McHenry County, IL Environmental Rules: Boat Dock Permits (2026)

030(A) creates General Permit Number 1 for routine, small-footprint work in flood hazard areas, and subsection (A)(3)(i) sets the rules for minor non-commercial boat docks. A dock cannot project more than 50 feet into a waterway, and never more than one-quarter of the waterway's width. Width is capped at 10 feet. On an L-shaped or T-shaped dock, the leg running parallel to the shoreline cannot exceed 50% of the owner's shoreline frontage or 50 feet, whichever is smaller. Docks must be aligned so they do not cross the straight-line extension of a neighboring property line into the water, and must stay at least 10 feet from that line.

Attached shore stations and boat lifts follow the same alignment rule. The general permit covers the dock structure itself only: no accessory roofs or elevated decks are authorized under it. To use General Permit Number 1, the owner (or someone with written owner authorization) files a stormwater management permit application with the Enforcement Officer before construction starts, describing the project, attaching any required federal, state or local approvals, and paying the permit fee. If the project does not fit the general permit's terms, the Enforcement Officer directs the applicant to apply for an individual stormwater management permit instead, which carries its own review.