Mooring Buoy Inspection & Repair
When was the last time that you had your mooring buoy system inspected?
Experts recommend an inspection every three years in fresh water.
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Sleep better knowing that your mooring system is up to the task. It's important to know that the components of your mooring system are in good shape and properly sized for the environmental conditions and the length of your boat. |
Thankfully, corrosion (rust) of steel mooring chain is a very slow process in fresh water and it can takes decades before it weakens the chain links to the point where replacement is required.
However, the constant motion caused by wind and waves create friction where the chain rubs against itself or something hard like the anchor weight. Excessive chain wear combined with the mechanical forces caused by the chain kinking when it wraps around the anchor holding the mooring system in place, can cause the chain to break and is a leading cause of mooring system failure.
Fact: Although commonly used, large concrete blocks are not the best solution as anchors for mooring systems as the bottom chain (called a "rode") tends to wrap up around the block on the lake bottom, kinking the chain and shortening the rode, resulting in eventual damage to the chain and diminished holding capacity of the mooring system.
Fact: Keep in mind that concrete weighs approximately 60 % of its surface weight underwater... so a thousand pound block of concrete actually only weighs around 600 pounds on the lake bottom.
Fact: Most existing mooring buoy systems are not built or installed in compliance of Transport Canada's standards. Will your boat insurance cover boat damage or loss if your mooring fails?
Fact: Transport Canada (Canadian Coast Guard) have started a program of inspecting mooring buoy systems in British Columbia and are ticketing systems not in compliance.
Our professional team will inspect and video your existing mooring system from the anchor to the float. You will get a confidential, written report as well as a video of what we find.
Call or text Bart today for a "no obligation" quote: 250-254-5076 or email kootenaydiving@protonmail.com
Call or text Bart today for a "no obligation" quote: 250-254-5076 or email kootenaydiving@protonmail.com
Mooring Buoy Installation
Our heavy lift barge can accurately place mooring anchors - seen here recovering pumps
A mooring buoy system should be sized for the largest vessel that will be attached to it.
Mooring system design has been around for centuries... and yes...there is a correct way to do it.
Mooring anchor
Let's start with the correct anchor. Although heavy concrete blocks tend to be the "go to" anchor weight currently in use today, they really aren't well suited for the job.
Why a concrete block is a poor choice for a mooring buoy anchor.
As the wind blows the moored boat around the anchor, (called the "swing"), the rode starts wrapping up around the concrete block. As the bottom chain wraps around the concrete block it gets shorter and the pull from the moored boat becomes more vertical which reduces the desired buffering effect and greatly decreases the holding power of the mooring system. As well, a wrapped chain greatly reduces the life of the chain due to wear from friction and kinking.
Keep in mind that the results of chain wrapping around a mooring anchor is the primary cause of failure in a mooring system. The other causes are the improper sizing of the parts of the mooring system and using parts that are not suited for a mooring system.
What is a good choice for a mooring buoy anchor?
Research has shown that a mooring system anchor called a Dor-Mor is far superior in holding power - for it's weight - than any other weighted anchor. www.dor-mor.com The Dor-Mor design is basically an inverted pyramid that will settle into the soft lake bottom and provide up to ten times it's weight in holding power. In the unlikely event that it does pull loose, the design catches on the lake bottom and re-sets itself. Until the inverted pyramid settles into the lake bottom, the chain will slide up and over the sloped sides of the anchor instead of wrapping around it.
We have partnered with EnviroMarine Ltd - a local Canadian company - who custom manufacture inverted pyramid anchors utilizing a welded steel shell and reinforced concrete core.
The "Rode" - Bottom Chain
Attached to the mooring anchor weight is a heavy chain (called a "rode") that is optimally one and a half to three times as long as the water is deep. So for a mooring in 9 metres (30 feet) of water depth, the rode should be 13.5 metres (45 feet) to 27.4 metres (90 feet long).
The heavy bottom chain that is the correct size and length, does two things.
- As the wind and waves push the vessel away from the mooring anchor weight, a portion of the bottom chain lifts in a gentle "catenary" curve which provides a gentle buffering effect on the moored vessel. If installed correctly, this will eliminate shock loading on your vessel's deck hardware.
- A properly sized bottom chain will insure that the pull on the anchor is lateral... across the lake bottom, which multiplies the holding power of the anchor.
The Riding Chain
The riding chain is usually about half the size of the bottom chain with a length to match the maximum depth of the the mooring site. It attaches with a swivel between the bottom chain and the surface buoy.
Mooring Buoy
The mooring buoy itself is designed (and sized) to float the weight of the lighter riding chain that attaches the buoy to the bottom chain. Coast Guard /Transport Canada have specific designs for mooring buoys used in Canadian waters. In the last couple of years, enforcement has been initiated at the coast and more recently, inland lakes, where non-compliant buoys have been ticketed.
Location
It is important to site your mooring system so the scope doesn't put your vessel in danger of going aground in low water or infringes on your neighbour's waterfront. As well, an underwater inspection is necessary to make sure that there is nothing on the lake bottom that will impede the free swing of the rode.
Getting a mooring system installed.
Although installing a mooring system may sound overwhelming, it really isn't. All it takes is a phone call to us at Kootenay Diving and we will provide you with a "no obligation" quote.
Call Bart at 250-254-5076 or email kootenaydiving@protonmail.com
Our multi-purpose lifting barge can hoist up to 2000 pounds and can be put in at most boat launches.