An official website of the United States government.

We've made some changes to If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Lower Merrimack River

About the Lower Merrimack

On this page:


The Lower Merrimack River winds from Manchester, New Hampshire to Newburyport, Massachusetts, and provides drinking water for almost 600,000 people in five Massachusetts communities; Lowell, Methuen, Andover, Tewksbury and Lawrence, as well as Nashua, New Hampshire.

The Merrimack River's water power supplied energy for the textile industry's mill complexes during the 1800s from Manchester, NH to Lawrence, MA.

You can learn more about the River's past from an article from the National Park Service (PDF) (2 pp, 393 K, About PDF).

The river has many challenges as well as many dedicated stakeholders working to improve the water quality and the environment of the communities it passes through. With so many communities depending on the river for clean water for drinking water and recreation we want to makes sure the river is as clean as it can be.

Top of Page


This is a link to map of the watershed and sub watersheds of Merrimack. The map contains the National Hydrography Dataset (NHD) Hydrologic Unit Code (HUC) 8, 10, and 12 boundaries for the Merrimack River Watershed and city locations for the EPA water quality monitoring stations.

Here is a listing of all the communities that are included in each of the hydrologic unit code (HUC) boundaries (HUC_8_10_12_MRW_towns).

Top of Page