Nonacoicus Brook
Nonacoicus Brook
- 1.4 miles in length
- Flows east to west
- Part of the 538 square mile Nashua River Watershed
- Located within the Squannassit ACEC (Area of Critical Environmental Concern)
- Receives its water from Plow Shop Pond and less than a mile further downstream, from Willow Brook flowing north from Devens
- Empties into the Nashua River
- Linked to Bowers Brook, that flows into Grove Pond, after which it is renamed Nonacoicus Brook downstream when discharged from Plow Shop Pond
- All of Nonacoicus Brook north of West Main Street is designated as Priority Habitat by the Massachusetts Natural Heritage and Endangered Species Program (NHESP)
- Part of the brook is part of the Oxbow National Wildlife Refuge
And if you want to learn more…
General Description and History
Nonacoicus Brook is the final link in the chain of hydrologically-connected ponds and streams that bisect Ayer and eventually convey their waters into the Nashua River: Long Pond > Sandy Pond > Flannagan Pond (fed into also by Pine Meadow Pond) > Balch Pond > Grove Pond > Plow Shop Pond > Nonacoicus Brook > Nashua River.
The brook is a low-gradient stream that flows through woods and wetlands, winding and curving its way under roads and railroad tracks until it reaches the Nashua River. It is the main route for drainage heading west in the Town of Ayer. The ‘Valley of Nonacoicus Brook’ is presumed to have been the primary east-west trail route through the area by indigenous Native American peoples prior to European settlement during the colonial period. During the 1700s, saw and grist mills were located along the brook back when the Ayer was still part of Groton plantation land.
The area that would become the Town of Ayer (officially in 1871 when it separated from Groton) was initially inhabited by the Nashaway Native Americans. The Nashaway were a Nipmuck people (part of the Algonquian North American native language group) who inhabited the lands along the Nashua River and its tributaries, including Nonacoicus Brook. ‘Nonacoicus’ had multiple alternate spellings, but likely derives from Nunnacoquis, signifying “a small dry earthen pot,” – perhaps referencing a series of small mounds along the banks of the brook.
Because of the hydrological connectivity with in this chained water system, Nonacoicus Brook also receives impacted runoff from the former Fort Devens military base that was designated a superfund site in 1989 by the federal Environmental Protection Agency. Since heavy metals such as arsenic were once allowed to contaminate Grove Pond and Plow Shop Pond by way of runoff from the Fort and other local industries (i.e. the Tannery that used to operate on Plow Shop Pond and burned down in a large fire in 1961), Nonacoicus Brook has been affected as the downstream recipient of their waters.
Trophic Status
Unknown
Impairment
The Federal Clean Water Act (effective in 1972) governs water pollution in the United States, and requires states to identify waterbodies that do not meet EPA standards and are designated as “impaired.” In the most recent report, Nonacoicus Brook is listed as a Category 5 impaired waterbody, primarily due to the low level of Dissolved Oxygen (DO). DO is a measure of how much oxygen has dissolved in the water and therefore is available for fish, zooplankton, and other aquatic organisms that need this oxygen in order to survive. The level of DO is therefore indicative of the water quality and health of a waterbody. Low DO levels indicate poor/impaired water quality.
This sign project was funded by a community grant from the Nashua, Squannacook, and Nissitissit River Wild & Scenic Stewardship Council.