Whether you are on a camping or hunting expedition or even at home and the utilities are disrupted the call of nature needs to be heeded. People tend not to plan properly for the disposal of human waste and this can cause problems after a few days. The problems can be serious ones, such as rodent and insect infestations, being exposed to diseases and the growth and spread of harmful bacteria, not to mention the possible contamination of your drinking water source.
Unless you are in a survival situation where you find yourself lost or stranded then you need a designated area. You simply cannot find the nearest tree or bush to slip behind. Waste must be contained and controlled regardless of where you are.
If you have the room in your yard and the space is far enough away from any surface water source or private well then anyone can build their own latrine (outhouse). As far as a specific distance from a water source, it depends on particular codes and laws in your area and if you live in an unincorporated area then common sense dictates as far away as possible. The waste in the pit will break down over time, leach into the soil, and as it makes its way through the soil it is filtered and scrubbed (sanitized) and will eventually make its way to underground springs and aquifers.
The containment pit must not be dug below the water table. If the latrine is for emergency use only when the power goes out because of a crisis then the depth of the pit can be as little as two feet deep and can be dug as needed and filled in once the crisis is over, or you can construct a structure around the pit for a permanent latrine.
For short-term emergency use, dig a trench three feet deep, two feet wide and four feet long. Screen with tarps and provide a source of light. Leave the excavated soil in a pile close by with a shovel and a bucket of lime for odor and bacteria control. After each use, sprinkle lime into the pit and cover with a few shovels full of dirt. If you have small children or pets, you should build a cover that fits over the trench and cutout holes, to prevent anyone from falling into the pit.
If the latrine will remain in place year around then the pit should be shored up to prevent erosion of the walls. You can shore up the walls with stone or bricks or use concrete by building a retainer wall and backfilling between the wall and the sides of the pit. The bottom of the pit must not be covered to allow the waste to leach away otherwise; the pit would fill up and have to be pumped on a regular basis. It generally takes about a year for the sized pit described (if full) to breakdown. Natural bacteria will go to work and break down all solid waste.
If on a camping trip in a remote area that is not a camping grounds then dig a small hole as needed and immediately cover up. If with a group, find a spot 50 to 75 feet from the main camp, mark the trail well, dig a small trench, and screen with vegetation or tarps and always cover any waste immediately.