{{Short description|Lake in New Hampshire, United States}} {{Use American English|date=July 2025}} {{Infobox lake | name = Mascoma Lake | image = lakemascoma.jpg | caption = Mascoma Lake, February 2005 | image_bathymetry = | caption_bathymetry = | location = Grafton County, New Hampshire | coords = {{coord|43|37|20|N|72|8|27|W|type:waterbody_region:US|display=inline,title}} | type = | inflow = Mascoma River; Knox River | outflow = Mascoma River | catchment = | basin_countries = United States | length = {{convert|4.2|mi|abbr=on}} | width = {{convert|0.7|mi|abbr=on}} | area = {{convert|1165|acre|km2}} | depth = {{convert|30|ft|abbr=on}} | max-depth = {{convert|68|ft|abbr=on}} | volume = | residence_time = | shore = | elevation = {{convert|228|m|abbr=on|order=flip}} | islands = Wood Island; Relhan Island; North Island | cities = Enfield; Lebanon (village of Mascoma) <!-- Map --> | pushpin_map = New Hampshire#USA | pushpin_label_position = | pushpin_map_alt = Location of Mascoma Lake in New Hampshire, USA. | pushpin_map_caption = <!-- Below --> | website = | reference = }} [[File:Mascoma Lake.jpg|thumb|MASCOMA LAKE, ENFIELD, N.H.; ca. 1906; Enfield Shaker Museum]] '''Mascoma Lake''' is a {{convert|1158|acre|adj=on}}<ref name=NHFG/> lake in western New Hampshire, United States. Most of the lake is within the town of Enfield, while a small portion is within the city of Lebanon, where it drains into the Mascoma River, a tributary of the Connecticut River.
The lake's general trend is from southeast to northwest, with the outlet at the northwestern end. The Mascoma River enters the lake near its halfway point, from the northeastern side, at the town center of Enfield. The southeastern end of the lake is fed by the Knox River. The lake's average depth is {{convert|30|ft}} with a maximum depth of {{convert|68|ft}}.<ref name=NHFG>{{Cite web| url=http://www.wildlife.state.nh.us/maps/bathymetry/mascoma_enfield.pdf| title=Mascoma Lake, Enfield, Lebanon| publisher=NH Fish & Game| access-date=September 2, 2014}}</ref>
The lake freezes during winter and is stable enough to be walked upon. Ice fishing is popular on the lake. The lake is stocked with trout by the New Hampshire Fish and Game Department.
Mascoma Lake often has a spring cyanobacteria bloom. Recent studies suggest that significant exposure to high levels of cyanobacteria producing toxins such as BMAA can cause amyotrophic lateral sclerosis (ALS). People living within half a mile of cyanobacterially contaminated lakes have had a 2.3 times greater risk of developing ALS than the rest of the population; people around Lake Mascoma had an up to 25 times greater risk of ALS than the expected incidence.<ref>{{cite journal |vauthors=Caller TA, Doolin JW, Haney JF, Murby AJ, West KG, Farrar HE, Ball A, Harris BT, Stommel EW |s2cid=35250897 |title=A cluster of amyotrophic lateral sclerosis in New Hampshire: a possible role for toxic cyanobacteria blooms |journal=Amyotrophic Lateral Sclerosis |volume=10 |issue=Suppl 2 |pages=101–08 |year=2009 |pmid=19929741 |doi=10.3109/17482960903278485 }}</ref>
In June 2009 the State of New Hampshire discouraged people from recreation in some areas of the lake because of the bloom.<ref>[http://des.nh.gov/media/pr/2009/090611enfield.htm State Issues Cyanobacteria Warning for Mascoma Lake]</ref> Aside from the bloom, the lake is generally considered safe for swimming,{{cn|date=July 2022}} and the town of Enfield maintains a public beach with a lifeguard on the lake.
NASA and its partners have used the frozen lake to test a robotic rover as a simulation of Antarctica.<ref>{{Cite web|url=http://www.cmu.edu/cmnews/extra/050309_lorax.html|title = Researchers Deploy Robot on Frozen Lake in Preparation for Antarctic Expedition}}</ref>
Mascoma Lake is home to the Dartmouth College sailing team. A community sailing club called the Mascoma Sailing Club<ref>[https://sites.google.com/site/shakersailclub Mascoma Sailing Club]</ref> also uses the lake.
==See also== {{portal|New Hampshire}} * Mount Assurance * Enfield Shaker Museum * List of lakes in New Hampshire
==References== {{reflist}}
{{Connecticut River}}
Category:Lakes of Grafton County, New Hampshire Category:New Hampshire placenames of Native American origin