The Mystic Lakes, consisting of Upper Mystic Lake and Lower Mystic Lake, are closely linked bodies of water in the northwestern suburbs of

Boston Boston (), officially the City of Boston, is the state capital and most populous city of the Commonwealth of Massachusetts, as well as the cultural and financial center of the New England region of the United States. It is the 24th- mo ...

Massachusetts Massachusetts (Massachusett language, Massachusett: ''Muhsachuweesut assachusett writing systems, məhswatʃəwiːsət'' English: , ), officially the Commonwealth of Massachusetts, is the most populous U.S. state, state in the New England ...

. The lakes lie at an elevation of 1 meter above sea level, within the towns of

Winchester Winchester is a City status in the United Kingdom, cathedral city in Hampshire, England. The city lies at the heart of the wider City of Winchester, a local government Districts of England, district, at the western end of the South Downs Nation ...

, Arlington, and

Medford, Massachusetts Medford is a city northwest of downtown Boston on the Mystic River in Middlesex County, Massachusetts, United States. At the time of the 2020 U.S. Census, Medford's population was 59,659. It is home to Tufts University, which has its campus alo ...

. Upper Mystic Lake is fed by the

Aberjona River The Aberjona River is a ,U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map, accessed April 1, 2011 heavily urbanized river in the northwestern suburbs of Boston, Massachusetts. The name is from the ...

, and drains south, over the

Mystic Dam The Mystic Dam (and its gatehouse) are a historic dam and gatehouse between Lower and Upper Mystic Lakes in the suburbs north of Boston, Massachusetts. The dam was built in 1864–65 by the Charlestown Water Commission (Charlestown then being ...

, into Lower Mystic Lake, which in turn empties into the

Mystic River The Mystic River is a riverU.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed April 1, 2011 in Massachusetts, in the United States. In Massachusett, means "large estuary," alluding to t ...

and then

Boston Harbor Boston Harbor is a natural harbor and estuary of Massachusetts Bay, and is located adjacent to the city of Boston, Massachusetts. It is home to the Port of Boston, a major shipping facility in the northeastern United States. History Since ...

Description

Lower Mystic Lake is a

meromictic lake A meromictic lake is a lake which has layers of water that do not intermix. In ordinary, holomictic lakes, at least once each year, there is a physical mixing of the surface and the deep waters. The term ''meromictic'' was coined by the Austri ...

, which means that the lake has a deep layer of water that rarely, if ever, mixes with its top waters. As a consequence, the sediments at the bottom of Lower Mystic Lake accumulate in annual layers (or

varves A varve is an annual layer of sediment or sedimentary rock. The word 'varve' derives from the Swedish word ''varv'' whose meanings and connotations include 'revolution', 'in layers', and 'circle'. The term first appeared as ''Hvarfig lera'' (var ...

) that have been nearly undisturbed for a thousand years. Such varves in meromictic lakes preserve a historical record somewhat like tree rings do. In the case of Lower Mystic Lake, the varves have been used by Mark Besonen and his collaborators to study the historical incidence of hurricanes. Although the Mystic Lakes are popular for swimming, sailing, and fishing, the Upper Mystic Lake suffers from contamination by

arsenic Arsenic is a chemical element with the symbol As and atomic number 33. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. Arsenic is a metalloid. It has various allotropes, but ...

and other heavy metals from the

. The eastern shore of the lakes is part of the

Mystic River Reservation The Mystic River Reservation is a publicly owned nature preserve with recreational features located along the Mystic River in the towns of Winchester, Arlington, Medford, Somerville, Everett, and Chelsea in eastern Massachusetts. The reserve ...

managed by the Massachusetts

Department of Conservation and Recreation The Department of Conservation and Recreation (DCR) is a state agency of the Commonwealth of Massachusetts, situated in the Executive Office of Energy and Environmental Affairs. It is best known for its parks and parkways. The DCR's mission is ...

. The lakes were previously part of the drinking water supply for Charlestown and later Boston (see

Massachusetts Water Resources Authority The Massachusetts Water Resources Authority (MWRA) is a public authority in the Commonwealth of Massachusetts that provides wholesale drinking water and sewage services to certain municipalities and industrial users in the state, primarily in th ...

History

In the 1600s, the

Squaw Sachem of Mistick Squaw Sachem of Mistick (c. 1590-1650 or 1667) was a prominent leader of a Massachusett tribe who deeded large tracts of land in eastern Massachusetts to early colonial settlers. Squaw Sachem was the widow of Nanepashemet, the Sachem of the Pawtuc ...

, who deeded much of the land in Greater Boston to settlers, resided near the Mystics Lakes. Her

Naumkeag Naumkeag is the former country estate of noted New York City lawyer Joseph Hodges Choate and Caroline Dutcher Sterling Choate, located at 5 Prospect Hill Road, Stockbridge, Massachusetts. The estate's centerpiece is a 44-room, Shingle Style c ...

band likely established fishing weirs at the outlet of the lake and the downstream Mystic river, and had grown corn on the lake's eastern shores. An indigenous burial site from the 1600s, possibly of sachems

Nanepashemet Nanepashemet (died 1619) was a sachem and ''bashabe'' or great leader of the Pawtucket Confederation of Abenaki peoples in present-day New England before the landing of the Pilgrims. He was a leader of Native peoples over a large part of what is ...

or Montowompate, was discovered in 1862 just east of the Mystic lakes and was memorialized as Sagamore Park. From 1803 to 1851, the

Middlesex Canal The Middlesex Canal was a 27-mile (44-kilometer) barge canal connecting the Merrimack River with the port of Boston. When operational it was 30 feet (9.1 m) wide, and 3 feet (0.9 m) deep, with 20 locks, each 80 feet (24 m) long and between 10 and ...

, a progenitor to the

Erie Canal The Erie Canal is a historic canal in upstate New York that runs east-west between the Hudson River and Lake Erie. Completed in 1825, the canal was the first navigable waterway connecting the Atlantic Ocean to the Great Lakes, vastly reducing t ...

, operated on the eastern shore of the Mystic Lakes, connecting Lowell to Charlestown.

References

{{authority control Arlington, Massachusetts Winchester, Massachusetts Medford, Massachusetts Meromictic lakes Mystic River Lakes of Middlesex County, Massachusetts Lakes of Massachusetts