Nature-themed Holiday Cookies - Make & Decorate

November 29 at 6:00 pm
Jump-start on your holiday baking during this DIY cookie workshop. It's sure to put you in the holiday spirit. First you will channel your inner artist by decorating pre-baked, nature-themed…

DIY Winter Wreath Workshop

December 8 at 5:00 pm
It's not winter until the wreath is on the door. Put on your warm clothes and come craft a homemade winter wreath made from native evergreens and other native plants.…

Winter Solstice Night Hike & Story Telling

December 21 at 6:00 pm
Bundle up and let's celebrate the first day of winter (winter solstice) with a crisp, invigorating night hike and storytelling at Jockey Hollow. Winter solstice is the day with the…

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!
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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.

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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.

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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.
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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
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Featured Event

Winter Solstice Hike_website

Celebrate the First Day of Winter on Dec. 21 for a Night Hike & Story Telling

Bundle up and let’s celebrate the first day of winter (winter solstice) with a crisp, invigorating night hike and storytelling at Jockey Hollow. Winter solstice is the day with the fewest hours of sunlight in the whole year, making it the shortest day of the year. With the new moon just 2 days away, the stars in the winter skies will be shining brightly…
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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…
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