*scratches chin* 100 x 200 and in texas.
will never do a "non floating dock" ever again. no if's and's or but's.
at my mom's house. (shared lake with others), used to have a 3 foot wide, 8 foot dock, concrete with a wood top. lake water would fluctuate any were from 1 to 5 feet in depth. it was ugly bad. trying to jump off into the deep end of the water. and more so it was nearly impossible to get onto dock nearly all year round. due to water level just to low.
at the farm here, 1 bridge that expands portion of more of a triangle lake. when 2 feet difference in water level, you completely forgot ever thinking about trying to get into a boat or onto a raft. from bridge or vice vs. heck in winter when when lake is normally the lowest. you need a 6 to 8 foot ladder.
with all of above, you never able to actually set down on side and put your feet into the water as you set on the edge. when you do, it is spring time (this time of year), and water just to cold to dangle your feet into the water / go swimming.
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at my mom's house and the bridge here on farm there are many folks that have "pillars" any were from 3" to 4" aluminum pipe. and then holes drilled through the bottom. then large 1/2" to 3/4" threaded rod pushed through and double nutted on each side, around 4 to 8 threaded rods total over 2 to 3 feet on the bottom end of the pipe. and then hammered down into the mud. then standard deck is built on top of it all. the lake just ends up being aahhh... ya no one wants to walk out up to your knees in mud. in attempt to go swimming. and no one wants to risk slipping on some slimed up ladder.
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floating dock. many builds out there. make them say 12 feet wide, x 12 feet long. get yourself about 10 to 12 or so 55 gallon drums. put in about 7 to 10 gallons of water (cold climates put in some RV anti freeze or like), the little extra "fluid" weight helps stabilize the dock/raft, so raft itself is more stable when a couple folks stand directly on a corner, the opposite corner does not raise hardly much at all. the width and length also help stabilize the dock/raft.
the one 55 gallon raft here on farm. has 10 55 gallon drums, 8 feet x 12 feet, (one 8 foot side = a 4 foot 2x4 ladder that folds up/down, fold up to keep out of water when not in use and keeps it from getting slimmed up), other 8 foot side = 12v battery and 12v trolling motor spot. 8 folks on it maybe a couple more. i want say 2000 or so lbs over all on it for weight. and kept on going without having issues. with folks diving from it, to tossing leg over side and crawling up onto it from in the water. to fishing from it and trolling it around, to tossing a live basket on it, to hooking up other boats to it. to dealing with anchors. it keeps on going.
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if you are wanting more of a bridge. say 3 to 5 feet wide, that is also doable. floating bridge that is. either use posts / pillars sunk down. or fully float entire bridge. and every so often. come out like out riggers on a backhoe do. and toss a 55 gallon drum. on each side. to help keep bridge tipping over.
the dock used for getting onto above raft. is T shape. 14 feet i want to say from bank, and then out in the water, 2 55 gallon drums on each side of the T, and then 2 55 gallon drums right on the center end. 6 3" poles / pillars / aluminum pipe total. 4 around T, and then 2 up on bank. wide enough so when raft comes up, you have plenty of room to step off, and set stuff, or dealing with a bass boat / fishing boat. and keeps dock from wanting to flip over. it sticks out far enough to keep the drums in winter even when lake get down to its lowest throughout the year. along with sticking out far enough so if you do go swimming you never need to walk through mud/weeds/moss to get back up on shore (women, kids, wimps, me) the drums on the dock also have 7 to 10 gallons of fluid in them (cold climate folks put in some RV antifreeze or like) and really help stabilize up the dock as well.
dock nor raft never come out. they are in year around and never removed. from negative digits in the in winter, to 110 plus degree summer the stay out in the water.
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*rubs chin*
i could see if you were on the ocean it self. and dealing with waves, i might bite
if you were wanting a "bridge" to physical drive something across, i might bite.
if you had some person that was using it as some sort of diving / jumping platform and was really into diving. i might bite.
but your on a 100 x 200 pond. were water level most likely varies throughout the year. by a few feet.
if you are set that much on non floating dock/bridge. see about finding a cheap trailer. cut the springs/axles off. along with tongue. make it is a deck over trailer. and the lumber on top is what holds the beams parallel to each other. maybe a cross brace were things connect. (end at bank, and further out were angle bracing or cantilever cables or like connect)
with above. get yourself a floating dock / raft. i would imagine yourself and family friends will like much better. being that much closer to water. vs being chased up a tree, and not being able to actually touch the water.
