The LaHave River mooring guide
The mooring field located at LRYC is a managed field, whereby the Rear Commodore manages the location of the moorings but the mooring and tackle is the personal property of the owner. New installations / movements /sales of any mooring in the field, can be achieved by first advising the Rear Commodore, who will ensure the club’s records are updated to reflect the changes.
The following information is meant as a GUIDE only to members.. A fixed mooring relies on three design criteria to hold your vessel in place during storm force winds and high waves; a block(normally concrete), suction to hold the block in the river bottom mud and shock strain relief. Unlike temporary anchors, the scope for a permanent mooring should be sufficient to allow for shock absorption, but not too long to interfere with other moorings. The size of the components are chosen to account for wear and shock strain, more than raw strength. The bottom chain weight provides shock relief when the vessel is pounding in high surf during storm wave action and the boat weather vaning. Some skippers may also use a shock relief system in the pendant.
The most common mooring practice at LRYC is to place one or two concrete mooring blocks, with an embedded steel loop or through hole for the ground chain. Larger vessels should consult with the Rear Commodore regarding block size. Good quality galvanized hardware and chain is recommended. Stainless steel corrodes quickly in low oxygen bottom mud. The ground chain is shackled to the mooring block and to the downline at the other end. A swivel is inserted at the intersection of the downline and the ground chain. The goal is to keep the hardware in the oxygen deprived bottom mud, which greatly reduces corrosion. The downline should be a bit longer than high tide depth to avoid lifting the ground chain when the boat is not on the mooring. A smaller second concrete block may also be chained 10 ft or less from the large block. The ground chain then continues from the smaller block. This system provides even more shock relief when the smaller block is lifted during storm force winds and waves.
To aid divers in recovery of missing moorings, consider attaching a buoy to the block that would float about three feet off the bottom, or even some lengths of floating line at intervals on the chain to assist in finding the tackle when it's covered in mud. It's quite deep in places in our field and some blocks and chain sink well out of sight even when you are right above them
If the existing tackle is too long, the best method is to shorten the ground chain. Simply move the downline shackle from the end along the ground chain towards the mooring block. The extra chain can be shackled back along the ground chain to add additional shock lifting weight. When maintenance is required the other components can be adjusted and the overall length and scope maintained.
Expect a large amount of marine growth on the first few feet of your mooring tackle. Some skippers find a coat of leftover bottom paint on these surfaces greatly reduces the mass of growth.
It is common practice to leave the pendant attached to the mooring ball.
Nylon pendants will sink, whereas polysteel line will float. A double pendant is called a bridle. It is recommended that the second pendant be spliced in a foot or so from the buoy. This method avoids twisting and chafing of the line near the thimble, a common failure point. Pendants should be sized to fit through the bow chocks. Pendants should be marked with a small buoy, or a few in-line net buoys, to mark the bitter end for passing boaters.
Both summer and winter mooring balls/markers should be labelled in a manner so the owner and/or boat can be identified. The size of the summer ball is determined by the weight of the downline, a much larger ball is required for the extra weight of a chain downline.
During the winter freeze-up, the local practice is to remove the tackle from the end of the ground chain and replace it with a ½” or larger polysteel line attached to a wooden marker (treated 4”x4”x16”) or smaller hard plastic ball. The winter stick downline is sized so that the stick is submerged at high tide and above the surface at low tide. The winter stick should not be so large as to cause lifting of the ground chain.
LRYC mooring field has a range of depth of approximately 6ft between low/high tides. Depths range from 5’ to 23” in the field. For approximate lengths of tackle, please contact the Rear Commodore. Consulting fellow long time members can also be beneficial.
Depth at your assigned mooring grid location is 8ft (low tide)
High tide: 8 + 6 (tide range) = 14ft high tide.
Ground chain: 14 * 1 ½ = 21 ft. (1 ½ to 2 times recommended)
Down line: 14 + 1 = 15ft. Add line for splices and loops
Pendant: Freeboard for the boat 4ft * 1¾ = 7ft pendant. (Add line for distance from where the pendant or bridle crosses the bow to the cleat (1ft for this example), splices and loops)
Recommended chain, shackles and downline size
(Only vessels to 30ft listed)
Ground Chain ⅝” (16mm) or larger. Boats less that 20ft, ½” (12mm)
Shackles to fit ground chain and thimbles
Downline ¾” (19mm) to 1” (25mm) polysteel or nylon 1” with galvanized thimbles
Down chain ⅜” inch galvanized schedule-40 or better
Pendant or Bridle ½” to ¾ polysteel, or ⅜” to ⅝” Nylon with white net buoys and thimbles
Suggested concrete mooring block dry weight:
10 - 17 500 lbs.
18 - 26 800 lbs.
27 - 35 2500 lbs.
36 - 45 2500 lbs.
45 - 55 3000 lbs.
Diagrams next page...
Three alternatives shown for buoy attachment.
- Mooring field and Tackle Guide