Quick Answer
YES, rainwater harvesting is possible with an outhouse. It's a great way to supplement water for flushing and other uses, reducing reliance on external water sources and minimizing water waste.
Choosing the Right outhouse Design
When designing or selecting an outhouse for rainwater harvesting, consider a model with a built-in roof or a free-standing structure that can accommodate a roof collection system. The outhouse’s location should be sloped to allow water to flow away from the structure, ideally onto a separate collection area. Aim for a minimum roof surface area of 40-50 square feet to ensure adequate water collection.
Rainwater Collection and Storage
To store collected rainwater, use a separate tank or cistern with a capacity of at least 50-75 gallons. The tank should be positioned under the outhouse’s collection area, ideally with a slight slope to facilitate gravity-fed flow. Implement a first flush device to divert the initial flow of water, which may contain contaminants, and allow cleaner water to enter the storage tank. A roof catchment area with a surface area of 1 square foot per gallon of storage capacity is a good general guideline.
Water Treatment and Distribution
After collecting and storing rainwater, consider implementing a basic treatment system to ensure the water is safe for flushing and other uses. This can include a sedimentation chamber, a filter, and perhaps a UV treatment unit. Install a pumping system to transfer the treated water to the outhouse, ensuring a stable flow rate and preventing back-siphonage.
Find more answers
Browse the full Q&A library by topic, or jump back to the topic this question belongs to.