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Brian Elfert
06-18-2009, 12:06 PM
I need to determine some elevations in my yard to bury a drain pipe.

Any cheap/easy ways to do this? I tried a handheld GPS unit and the elevations were all over the place. I would move the unit a foot and the elevation would change 25 or 50 feet.

Jim O'Dell
06-18-2009, 12:10 PM
Do you need to know actual elevations, or just to get a consistent drop? If it the latter, a simple water level would work, then measure down the amount you want the drop to be over the distance you are measuring with the hose. Just get a length of clear hose the length you want to use, something to cap off the ends, and some water and food coloring for easy viability. Jim.

Scott Loven
06-18-2009, 12:18 PM
I would use a couple of wood stakes and a string. What kind of distance are you talking about?

Scott

Brian Elfert
06-18-2009, 12:59 PM
I would use a couple of wood stakes and a string. What kind of distance are you talking about?


I need to determine this over something like 175 feet. It is very difficult to tell because of the terrain if there is sufficient drop for a pipe to drain at the end.

I'll see if I can find my string and string level. My biggest concern will probably be getting the string tight enough to make it work.

John Keeton
06-18-2009, 1:41 PM
Brian, this isn't exactly to engineering standards, but should work for what you are doing. I have put a stake in the ground, with a cross member screwed to it with one screw so it was moveable, but with resistance. It needs to be oriented, or pointed, at the direction in which you want to measure the elevation. Put my 4' level on top of it, level it, and sight across the top of it at an upright that a friend holds for you. Cheap builder's level.

Steve Rozmiarek
06-18-2009, 1:56 PM
Brain, the tool for the job is a transit. Couple hundred will get you one, or I bet they can be rented.

A handheld gps device is practically usless for elevation. The recievers in those things are made for +/- meter accurate horizontal measurments. It costs a lot more, and requires a correction signal, RTK usually, to get accurate vertical measurments. Those systems are in the $30,000 and up price range.

Jeffrey Makiel
06-18-2009, 2:07 PM
I agree with Steve on the transit.

I'm not sure what you mean by a 'drain line'. Is it a buried rainwater pipe, or a sanitary sewer pipe (e.g., a poop pipe)?

If it's just a rainwater pipe, some mason's line and a $3.00 line level would suffice: Measure the length of the pipe run, determine its total drop (e.g., 1/4" per linear foot x total length), pull the line tight and level, and measure the drop between the line and pipe at the end of the pipe run.

Note: Always place the line level in the middle of the string so its weight does not skew the reading.

-Jeff :)

Gene Howe
06-18-2009, 2:14 PM
We used John's method to locate our sewer line from the house to the septic tank. Once we determined the feasibility and dug the trench, it was a simple matter to establish the 1/4" per foot drop that the code required.

Andy Haney
06-18-2009, 8:13 PM
What has been said about measuring methods is great.

FWIW...If you have options, a "stormwater" drain should fall at 1% grade (21" for your length) or more...but any fall will work if you can't get that much. Too flat and water could stand in the pipe, freeze in winter, etc.

Andy

Dick Strauss
06-18-2009, 9:16 PM
Brian,
You can always go really old school with a water level using a long piece of tubing. A roll of tubing will be pretty cheap and a water level is pretty accurate!

glenn bradley
06-18-2009, 9:37 PM
+1 water level. Cheap and easy and you can use the tubing for something else someday.

Mark Norman
06-18-2009, 11:24 PM
You can use a garden hose with a few feet of clear tubing on either end...save a few bucks over 100' of clear tubing. +1 on a water level, gravity dont lie;)

Larry Edgerton
06-19-2009, 6:57 AM
I use a water level on +$1M homes. I have had guys with lazers try to show I am inaccurate, but I never am. In fact it has been the other way around a couple of times. Make one up with a large resevoir, it will add to the accuracy if a drop or two is spilled. I use 4" pipe about two foot long.

Add just one drop of dish soap to get rid of the surface tension on the water, and add food coloring to aid sight line visibility.

Jeffrey Makiel
06-19-2009, 7:01 AM
I bought one of those electronic water level thingys. It works well especially if you are a one man show. Inexpensive too.

You mount the sensor box at one end of the pipe, and move the other end of the tube up/down until you hear the electronic buzzer.

-Jeff :)

Brian Brown
06-19-2009, 11:17 AM
Water Level.... Why make life hard?

Cliff Rohrabacher
06-19-2009, 4:46 PM
Garden hose with clear plastic vinyl tubing attached to the ends.
Get a couple stakes in the ground so you have them eyeball level to each other at the far ends of your drain line (start and end). Ya want 'em in well enough so a little bump here or there won't matter.

Attach the clear vinyl tubing to the stakes

Put water in the hose till the tubes each show enough water that you can see the water line..

Let it settle. Mark that on your stakes.

Those marks are dead level with each other.

You can do the trig to get your drain slope.

Jim Becker
06-20-2009, 5:28 PM
Brain, the tool for the job is a transit. Couple hundred will get you one, or I bet they can be rented.

Exactly what I was going to suggest. Relatively easy to use, too, once you do it once or see it done.

Brian Elfert
06-21-2009, 9:28 PM
I ended up using a string level which is plenty accurate for what I am doing. No need for a transit for this.

The bad news is that even though there is a steep drop at the end of my property the ground actually slopes up even with the drop accounted for! I was planning to install a drain line for a sump pump, but I can't if there is no drop in the line for the water to drain out.

Unfortunately I have no plan B so I need to go back to the city to get their blessing on a new plan once I come up with one.

Mark Norman
06-21-2009, 10:00 PM
Maybee a standpipe would be a solution for you in this case Brian. You can get away from the slope requirement an lay the pipe flat (local code permitting) by using a standpipe to create a head pressure on the pipe.

And just for clarification a transit is not the same as a level.

Brian Elfert
06-22-2009, 1:28 PM
Maybee a standpipe would be a solution for you in this case Brian. You can get away from the slope requirement an lay the pipe flat (local code permitting) by using a standpipe to create a head pressure on the pipe.

And just for clarification a transit is not the same as a level.

You're absolutely correct that a transit and level are two different things. In my case a simple string level worked well enough to figure out my elevations. I was able to measure down from the string once level to determine the elevation.

If I was pouring a foundation I would probably want to use a transit or laser level since a lot more accuracy is needed.