Dreaming of a tiny house on the coast or a cabin in rural Delaware? Composting toilets are a smart solution for many off-grid, eco-friendly, or remote projects. But are composting toilets legal in Delaware—and what does the law really require? Let’s break down Delaware’s composting toilet laws, so you can make informed choices without risking a run-in with the inspector.
Are Composting Toilets Legal in Delaware?
Yes, composting toilets are legal in Delaware, but with a few key conditions. As with most states, Delaware law focuses on protecting public health and the environment, so not just any composting toilet setup will be approved. The type of system you install, where you install it, and how you handle both toilet and greywater are all important.
Who Regulates Composting Toilets in Delaware?
The Delaware Department of Natural Resources and Environmental Control (DNREC) regulates all onsite wastewater systems in the state—including septic, holding tanks, alternative systems, and composting toilets. Local building or health departments may add requirements, especially in incorporated towns or coastal areas.
What Does Delaware Law Require?
- Composting toilets must be approved systems: Delaware generally requires composting toilets to be NSF/ANSI Standard 41 certified (a national safety/performance benchmark). Homemade or untested systems are rarely approved.
- Permits are required: Any new construction, remodel, or change in use involving a composting toilet must be permitted by DNREC. This usually involves submitting plans, product documentation, and a site/soil evaluation.
- Greywater disposal is required: Even if you use a composting toilet, Delaware law requires that all greywater (from sinks, showers, and laundry) be disposed of using an approved system—usually a septic tank and leach field or an engineered greywater system. Composting toilets alone do not meet all sanitation requirements.
- No surface discharge: Greywater or compost leachate cannot be released to the ground surface or waterways. Safe containment and disposal are mandatory.
- Proper maintenance and no nuisances: Composting toilets must be installed and maintained to prevent odors, insect problems, or contamination of soil and water.
When Are Composting Toilets Allowed?
Composting toilets are most commonly approved for:
- Remote, off-grid, or seasonal properties where traditional septic is difficult or costly
- Tiny homes, cabins, yurts, or other nontraditional structures
- Areas with high groundwater, poor soils, or small lot sizes
In urban and suburban settings, approval is more challenging, and a compelling case must be made for a composting toilet.
Steps to Approval in Delaware
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Contact DNREC and your local officials:
- Ask about requirements, permitted products, and the process for your project location.
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Choose an approved composting toilet:
- Stick with an NSF/ANSI 41 certified model. Save documentation for your application.
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Submit a site and waste management plan:
- Include product details, how you’ll manage greywater, and soil/site evaluation results.
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Get your permit before installation:
- Install only after DNREC issues your permit. An inspection is often required once installed.
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Maintain your system:
- Keep up with all recommended maintenance, and never allow odors or contamination. Records may be needed for resale or future inspections.
What About Greywater?
Delaware law treats greywater (from sinks, showers, laundry) separately from toilet waste. Even with a composting toilet, you must have a permitted way to treat and dispose of all greywater. Most often, this is a septic tank and leach field or an engineered alternative system. Surface discharge or illegal dumping can bring fines and orders to remove your system.
Penalties for Non-Compliance
Skipping the permit process, installing an unapproved system, or mismanaging greywater can lead to stop-work orders, fines, and problems if you ever sell the property. Health and safety complaints may trigger DNREC inspections and enforcement.
Tips for Hassle-Free Composting Toilet Approval
- Start by talking to DNREC and your county or town—requirements can differ in coastal or municipal areas.
- Stick to certified systems and keep all documentation for permits and future property sales.
- Plan your greywater system at the same time as your composting toilet for the smoothest approval process.
- Maintain your system—odor or nuisance complaints are a common cause for code enforcement action.
Helpful Resources
- Delaware DNREC – Onsite Wastewater Systems
- NSF/ANSI 41 Composting Toilet Standard
- EPA: Composting Toilets Guidance
Final Thoughts: Composting Toilets in Delaware—Legal, but Don’t Skip the Permits
Delaware supports sustainable options like composting toilets, especially for rural and off-grid projects, but only if you follow the rules. Use a certified system, get permits, and address greywater from the start. With a little planning, you can enjoy eco-friendly living on your terms—without legal headaches.