On Wed, 9 Apr 2008 10:04:27 -0400, "Eisboch" wrote:

Wayne is much closer than I according to this:

Minimum deadweight mooring weight:

Vessel length:

10 - 17 1000 lbs.
18 - 26 1500 lbs.
27 - 35 3000 lbs.
36 - 45 4000 lbs.
45 - 55 5000 lbs.

Submerged Weight Calculations

Concrete = required weight /.55 (example 1000 lbs./.55 = 1818 lbs.)
Granite = required weight /.64

http://www.harbormasters.org/rockport/mooring.shtml

The rule of thumb that I quoted (10 lb/ft) is for steel mushroom
moorings. Since they have a higher density than rock or concrete, and
tend to dig in faster, you can get by with less weight.