Lyon County, NV Environmental Rules: Erosion Control (2026)

A mass grading permit authorizes site grading for new or altered non-residential development before a building permit issues, under Lyon County Code section 15.240.01, and section 15.240.02 requires the permit before any site grading occurs on a project that has already received the required Community Development Department land-use approvals. The application, filed under section 15.240.04, must include a grading plan that identifies the limits of site disturbance, cut and fill quantities, on-site and off-site storm drain improvements, and 'the temporary and permanent erosion/sedimentation control measures per the approved Nevada Division of Environmental Protection Stormwater Pollution Prevention Plan (NDEP-SWPPP),' which may be submitted as its own separate plan.

Any application proposing to disturb more than one acre, or less than one acre but part of a larger common plan for development ultimately disturbing one acre or more, must include an approved Storm Water Pollution Prevention Plan (SWPPP) from the Nevada Division of Environmental Protection's Bureau of Water Pollution Control. Applications disturbing five acres or more must also include a Surface Area Disturbance permit from the Division's Bureau of Air Pollution Control. The reclamation plan portion of the application must separately address erosion and dust control needed to stabilize the site if development does not proceed, backed by a reclamation surety or cash bond covering one hundred fifty percent of the engineer's estimated reclamation cost, approved by the County Engineer before work begins.

Work exempt from a building permit under chapter 239, active-agriculture clearing and grubbing, and grading under fifty cubic yards do not need a mass grading permit at all under section 15.240.03.