The Upper Millstone River is a segment of the Millstone River that stretches from its headwaters in Millstone Township to where it meets the Stony Brook at Carnegie Lake in Princeton. This subwatershed includes areas of Cranbury, East and West Winsdsor, Plainsboro and Monroe. What happens to the land and water in this subwatershed affects hundreds of thousands of residents downstream as the Millstone makes its way to the Raritan River.
The Millstone River begins as a spring that percolates up in the coastal plain geology of East-Central New Jersey. In the days before development, this spring would flow through a network of miles of wetlands that would carry nutrients to native plants and wildlife. Today, these wetlands are fragmented by farms and industry.
The StreamWatch sampling site at its headwaters has been monitored by the Millstone Township Environmental Commission for 12 years. This site has shown consistently poor pH, phosphate and dissolved oxygen scores, affecting the water quality for miles downstream.
In addition to ongoing problems with water chemistry, the Upper Millstone has also suffered from significant increases in fecal contamination that correspond to the recent increases in rainfall we have seen statewide. As heavy stormwater runoff sweeps across lawns and developed areas, it collects waste contaminants, chemical fertilizers, and other pollutants on the way to our streams.
StreamWatch volunteer Ted Chase has been collecting bacterial samples at the Millstone River near Carnegie Lake in Plainsboro for four years. In that time, levels of E. coli have increased dramatically. In 2018, a year of record rainfall, E. coli at Ted’s site exceeded the state standard for healthy streams 50% of the weeks it was measured.
The Watershed Institute continues to advocate for better stormwater management and advancements in agricultural practices to protect and restore water quality in the Upper Millstone subwatershed. You can support our initiatives for stormwater utilities and restoration projects in our region by volunteering or becoming a member.
Many thanks to StreamWatch volunteers Ted Chase, Karuna Lynne Elson, Ken and Jackie Johnson, Jessie Liang, Doug Lischick and the Millstone Twp. Environmental Commission, and Barbara Zajac for monitoring the Upper Millstone subwatershed. Generous funding for the StreamWatch program is provided by Janssen Pharmaceuticals Inc, and the New Jersey Water Supply Authority.