Saw Mill River Daylighting - The River in Context
Saw Mill River Daylighting
The River in Context
The River in Context
The Watershed
A watershed is the land, hills and slopes that drain rainfall to a river. The Saw Mill River watershed (marked in green on the map) includes parts of 12 municipalities. The river begins in a Chappaqua wetland approximately 20 miles north of Yonkers. It is also known by its Lenape name, "Nepperhan."
A tributary is a stream that flows to a larger stream. Tributaries make rivers "grow" by adding more water. The Saw Mill River tributaries include Tertia Brook, Nannyhagen Creek, Mine Brook, Rum Brook and others. The Saw Mill is also a tributary to the Hudson, and the entire Saw Mill River watershed is part of the Hudson River watershed. Place names often refer to rivers: Nepperhan Avenue, Rumbrook Road, Nepera Park. You are always in a watershed no matter where you go.
A Tidal Estuary
The tidal pool before you is actually a confluence-the flowing together of two streams or rivers. Here the Saw Mill River flows together with the Hudson tidewater. An estuary is the tidal mouth of a river where salt water from the ocean and fresh water from tributaries mix and mingle. Estuaries have high levels of nutrients and are among the most productive habitats in the world.
The Hudson River estuary extends from the Atlantic Ocean north to the Federal Dam at Troy (north of Albany). From where you stand, you can see high tide twice a day. The Hudson River has tides varying in height from 1 foot below to 5 feet above sea level. The Mahican name of the Hudson River, "Muhheakantuck," means "river that flows both ways."
You are standing in two watersheds, at the mouth of a tributary, at the confluence of two rivers, next to a tidal estuary.
Environmental Stewardship
Almost anything you leave on the ground or in the gutter-plastic bottles, pet waste and litter-will be washed into the river with rain. This stormwater pollutes the river not only where you live, but also downstream.
If someone throws a plastic water bottle along the South County Trailway in Hawthorne, it will eventually wash downstream to Yonkers and out to sea.
In fact, a huge island made of plastic trash is continuing to grow in the Atlantic Ocean area called the Sargasso Sea-where the American eel spawns. This island of trash covers a north-south dimension roughly the distance between Virginia and Cuba!
Do your part: keep trash where it belongs, in a trash can; only use fertilizers and pesticides in moderation, and not before a rainfall; pick up after your pet.
Interpretive signs developed for the City of Yonkers by Groundwork Hudson Valley, Friends of Philipse Manor Hall, Yonkers Historical Society and Yonkers Public Library. Park funded by City of Yonkers, NYS Department of Environmental Conservation, NYS Dormitory Authority, Empire State Development, NYS Environmental Facilities Corporation, US Environmental Protection Agency, and Hudson River Foundation.
Submitted by @lampbane
Submitted by @lampbane