training to:
Lisa Emanuelson (she, her, hers)
Volunteer Monitoring Coordinator, California Marine Sanctuary Foundation I Monterey Bay National Marine Sanctuary
(831) 521-9512

“When I first heard about Snapshot Day in early 2003 my son and I signed up to volunteer – he was interested in playing in creeks and I was looking to pass on my adoration of the outdoors to my family. Our baby Natalie soon joined the family and my wife and daughter both came along to the next Snapshot Day. Circumstances moved us away from Santa Cruz to the Chico area, but year after year we made the family trip down to Santa Cruz for Snapshot Day. Little did I realize how “our baby” Natalie would take to monitoring like she was born doing just that. In 2015, Natalie was even interviewed on the news at Snapshot Day! She will never forget that experience. I cannot tell you how proud I am of both of my children to be volunteers with CWC and how willing and caring they are to travel 250 miles each way in order to help others keep their water clean.”

— Gary Smith and his daughter Natalie

Dig in!

In two decades of water quality monitoring on California’s Central Coast, we’ve collected a lot of data. You can dig in to some of this data in the reports below.