Pin the joints of the crossties (sleepers) with steel rod.......no way
is the water pressure going to overcome the sheer strength of a steel
pin. Even a 20 or 30 penny spike used as a pin on a half lap joint or
a through joint would be more than sufficient even for a higher outer
frame.....

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Put some color in your cheeks...garden naked!
"The original frugal ponder"
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