PORTSMOUTH, N.H. (AP) — Two bridges connecting New Hampshire and Maine are about to open for river traffic.

Daily scheduled openings start Tuesday at the Memorial Bridge and the Sarah Mildred Long Bridge over the Piscataqua River between Portsmouth, New Hampshire, and Kittery, Maine.

Upon request, the Memorial Bridge will open at 30-minute intervals on the hour and half-hour from 7 a.m. 7 p.m.

When requested, the Long Bridge will open at 30-minute intervals (15 minutes before and 15 minutes after the hour), also from 7 a.m. to 7 p.m.

These scheduled openings will continue through Oct. 31. Both bridges will continue to open "on call" for commercial vessels in excess of 100 gross tons.