What are they recommending?
Have you ask them for lawyer referral?
fixing area were the sharp turn is. were drain tile goes through driveway area.
putting in min a settling pond. (larger main dam) nearest to the lake. will hold the most water. basically an overflow pipe on settling pond/s so water comes in and slows down and stuff sinks out to the bottom. tossing rock across the top of dams so if pipes plug, water goes over the top of them / spillway around the dams for settling ponds.
little iffy on the 2 smaller settling pond dams. perhaps rip rap between drain tile and were water level for settling pond would be. it is one of those things were until things start getting built, and everything gets stripped down, and see what the soil is like thing. and how much more erosion happens between now and then.
the opposite side of lake that the cabin is on. excavator work to strip out most of the trees to gain access to bank. to drop in rip rap. i am going to assume some dozer work to smooth it all out afterwards and then grass seed it and straw it all. to deal with erosion till grass grows in.
side of lake that the cabin is on. clear the brush leaving the trees if possible. and tossing in rip rap along the bank edge.
the issue with the rip rap rock, with all bids, is all companies want to clear it up first, and then only after clearing, give bid for rip rap rock itself. after all the clearing.
the area down below the dam, most likely running a drain tile from overflow pipe to marsh area, and ending the drain tile just past culvert. and toss a bunch of rock out at end of drain tile to reduce velocity of water and spread the water out. the marshy area is well a marsh and you will sink.
they are wanting to for most part doze the trees into piles and make mini piles and just set all the piles on fire as they doze stuff out.
the last company wants more in mid summer (dry months) for the work. to help deal with well mud and rain and just general overall weather. and rough estimate about 2 weeks worth of work. and did not want to deal with it at all during spring/fall at all. to much flowing water is my guess. and not wanting to jack around with a larger water trash pump if possible. so work can can happen more smoothly. also the hill sides are steep enough, that they are not wanting to slip and slide and fight any muddy wet hill sides.
of course portion of field "beans or corn" would be taken out so company has room to actually work and get things done correctly.
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other words to above, instead of an engineer specifically stating this and that down to the final inch and grade. just getting in there and getting it done, and working through issues as they show up.
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no lawyer referal