Face it, everybody has to go sometime. If you have a large group, you need a way to resolve this problem. Especially if you are in the backcountry where there are no facilities available. You don't want everybody going in their own private spot. It will eventually start to stink and you could step into someone else's spot. You have to know how to build a latrine.
The problem is you cannot put a latrine anywhere. You have to take into consideration; streams and water source, tent area and wind direction. The first part of this page covers in a little more detail than the section about where to put a latrine covered in How to Set up a Campsite.
By water source, I am talking about where you get your water to drink and cook with. If there is a stream nearby, you are probably using that for water. If there is not a stream or visible water on the surface you may have dug a well. Where ever you get your water, you do not want to pollute your source.
Just like water on the surface of the ground. Ground water in the water table flows. It takes all kinds of equipment and chemicals to figure out which way the ground water flows and at what speed, but usually it goes downhill. Your latrine will not be in the water table but the fluids from the latrine will soak down to it.
While the soil the water table flows through acts like a filter, the longer the latrine is used, the further the contamination will spread. There are other factors involved in the spread range of contaminants such as the amount of fluids and the type of dirt acting as a filter.
After you fill in the latrine and leave, the latrine still functions as a contaminating source. You have to guestimate how large the latrine is going to be and the amount of use it will get. The larger and more use it will get the further from streams and wells it should be. While i'm not talking about a latrine big enough to handle a battalion of soldiers but the closest distance should be at least 100 feet from a water source.
Before you start looking for a place to conceal the latrine, you have to figure out which way the wind is blowing most of the time. In the illustration, you can see that a latrine should be downwind from all activity places. If you place it upwind, you won't be pleased about the odor.
Once you figure out the wind direction you can consider privacy.
You also want it easy to find. Put it close to a small trail. If needed, you can hang a handkerchief or bandanna to show people the trail or a place to look for it off the trail. There should be enough brush between the tent area and the latrine to totally conceal it.
If you are not going to put a seat over your latrine, you better put the latrine within arm's length of a small tree big enough to hold the heaviest person that will be using it.
Ok, you found the ideal place to put the latrine but what do you do now? Start Digging. For a family of 6 or 4 adults for a week, the hole should be about the size of a 10 gallon pail. Put the removed dirt in a pile, off to the side to be used to cover the latrine when you leave. For every 2 additional adults the hole should be about 5 gallons bigger. After the hole gets to about 2 feet in diameter it is suggested to start digging deeper to increase the size.
Bacteria in the ground are only found in the top 6 to 10 inches because of available oxygen. So a pile deeper in the ground will not decompose. However, it is better to have 1 deep pit than 50 shallow pits scattered all over the woods.
If you want you can place a shelter over the latrine for inclement weather. To build a seat first you need a platform to place the seat on. If you are out in the woods more than likely you will not have dimensional lumber available so you have to use logs. If you are a savvy woodsman you can split the logs to give you a smooth surface. The 3 inch diameter logs should be long enough to go beyond the hole by at least 1 1 / 2 feet on each side and placed about 6 inches to the side on the ground. Put 4 more logs lashed together in sets of 2 across the first logs. This will give you a base.
To build a seat you need 4 branches about 2 inches in diameter with forks at the tops of each. Put 2 inch diameter logs in the forks making two pair and lash together tightly. Use rope to make cross bracing to stabilize the uprights.
Using more 2 inch diameter logs, lash them in pairs of two over the uprights leaving about a 9 inch space between the sets. The top of the seat should resemble the base turned 90 degrees. Use more rope diagonally between the uprights to tie them together and stabilize them. Take more 2 inch diameter logs and cut them just a quarter to half inch longer than the space between the legs. Place on end on a leg beneath the cross brace and push the other end to match. This will spread the legs tightening the cross braces and lock the legs.
Adjust the pairs of logs on the base so the legs of the uprights sit in the valleys between them.
That should do it. If you are going to build a seat you can omit putting the latrine within arm's length of a tree but some may prefer one to assist in getting off and on with. If you ever go camping with a large group of people in the remote woods without facilities now you know to build a latrine.