Some boaters don't take a tidal river serious. We were anchored out in Essex yesterday having some lunch. Next thing we know a 68' Azimut pulls up on our front port side and drops anchor. Three people on the boat plus the Captain. Then a lady on the boat jumps in the water. The Captain throws her a life jacket to float on and to swim around. What they obviously didn't realize was that the tide was going out and the current was ripping. She tried to swim against the current and was going backwards. Then the guy on the boat jumps in without a jacket and makes his way to her. I yelled out to see if they were in trouble and he answered yes. My wife and I immediately tied a fender to a line and then tied line after line to each other to try to reach them as they were going down river. He was having trouble staying above water and out of energy. After getting out about 150' of line he grabbed he fender. My wife also tossed the floating cushion which reached him as well. She made a great toss in very windy conditions. Someone in a dingy pulled them onboard and they brought back my fender and cushion. They said thanks and motored away quickly on that beautiful boat. Just glad to know that they made it out ok and we all felt good that we may have saved someone from what could have been a tragic day. People should not ignore the strength of a river, especially a tidal river with an out going tide.