The only place where you can dump your gray water on the ground is on BLM lands, but state laws may still prevent you from doing so.
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Can I Dump my Gray Water on the Ground? - Boondocker's Bible
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Boondocking 101: How to Manage Water and Waste – The Flying Hens
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Boondocking Essentials - Reset Your Journey
What Is Bookdocking? Legality, Safety, and Tips, from a Van Lifer
Can You Dump RV Gray Water On the Ground Legally?
Is It Legal To Dump RV Grey Water on the Ground? - Drivin' & Vibin
Where Can You Dump RV Waste While Boondocking?
