Millstone River Has Flooded, Closes Blackwells Mills Causeway

FRANKLIN, NJ — The Blackwells Mills Causeway in Franklin Township has been closed Friday due to flooding, Somerset County Public Safety announced around 7:30 a.m.

This closure joins the Griggstown Causeway in Montgomery that closed on Thursday afternoon around 12:15 p.m. due to flooding.

Both closures are due to flooding on the Millstone River. At Blackwells Mills the river has risen into the 7-foot action flood stage measuring at 7.63 feet as of 9 a.m. The river is expected to continue to rise into the minor flood stage by Sunday at 9 a.m. projected to rise to 9.2 feet.

The Millstone River at Griggstown is currently at the minor flood stage measuring at 11.74 feet as of 9 a.m. Friday, which is just below the moderate flood stage mark at 12 feet.

A flood watch has been issued for Somerset County until 6 p.m. on Saturday by the National Weather Service.

Three types of flooding are expected as a result such as low-lying and poor drainage flooding; flash flooding; and flooding of larger streams and rivers.

Residents who live across the Passaic, Raritan, and Rancocas basins in New Jersey or the Neshaminy, Schuylkill, and Brandywine basins across Pennsylvania and Delaware should be on alert.

Here is a look at the upcoming forecast:

Friday: A slight chance of showers before 11 a.m., then a chance of showers after noon. Areas of fog before 10 a.m. Otherwise, cloudy, with a high near 64. East wind 8 to 11 mph, with gusts as high as 24 mph. Chance of precipitation is 30 percent. New precipitation amounts of less than a tenth of an inch possible.

Friday Night: Showers, mainly after 8 p.m. The rain could be heavy at times. Patchy fog. Low around 54. East wind 9 to 13 mph. Chance of precipitation is 80 percent. New precipitation amounts between a quarter and half of an inch possible.

Saturday: Showers and possibly a thunderstorm. Some of the storms could produce heavy rain. High near 66. East wind 7 to 9 mph. Chance of precipitation is 90 percent. New rainfall amounts between a quarter and half of an inch possible.

Saturday Night: A chance of showers and thunderstorms. Cloudy, with a low around 62. South wind 5 to 7 mph. Chance of precipitation is 50 percent. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Sunday: A chance of showers and thunderstorms. Mostly cloudy, with a high near 80. West wind around 9 mph. Chance of precipitation is 40 percent. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Sunday Night: A slight chance of showers. Areas of fog after 2 a.m. Otherwise, mostly cloudy, with a low around 61. Chance of precipitation is 20 percent.

(Image via Shutterstock)

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