Dock Damage

Grant · 05-20-2004, 01:01 PM

the ice did a number on a bunch of the docks on our shore this winter -- more so than I've seen in many years. Apparently, there was a stiff wind out of the northwest shortly after the 'break-up' and that sent some large pieces drifting hard toward shore. I posted one shot of a neighbor's dock in the Photopost section. Those lift-outs are looking mighty smart these days!

Anyone else suffer considerable dock damage this year?

KPW · 05-20-2004, 01:51 PM

We suffered extensive damage to our sundeck on Cow. This seemed to occur during ice-in though.

jrc · 05-20-2004, 02:57 PM

The docks at out condo did pretty well, a few have a little slant to them. But at least five pilings where damaged. Two are totally uprooted and are floating free near the docks. At least three are pointing in directions other than straight up. It's amazing how selective the ice can be.

Frank · 05-20-2004, 04:53 PM

I was at my place in April, just before ice out, and our dock had buckled some as one of the supports had been knocked out by the ice during the winter... I hate to think what happened at ice out... I'll find out soon enough.

jimbob1603 · 05-21-2004, 08:25 AM

I've been led to believe that ice damage occurs in the spring (during ice out) when the ice has a tendacy to drag the dock, and when pressure ridges develop. So, it is only necessary to activate your circulators sometime in March.

I am considering leaving my dock & boatlift in the water next winter and letting nature take its course until early spring, when I'll turn on the circulator. I don't want to leave the circulator on all winter, it'll cost a fortune to run.

Any thoughts? Pros/Cons ....

Mee-n-Mac · 05-21-2004, 10:36 AM

Quote:

Originally Posted by jimbob1603

I've been led to believe that ice damage occurs in the spring (during ice out) when the ice has a tendacy to drag the dock, and when pressure ridges develop. So, it is only necessary to activate your circulators sometime in March.

I am considering leaving my dock & boatlift in the water next winter and letting nature take its course until early spring, when I'll turn on the circulator. I don't want to leave the circulator on all winter, it'll cost a fortune to run.

Any thoughts? Pros/Cons ....

I'm not sure I agree that the *only* time damage occurs is during the spring. I'd think pressure ridges and ice movement can happen during freeze up (and other times) as well. That aside, waiting until March is too late. I'm not sure how quickly the circulator would melt the ice around your dock if you let it freeze up good. Ours goes in late fall and then gets turned on later in the winter, only when the temps have dropped enough to start freezing. It runs on a timer so it's not always on (saves $$), just enough to prevent ice formation. I'll see if I can find out what the electric bill is.

Onshore · 05-21-2004, 10:53 AM

The ice damage that occurs in the spring is generally the result of wind blown ice sheets. A circulator won't save your dock if that's what is happening.

Frank · 05-21-2004, 11:19 AM

Quote:

Originally Posted by jimbob1603

I've been led to believe that ice damage occurs in the spring (during ice out) when the ice has a tendacy to drag the dock, and when pressure ridges develop. So, it is only necessary to activate your circulators sometime in March.

I am considering leaving my dock & boatlift in the water next winter and letting nature take its course until early spring, when I'll turn on the circulator. I don't want to leave the circulator on all winter, it'll cost a fortune to run.

Any thoughts? Pros/Cons ....

Without a circulator, long before ice out, the ice and changing lake level will have likely done major damage. This year, even with a circulator, my dock was damaged well before ice out.

As another poster says, the circulator is to protect the dock while the ice is in. During ice out, the circulator does nothing to protect the dock from ice sheets slamming into it. Some people have pilings in front of their docks to ward off the blows from ice sheets.

Frank

jimbob1603 · 05-21-2004, 02:44 PM

I guess general concensus feels that the circulator should be run whenever ice formation is probable; don't let ice form around the dock.

I'm not worried about damage from iceflows, I'm in a protected cove.

But, I am very worried about the cost of running a 1/2 horsepower motor for 12 hours a day for 5 months; sounds very expensive.

Frank · 05-21-2004, 04:36 PM

Quote:

Originally Posted by jimbob1603

I guess general concensus feels that the circulator should be run whenever ice formation is probable; don't let ice form around the dock.

I'm not worried about damage from iceflows, I'm in a protected cove.

But, I am very worried about the cost of running a 1/2 horsepower motor for 12 hours a day for 5 months; sounds very expensive.

Let's see... a 1/2 horsepower output motor running at 75% efficiency takes about 500 watts of input power. So, it takes 1 kilowatt hour of power to run for 2 hours, or 6 kWH for 1/2 a day. At 12 cents per kWH, that's 75 cents a day to run your motor, or around $100 total for the four or five months you need it.

Hopefully, I got those numbers right.

madrasahs · 05-21-2004, 09:33 PM

Quote:

Originally Posted by jimbob1603

I've been led to believe that ice damage occurs in the spring (during ice out) when the ice has a tendacy to drag the dock, and when pressure ridges develop. So, it is only necessary to activate your circulators sometime in March.
Any thoughts? Pros/Cons ....

Here, Winnipesaukee Aquatherm runs two circulators on timers set for the middle of the night -- when temps are coldest.

Ice-out these past two years had thick ice -- about 6-8' thick; however, it was very fragile. Winds blew the floes back and forth, but just shredded themselves against one another -- or against docks and pilings -- with no damage except to the edges of the floes themselves.

