Full "Snow" Moon Night Hike @ The Refuge

February 6 at 6:00 pm
There is no such thing as bad weather, only bad clothes. So no more excuses! It's time to bundle up, get back outside, and feel the rejuvenating power of nature…

President's Day Hike @ The Refuge

February 20 at 1:00 pm
Celebrate this President's Day with a relaxing, family-friendly, guided tour of the Great Swamp National Wildlife Refuge's Orange Trail. The kids are off from school and it's a beautiful time…

Native Pollinator Plant Webinar Series

February 21 at 7:00 pm
Building a "Jersey-friendly yard" creates a healthy foundation of soil, conserves water, attracts and supports wildlife, and adds beauty and interest to your home landscape. Leading up to our 3rd…

All Upcoming Events

From hikes to educational workshops, GSWA offers a wide variety of environmentally focused programs. We'd love to have you join us at an upcoming event!
View All»

Land Stewardship

GSWA receives national accreditation and is one of only eight New Jersey groups to achieve this designation! GSWA’s vision supports the protection, preservation and promotion of NJ’s open spaces.

Read More

Things to See and Do

From hiking & biking, to horseback riding & kayaking, there are countless outdoor activities to enjoy in this area. What’s your adventure today in New Jersey’s great outdoors?


Eco-Friendly Living

Every individual home has an effect on non-point source pollution in our watershed. Use our interactive home guide to lean how you can minimize your impact and help keep our watershed healthy.



The Riverkeepers are the primary voice using the advocacy model to stand up for clean waterways. GSWA is proud to be the Passaic River Waterkeeper Alliance Affiliate, protecting the source to sea.

Read More

Featured Programs


In-School Education

GSWA is dedicated to teaching the younger generations about their impact on the watershed and river. Every year, we reach over 3,000 students through our in-school programming.


Water Quality

Every year, we publish a Water Quality Report Card about the prior year to help inform the public about the data we collect and the issues our watershed faces.

Report Card

New GSWA Video

The Passaic: One River, One Community

The Passaic: One River, One Community

Watch our new, 4-minute video that takes you on a journey down the Passaic River from its headwaters in Mendham to Newark Bay where the river meets the sea. Learn more about what we do, how we do it, and why we do it.
Watch Video

GSWA Partner Events


GSWA Partner Events

GSWA and its partners in our historic watershed and across the Passaic River region are excited to provide you with a listing of free-to-the-public environmental events happening locally.
For inclusion please contact
Read More


CMA sign

1 Tiger Lily Lane, Harding Township, NJ

An ecological gem, preserved from deer and invasive species

You’re invited to explore our Conservation Management Area (CMA) a wooded 73-acre natural area in Harding Township. Its 3.5 miles of boardwalk and mulched trails are open to the public for walking, hiking, and nature study.

Read More


2022 Spring Newsletter Cover3

GSWA Fall 2022 Newsletter

Community Organizes to Create the Mendham Alliance for Preservation and Conservation. By Frank Zammataro, Guest Author. Re-zoning sparks a call for transparency and balance in accelerated growth plan. What do you do when you hit a brick wall at Town Hall? “You get organized!” says Frank Zammataro…
Read More