The Still River is a tributary to the Housatonic River in western Connecticut. Course and watershed The Still River headwaters emanate from Farrington's Pond () at the New York border with Danbury, Connecticut. It meanders through Sanfords Pond () and Lake Kenosia () before entering a concrete aqueduct near downtown Danbury. It then turns north, becoming a more conventional river as it cuts through Brookfield and southern New Milford before joining with the Housatonic (). The river has a drainage area of 85 square miles, and a mean flow of 377 cubic feet per second. The Still River has a brief but impactful history that has influenced its condition today. The farming industry in Danbury led to extreme pollution in the river. Beginning around the 1860s, the river again experienced significant mercury pollution from the hatting industry that continued for several years. This pollution had both ecological and anthropogenic effects on the surrounding environment, eventually leading to a need for remediation and cleanup. History Even before the hatting industry began in the late 1700s, the Still River was known as a dead river. This was due to pollution from farms in the area surrounding Danbury, CT. Farmers used the river as a site to get rid of waste and other toxic debris. Historical documents from Danbury and surrounding towns cited the river as a sewage dump around the 1880s, and the water was unusable for both agricultural and industrial use. It wasn't until a court case ruling in 1895, along with the Clean Water Act in 1972 that the city of Danbury was required to take responsibility for the state of the river. In 1993, Danbury constructed a new sewage treatment plant to help improve water quality. In 2014, the Still River Partners was created with the hopes of rebuilding the watershed, and as of 2019, this group is still responsible for maintaining and improving the river. Pollution Mercury nitrate was discharged to the river by the hatting industry from circa 1860 through the first half of the 1900s. The hat factories used the chemical in the felt making process to remove animal fur from pelts. During this time, levels of mercury were found to be 5-10 ppm with extremes up to 100 ppm. These levels were about 500 times higher than background levels. Although the hatting industry was the main cause of mercury pollution, there were other industries that