Free Resource — All 50 States Covered
Plain-language greywater permit rules, DIY installation guides, and local rebate programs — organized by state. No legal jargon. No paywalls.
Everything a homeowner needs to legally reuse household water — from permit lookup to installation.
Every U.S. state's greywater laws explained in plain language — permit thresholds, code citations, and what's allowed without permits.
Browse all statesStep-by-step instructions for laundry-to-landscape systems, branched drain networks, and mulch basin sizing — no plumber required for most setups.
Read the guidesEnter your household size, washer type, and soil conditions. Get exact mulch basin dimensions, daily water volume, and permit status for your state.
Use the calculatorMany water districts offer $200–$500 rebates for greywater installations. Find programs in your area and learn how to apply.
Find rebatesWill it smell? Can renters install a system? What plants can I water? We answer the questions homeowners actually ask.
See all FAQsDownload our free PDF summarizing permit requirements, gallon thresholds, and rebate availability for every state on one printable document.
Get the PDFThe states where homeowners most often ask about greywater legality — click yours for full permit details.
No state permit required under 400 gpd. Local rules vary — Austin and Houston have different requirements.
Full TX guideType 1 General Permit exempts systems under 400 gpd. Tax credit available for qualifying systems.
Full AZ guideLaundry-to-landscape systems require no permit if you follow CPC Chapter 15 guidelines.
Full CA guideColorado legalized greywater in 2013. Permits required via local health departments. Denver has a streamlined process.
Full CO guideThree-tier system: Tier 1 (L2L) has the simplest process. Check your county health department first.
Full WA guidePlumbing permit required. NSF/ANSI Standard 41 certification needed. Greywater must pair with approved grey water disposal.
Full OR guideUnder 250 gallons per day, no permit required. Must overflow into sewer/septic and avoid surface ponding.
Full NM guideFlorida DOH permits greywater with county approval. Rules vary significantly by county and proximity to water table.
Full FL guideEnter your household size, washer type, and soil conditions. The calculator tells you exactly how large your mulch basins should be, how much water you can save per year, and whether your system needs a permit in your state.
Open the Calculator →One page per state — permit required, gallon threshold, code citation, and rebate status. Print it, share it, use it when planning your system.
Download Free PDF →Step-by-step, jargon-free instructions for the most common residential greywater systems.
The most popular no-permit system. Redirect washing machine drain water to mulch basins in your yard. Takes a weekend to install with $50–$150 in materials.
Complete L2L guideUsing shower and bath water requires more planning — most states require permits. Learn what's involved and which states allow it with simple guidelines.
Shower greywater guideHow deep, how wide, how many. Sizing your mulch basins correctly prevents ponding and keeps your system code-compliant. Includes soil type adjustments.
Mulch basin guideNot all detergents are safe for plants. Learn what to avoid (sodium, boron, bleach) and which brands are proven greywater-friendly.
Soap compatibility guideMaterials, permits, labor (DIY vs. contractor), rebates, and actual water bill savings. Based on real installations across five states.
Cost breakdownLiving in an HOA doesn't necessarily block greywater. Know your rights — some states restrict HOAs from prohibiting water-saving measures.
HOA rules guideClick any state for the full permit guide. Color codes: no permit permit required varies locally restricted
Quick answers to the questions homeowners ask most.
Greywater is wastewater from washing machines, bathroom sinks, showers, and bathtubs. It does not include toilet water (called blackwater), water from kitchen sinks (considered too contaminated with food waste and pathogens in most states), or dishwasher drain water. The laundry-to-landscape (L2L) system — using only washing machine water — is the simplest and most widely permitted type in the U.S.
In many states, no permit is required for a basic laundry-to-landscape system as long as you follow state guidelines (no surface ponding, water stays on your property, buried under mulch, etc.). States with explicit no-permit thresholds include Texas and Arizona (under 400 gpd), New Mexico (under 250 gpd), and California (L2L systems that don't alter existing plumbing). Always check your state guide and verify with your local building department — county rules sometimes differ from state rules.
Not if installed correctly. The key is covering discharge points with at least 2–4 inches of mulch and ensuring the water soaks into the soil immediately rather than pooling. Laundry greywater has a faint soap smell when fresh but becomes odorless within hours underground. Using plant-compatible, low-sodium detergents also reduces any organic load. Systems that develop odors are usually undersized — the mulch basins can't absorb water fast enough.
You can water non-food parts of food plants (like fruit trees and grapevines) but should not use greywater on vegetables, herbs, or root crops that touch the soil — even if the water looks clean. Most state codes explicitly prohibit greywater on edible crops. The concern is pathogens from skin and laundry residues that could contaminate produce. Stick to ornamental landscaping, fruit trees, and shrubs. Grass is also a good target.
A household of four doing about 6–8 loads of laundry per week can redirect 1,000–1,500 gallons per month to landscape irrigation. At typical water rates ($5–$9 per 1,000 gallons), that's $60–$180 in annual savings — more in drought-area states with higher tiered pricing. Water districts in California and Arizona report average household savings of 30–50 gallons per day from L2L systems.