How (and How Not) to Anchor in Current
June 03, 2019
Fast or slow, deep or shallow, just what are the do's and don'ts of anchoring in current?
As a Midwesterner, I’d spent countless hours on Lake Erie. On the Ohio. The Mississippi.
But nothing prepared me for Washington’s Columbia River. Nothing.
My wife Julie and I were guests of veteran river guide Ed Iman. The target: oversized sturgeon, those prehistoric monsters measuring up to 10 feet in length and weighing more than 300 pounds. At daybreak, the three of us left the launch and headed upriver. There, below the concrete behemoth that is Bonneville Dam, the Columbia is impressive. Massive. Frightening.
Motoring upstream of his mark, Iman told me to drop the anchor, a double-fluke hunk of metal that looked capable of securing the USS Ronald Reagan to the bottom. Slowly, we back-drifted downstream under power, paying out line – 350 feet in all.
“Throw the ball,” our captain said, and I did.
We were set. The anchor held our guide’s 24-foot Lund Baron tight over 60 feet of turbulent water that drops back into an 80-foot hole where, we were told, sturgeon lurk.
“One last thing,” Iman said to us. “See that knife on the console?”
We nodded to let him know we saw the knife.
“If this boat starts to turn, one of you cut the anchor rope. Do it quick. If we swap ends, we’ll go down immediately.”
We were silent, unaware that the most sobering information was the best yet to come.
“There’s a boat just below us,” Iman continued. “That’s what happened to him. If you run over it, you can still see the boat and anchor line on your depth finder. They never found ’em.
“Welcome,” he said, as he turned to the first rod, “to the Columbia River.”
Not every anchoring scenario will be like this. At times, securing a skiff in a current is simple: drop the anchor, pay out line and tie off. There are times, however, when anchoring in current can prove a bit sketchy due to any number of variables like bottom structure or type, water depth and, most importantly, the velocity of the current.
But fast or slow, deep or shallow, just what are the Do’s and Don’ts of anchoring in current? Here are three of the most commonly made mistakes when it comes to anchoring and advice on how not to make them.
THE WRONG ANCHOR
A 3-pound coffee can filled with concrete is not going to anchor your 18-foot sled well at all. Many recommend a Danforth style anchor for most applications. How big? Fortunately, most manufacturers include a size recommendation chart with their anchors. If you don’t know, ask questions. Lots of questions.
Scope is the ratio of anchor rode (rope) to water depth measured from the deck. Proper scope allows the anchor to set, or bite, into the bottom securely while allowing adequate lead for both vertical (critical in tidal situations) as well as horizontal movement. No universal answer exists for determining proper scope. However, experts claim a 6:1 or 7:1 rode-length-to-depth ratio is typical. Translation: 50 feet of water means letting out 300 to 350 feet of anchor rope.
NOT SETTING THE ANCHOR
The anchor must set to perform properly, and this means using the proper anchor as well as the correct scope. In current, it’s important to first motor well upstream of your intended final location. Then, using sufficient power to hold the vessel almost, if not entirely, stationary; then drop anchor. Shift to neutral, use a controlled drift down current powering up when necessary; apply proper scope, secure the rode to the bow cleat and allow the anchor to set.