River traffic. Piscataqua River currents restrict travel by tankers and other large vessels to slack tide, roughly four hours a day. See chart below for slack tide at the entrance to Portsmouth Harbor. The entrance is nearly three miles from the location of the PortsmouthNH.com's HarborCam. Slack tide at the Harbor Cam is roughly a half hour later. A schedule of shipping in the Piscataqua is not available.
Piscataqua River Currents|
Tue 12:33am -1.76 knots Max Ebb
Tue 02:45am Moonset
Tue 04:33am 0.00 knots Slack, Flood Begins
Tue 05:13am Sunrise
Tue 06:22am 1.04 knots Max Flood
Tue 09:54am -0.00 knots Slack, Ebb Begins
Tue 12:52pm -1.82 knots Max Ebb
Tue 04:10pm Moonrise
Tue 04:43pm 0.00 knots Slack, Flood Begins
Tue 06:49pm 1.37 knots Max Flood
Tue 08:05pm Sunset
Tue 10:36pm -0.00 knots Slack, Ebb Begins
Wed 01:26am -1.94 knots Max Ebb
Wed 03:18am Moonset
Wed 05:12am Sunrise
Wed 05:24am 0.00 knots Slack, Flood Begins
Wed 07:17am 1.16 knots Max Flood
Wed 10:51am -0.00 knots Slack, Ebb Begins
Wed 01:44pm -1.92 knots Max Ebb
Wed 05:21pm Moonrise
Wed 05:30pm 0.00 knots Slack, Flood Begins
Wed 07:41pm 1.53 knots Max Flood
Wed 08:06pm Sunset
Wed 11:25pm -0.00 knots Slack, Ebb Begins
New Hampshire-Maine border. The N.H.-Maine border lies in the middle of the Piscataqua River. Its exact location was the subject of a long-running dispute settled by the U.S. Supreme Court.
Piscataqua River. This Piscataqua River is a 13-mile long tidal estuary formed by merging of the Salmon and Cocheco rivers. The river, which separates Maine and New Hampshire, also drains Great Bay, a National Estuarine Research Reserve site. The last 8.8 miles of the Piscataqua River constitute Portsmouth Harbor, which stretches across New Castle, Portsmouth, and Newington, and the Maine communities of Kittery and Eliot.
Currents. The swift currents of the Piscataqua River make Portsmouth Harbor one of the fastest flowing commercial port waterways in the northeastern United States. The ice-free deep-water channel has been used for shipping since the 1600s.
What kind of name is Piscataqua (pis-cat-a-qua)? Easy for you to say, but not so easy to spell. See an extended examination of the origin of the word at SeacoastNH.com and 20 ways to spell Piscataqua.
More information. For more about the Piscataqua River, see the Army Corps of Engineers Water Resources web page.