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    Estimating height of eye
    From: Bruce J. Pennino
    Date: 2013 Apr 6, 12:36 -0700

    Hello:

    I know this has been discussed before, but my goal is to mention a couple of procedures that can confirm estimates or improve guesstimates.

    Very steep slopes of carefully place rip rap are never steeper than 45*degrees.
    Also, a natural stone/gravelly slope that you can barely scramble up is probably
    1 vertical on 2 horizontal. Common steep engineered slopes are 1V:3H, because it is normally safe for a variety of soils. With this information and a cloth tape you can measure the length of slope and do a little math to help estimate.

    Try to stand on bottom and look up. Then use increments of body height. Or, buy a low cost inclinometer or device a forester uses. There are different types. I had one once that had an adjustable protractor attached to it. This gave angles very usable for crude survey. Some of these methods require a helper for reasonable results. I've used a metal 25 ft carpenter's tape. If it is not too windy, you can extend it above your head to improve estimates.

    One of my favorite procedures for accurate results is to find a spot where I can use a tape to measure vertically down to the water level (even sometimes a small angle). I measure from the water to the top of a pile or wall, and then get increments of height from there. I have a bunch of tapes that range in cost from $10 to $150. The latter is a calibrated 100.00 ft tape that seldom leaves the house unless I'm checking something(or calibrating something). The cheap cloth tape is ideal to use from a dock. the carpenter's belt tape can also work here.

    But after writing all this, except dropping a tape to the water level, these will only provide refined estimates.

    Good luck.

    Bruce
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