Your water. Your environment. Your voice.


  • What is a watershed?
    A watershed is an area of land that drains into a particular body of water, such as a stream, river, pond or lake. A watershed is not determined by political boundaries, but instead is shaped by nature’s hills and valleys.

  • Do we really drink water from the Stony Brook or Millstone River?
    If you live in central New Jersey your water likely comes from the lakes, streams, rivers and groundwater in the Stony Brook-Millstone Watershed, or a combination of these sources, supplemented by water from the Raritan River and reservoirs in the Highlands.

    In the Stony Brook-Millstone Watershed all streams, rain and snowmelt go to the Millstone River. The Millstone River starts in Millstone Township, Monmouth County and flows north joining with the Stony Brook in Princeton, Mercer County. It ultimately connects to the Raritan River in Franklin Township and Manville Borough, Somerset County. Some of that water is withdrawn from the river at that point, treated and then piped into homes and businesses throughout central New Jersey.

  • Do I live in the Stony Brook-Millstone Watershed?
    The Stony Brook-Millstone Watershed spans five counties and 25 towns. See our map to learn more about the region we cover.

  • What does the Stony Brook-Millstone Watershed Association do?
    The Watershed Association protects clean water and the environment throughout the Stony Brook-Millstone Watershed. Founded in 1949, we are one of central New Jersey’s first environmental groups. We protect clean water and the environment through a combination of conservation, advocacy, science and education.

  • Where is the Watershed Reserve and what can I do there?
    The 930-acre Watershed Reserve is located at 31 Titus Mill Road, Pennington NJ and is open dawn to dusk. It offers more than 10 miles of hiking trails and features the Watershed Center for Environmental Advocacy, Science and Education and Kate Gorrie Butterfly House. The butterfly house is open from early June through early October, dawn to dusk. Teacher-Naturalist led tours of the butterfly house occur throughout the summer – check our events page for dates and times. Appointments to visit the butterfly house on your own are not needed.

  • When is the Watershed Center open?
    The Buttinger Nature Center has been replaced with the new Watershed Center for Environmental Advocacy, Science and Education! We are open to the public Monday to Friday from 9:00AM – 5:00PM as well as Saturdays and Sundays from 10:00am – 4:00pm. All of our educational programs, including Watershed Nature Camp, and the Nature Shop operate out of the Watershed Center.

  • Can I bring my dog for a walk on the trails?
    Dogs are allowed on our trails and must be leashed at all times. Our trails are for foot traffic only (bikes, horses and ATVs are not permitted). Pets are not allowed in any buildings. Smoking or lighting of fires is prohibited on the Reserve, and picnicking is allowed in designated areas where there are tables (trash is carry in, carry out). Please do not remove or introduce any wildlife or plants into the butterfly house or from the Reserve. For maps and more information, click here.

  • Who should I call if I have an environmental problem in my town?
    If it is an environmental emergency, first call the New Jersey Department of Environmental Protection’s hotline at 1-877-WARN-DEP. Then call us and let us know about the problem. Visit our Staff page for a breakdown of our staff by department.



Woodcock Watch

Saturday, March 4, 6:00-7:30PM, Adults & Families (children 6yo+), Free

Join Education Director Jeff Hoagland at dusk as we watch and learn more about the spring courtship dance and fascinating life of this bird. Hike is co-sponsored by Washington Crossing Audubon Society.Call or email to register.

Learn more about all our programs for the coming weeks!

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