A Guide to Finding the Ordinary High Water Mark - #6 - YouTube

In this video, we are going to talk about how to measure the Ordinary High Water Mark

on a property with no or few field indicators.

For this example, we are going to measure the OHWM here at a location where we have

field indicators, and then we are going to go to the beach that is behind me where there

are NO field indicators and we are going to transfer that OHWM measurement over to the

beach area.

So the first thing you need to do when you are going to measure the OHWM is to gather

some tools, and these should be tools that you probably have around your house somewhere.

One of the things you are going to need is a measuring tape.

Another thing you will need is some kind of level.

What I have here is a line level, but you can also use a level that you might have in

your garage.

The third thing that you are going to need is something straight and level and long enough

that it would extend from the shoreline out over the water's surface.

So there is a few different things that you could use.

You could use a broom handle, you could use a piece of wood that you might have, you could

use a level that you might have in your garage.

What I am going to use today for this purpose is a survey rod.

Next we want to talk about when to measure the OHWM.

You want to make your measurements on a calm day, when there isn't any wind that is creating

waves crashing on the shoreline.

A day like this where there is a little breeze and a little bit of water surface interference

is fine - you can still get a good measurement.

The next thing you want to watch for is boat wakes.

You want to make sure that you wait until the water calms down before you take your

measurements.

Lastly, you want to make sure that you take all of your measurements on the same day,

so that the water elevation is consistent.

Now that you have the proper tools to measure the OHWM, Iam going to walk you through the

steps of the measurement you need to take.

First you need to find a location on the lake where there is visible evidence of the OHWM.

This is a good location because you can see a definite difference between the lake bed

and where you have no vegetation, and the sandy slope where is comes up to an area where

you have vegetation growing, This is where you are going to find the OHWM and this is

a good place to measure it.

Make sure that you have permission to access the property that you are going to measure

the OHWM on.

So let's make our first measurement!

The first thing you want to do is take the survey rod and place it at the OHWM.

The next thing you want to do is take your line level and put it on top so that you can

hold the survey rod level.

Next, you want to measure down from the survey rod to the water's surface.

This measurement is approximately two tenths of a foot.

Once you have recorded this measurement, take several more measurements along the OHWM--along

the SAME shoreline--to see if you are being consistent.

If these measurements are consistent, it could be a good indication that you've correctly

identified the OHWM.

When you are confident that you know how much higher the OHWM is than the water's surface,

return to the property with few or no field indicators of the OHWM.

Now we've returned to the location where there are no or few indicators of the OHWM and we

need to find the location of the OHWMon this beach.

You will do this by using the measuring tape to measure up to two tenths of a foot from

the water's surface and then using the survey rod, you will go over to the shoreline two

tenths of a foot above the water's surface and find where the location of the OHWM.

So take your survey rod and put it somewhere along the shoreline that you think approximates

the OHWM.

Get the survey rod level and take a quick measurement to see how far above water's surface

you are.

Ok, we are a little bit too high at three tenths of a foot, so what I am going to do

is slide the survey rod down a little bit.

I am going to keep it level and I am going to remeasure.

That location is approximately two tenths of a foot above the water's surface.

Repeat this measurement at several other points along the beach.

Mark each location of the OHWM with a flag or a wooden stake or spray paint, so that

you can get a good visual representation of the location of the OHWM.

Now lets talk about how to record the location of the OHWM for a DEQ permit application.

If you are planning to submit an application to the DEQ for a construction project at or

near the shoreline, you may want to follow these next steps.Take photographs of the markings

or field indicators and record measurements of the location of the OHWM so that it can

be located in the future by others who may need to find the location you have identified,

such as DEQ or the construction contractor.

Photographs should show the location of the OHWM from several angles, including from off

shore if possible.

For example, take a photo from the dock or boat or by wading out into the water.

After you have taken a few photographs, you may also want to take a few measurements to

include with your permit application.

Measurements should be recorded from permanent, stationary objects like buildings, large trees,

fences, or property markers to the OHWM.

The location of the OHWM and the measurements you've just taken should be included in

your DEQ application on the site drawing.

Thanks for watching our video series, for more information go to our website at michigan.gov/deqinlandlakes.