As a Salt Marsh Sentinel you can help advance science from your own backyard.

All you need to do is spend about 30 minutes, once a year, standing on your dock and answering a brief questionnaire about what you see when you look out at the marsh. As a participant in this exciting new project, you will receive:
• A banner for your dock to showcase your participation in this study
• An annual report with an update on this exciting new initiative

Same time, same place, once a year for 30 minutes is all it takes to help us understand the health of our estuaries.

Make a difference now and for years to come by monitoring the marsh, and empowering the NSRWA to assess changes in the marsh over time. Your participation is needed over multiple years. NSRWA staff will place a few small markers (colored pushpins) on your dock floor to mark specific distances from the bank of the river.

Dr. Sara Grady, NSRWA’s Watershed Ecologist, will show you what to monitor, what information to gather, and how to record it. The data collected will be pooled together for analysis — the data are not associated with your dock. Instead the docks are used only as a viewing platform along the river to look for changes in the marsh. As a project participant you will need to collect data and record it on an NSRWA datasheet once a year between August and September, at low tide. That time of year is the peak growing season for marsh grasses.

Please call the NSRWA at 781-659-8168 to participate in this exciting new initiative.

Salt Marsh Sentinel Project Q&A

What is this project about?
Salt marshes grow along the banks of the North and South Rivers tidal estuaries. These grasses survive flooding on a semi-regular basis. The low marsh is flooded twice everyday while the high marsh is usually flooded only twice a month. As the sea level rises so does the area that is regularly flooded. This means that what has traditionally been flooded twice a day is now under water longer which causes changes in the marsh zones. The low marsh zone does not survive as well, and the low marsh grasses creep into high marsh areas—which are now getting flooded more often than twice a month. In other words, the marsh is creeping upland except that it is stopped by steep river banks and houses—the high marsh just doesn’t have anywhere to go.

Why should I sign-up?
You should sign-up to help ensure the health of our estuaries now and for years to come. As part of a New England wide effort, the North and South Rivers Watershed Association collects scientific data on local salt marshes to inform management decisions and broad policy efforts. With your help, we will be able to assess changes in the marsh over time. This information is essential to protect the estuary and the hundreds of creatures that make it their home.

Why study the salt marsh?
We are starting to see marsh change and loss along the North and South Rivers estuaries. Salt marshes serve important ecological functions. They protect our waters by absorbing nutrients from the land; offer nursery habitat and shelter for a variety of fish like striped bass, bluefish, and herring; and they provide food for birds, fish, and other creatures. Marshes also help sequester carbon—the newly coined “blue carbon,” which is another way of saying that marine plants help mitigate climate change.

Salt marshes are in peril. The major threats to the viability of local salt marshes are sea level rise, physical obstacles to marsh migration; over-flooding; pollution, nutrients from fertilizers; boat traffic and invasive species such as the green crab. As a result of these threats, the salt marsh loses its structure and starts falling apart.

How do I sign-up to participate?
Email NSRWA scientist Sara Grady, Ph.D. at to sign-up to participate in this project. You and Dr. Grady will then set a time to meet on your dock to talk about the information you will be collecting and to place the markers on the dock — about 30 minutes is all it takes to help protect our estuaries.
Thank you for your commitment to protecting our local waters and estuaries!


To sign up to be a Salt Marsh Sentinel, please contact Gabriela Silva at or 781-659-8168.