This winter, the only damage my dock received was slight and happened mid-winter -- not during ice-out. Last year, one of the circulators failed, and I had four pilings pushed out from under the dock. That also happened mid-winter -- not during ice-out.

Quote:

Originally Posted by Frank

Some people have pilings in front of their docks to ward off the blows from ice sheets.

Dock constructors call those "tie-off" pilings, installed so that you can secure your boat without having to use mooring whips.

There may be bays on Winnipesaukee where a mass of circulators keep the ice away from shore around its borders. The ice sheets could get some headway from a strong wind, then.

That doesn't happen in my immediate area -- there are large stretches of ice buttressed right against the shore.

jimbob1603 · 05-24-2004, 10:14 AM

500 watts sounds too good to be true in the real world. Now put that aquatherm in the water so that we see 1/2hp at the impeller. I bet it sucks down 2500 watts.

I'd love to put an amp meter on one of these puppies to see what they really draw while loaded. I bet rated vs reality are gonna be quite different.

In any case, I'll purchase one and try it out this winter. I'm desperate to not drag out the docks & boatlift this fall. If I can get by with a $200 electric bill, I'll consider it a bargain!!

madrasahs · 05-24-2004, 10:48 AM

Quote:

Originally Posted by jimbob1603

In any case, I'll purchase one and try it out this winter...If I can get by with a $200 electric bill, I'll consider it a bargain!!

I shut off my two circulators in the first week in April, and ran a $400 electric bill for this past winter. I'd say you got it right.

05-20-2004, 01:01 PM	#1
Grant Senior Member Join Date: Jul 2002 Location: Pennsyltuckey, Tuftonboro, Moultonborough Posts: 1,485 Thanks: 337 Thanked 212 Times in 116 Posts	Dock Damage the ice did a number on a bunch of the docks on our shore this winter -- more so than I've seen in many years. Apparently, there was a stiff wind out of the northwest shortly after the 'break-up' and that sent some large pieces drifting hard toward shore. I posted one shot of a neighbor's dock in the Photopost section. Those lift-outs are looking mighty smart these days! Anyone else suffer considerable dock damage this year?

05-20-2004, 01:51 PM	#2
KPW Senior Member Join Date: Apr 2004 Posts: 378 Thanks: 710 Thanked 116 Times in 58 Posts	Kpw We suffered extensive damage to our sundeck on Cow. This seemed to occur during ice-in though.

05-21-2004, 08:25 AM	#5
jimbob1603 Senior Member Join Date: May 2004 Posts: 71 Thanks: 0 Thanked 0 Times in 0 Posts	Ice Damage Question I've been led to believe that ice damage occurs in the spring (during ice out) when the ice has a tendacy to drag the dock, and when pressure ridges develop. So, it is only necessary to activate your circulators sometime in March. I am considering leaving my dock & boatlift in the water next winter and letting nature take its course until early spring, when I'll turn on the circulator. I don't want to leave the circulator on all winter, it'll cost a fortune to run. Any thoughts? Pros/Cons ....

05-21-2004, 02:44 PM	#9
jimbob1603 Senior Member Join Date: May 2004 Posts: 71 Thanks: 0 Thanked 0 Times in 0 Posts	So ..... I guess general concensus feels that the circulator should be run whenever ice formation is probable; don't let ice form around the dock. I'm not worried about damage from iceflows, I'm in a protected cove. But, I am very worried about the cost of running a 1/2 horsepower motor for 12 hours a day for 5 months; sounds very expensive.

05-24-2004, 10:14 AM	#12
jimbob1603 Senior Member Join Date: May 2004 Posts: 71 Thanks: 0 Thanked 0 Times in 0 Posts	Its gotta cost more than that .... 500 watts sounds too good to be true in the real world. Now put that aquatherm in the water so that we see 1/2hp at the impeller. I bet it sucks down 2500 watts. I'd love to put an amp meter on one of these puppies to see what they really draw while loaded. I bet rated vs reality are gonna be quite different. In any case, I'll purchase one and try it out this winter. I'm desperate to not drag out the docks & boatlift this fall. If I can get by with a $200 electric bill, I'll consider it a bargain!!

05-20-2004, 02:57 PM	#3
jrc Senior Member Join Date: Apr 2004 Location: NH Posts: 2,689 Thanks: 33 Thanked 439 Times in 249 Posts	The docks at out condo did pretty well, a few have a little slant to them. But at least five pilings where damaged. Two are totally uprooted and are floating free near the docks. At least three are pointing in directions other than straight up. It's amazing how selective the ice can be.

05-20-2004, 04:53 PM	#4
Frank Senior Member Join Date: Apr 2004 Posts: 54 Thanks: 0 Thanked 2 Times in 2 Posts	I was at my place in April, just before ice out, and our dock had buckled some as one of the supports had been knocked out by the ice during the winter... I hate to think what happened at ice out... I'll find out soon enough.

05-21-2004, 10:53 AM	#7
Onshore Senior Member Join Date: Apr 2004 Posts: 500 Thanks: 12 Thanked 400 Times in 143 Posts	The ice damage that occurs in the spring is generally the result of wind blown ice sheets. A circulator won't save your dock if that's what is happening.