Great Lakes: jurisdiction and open-water rules

Orientation only. Verify current rules with the USCG Great Lakes District and the relevant state agency before launching. See Waterway Rules hub for jurisdiction overview.

• The Great Lakes are international waters shared with Canada. The international boundary runs through the center of the lakes and connecting channels. The USCG has jurisdiction on the US side; Transport Canada and the Royal Canadian Mounted Police have authority on the Canadian side. Crossing the international boundary with a recreational vessel requires proper documentation and customs reporting procedures for both countries.
• US-Canada border crossing by boat requires reporting your arrival. US recreational boaters returning from Canadian waters must report to US Customs and Border Protection (CBP). The CBP ROAM app lets you report your arrival without requiring a physical stop at a border station, but you must report your return. Failure to report is a violation. Canadian boaters entering US waters must similarly report to CBP.
• USCG Great Lakes districts cover different lake areas. The USCG Great Lakes District (formerly the Ninth District) covers the Great Lakes region. USCG Stations are positioned at key ports and respond to emergencies on US waters of all five Great Lakes and the connecting channels (St. Marys River, Straits of Mackinac, St. Clair River, Lake St. Clair, Detroit River, Niagara River, St. Lawrence River to the international boundary).

• Great Lakes: shared international waters. USCG on US side; Transport Canada / RCMP on Canadian side. International boundary at channel centerlines.
• Border crossing (US-Canada): CBP ROAM app for reporting your arrival on return to US. Must report regardless of vessel size. Failure to report = violation.
• USCG Great Lakes District (formerly the Ninth): covers all five Great Lakes and connecting channels (St. Marys, Mackinac, St. Clair, Detroit, Niagara, St. Lawrence to the boundary).

• The Great Lakes fall under the Inland Navigation Rules, not the International COLREGs. The line between International and Inland Rules runs along specific demarcation lines at lake and river entrances. On the open Great Lakes, US Inland Rules govern. The practical difference for recreational boaters is small (the rules are nearly identical in most situations), but the Inland Rules include specific provisions for Great Lakes vessel traffic and commercial operations.
• Recreational boats with a VHF must monitor Channel 16 (or Channel 9) while underway. The USCG monitors Channel 16 continuously on the Great Lakes. Keep the radio on Ch 16 whenever you are not using it to talk. On the Great Lakes, commercial vessel traffic (lake freighters, tankers, and ferry traffic) uses VHF to broadcast their position and intentions on narrow channels. Monitoring Ch 16 (and Ch 9 for small craft calling) is not a formality on the Great Lakes; it is an active safety tool.
• Lights and shapes requirements apply at all hours of low visibility, not just at night. In fog, heavy rain, or reduced visibility conditions on open lake water, navigation lights must be displayed. Great Lakes fog banks can develop quickly. Radar reflectors are strongly recommended (required in some commercial traffic lanes) because Great Lakes commercial vessels are large and fast relative to recreational craft.

• Great Lakes: US Inland Rules, not International COLREGs. Demarcation lines at lake/river entrances define the boundary. Practical difference from COLREGS is minimal for recreational use.
• VHF Ch 16: recreational boats with a VHF must monitor Ch 16 (or Ch 9) while underway when the radio is not in use. Ch 9 for small craft calling. Commercial traffic (lake freighters, tankers) broadcasts position and intentions on VHF, active safety information on narrow channels.
• Nav lights during low visibility (fog, heavy rain), not just darkness. Radar reflectors recommended; required in some commercial traffic lanes. Great Lakes commercial vessels are large and move fast.

• The Great Lakes generate ocean-scale wave conditions. Lake Superior, Lake Michigan, Lake Huron, Lake Erie, and Lake Ontario are all large enough to build storm waves of 15 to 20 feet; NOAA has forecast waves up to 20 feet on the eastern shores of Lakes Huron, Erie, and Ontario. Even moderate lake waves are a hazard for small boats, so check the NWS marine forecast before you go.
• Check NOAA Great Lakes marine forecasts before any open-lake crossing. NOAA's National Weather Service issues marine zone forecasts for each lake in specific geographic zones. Check the forecast for your specific zone, not a general regional weather forecast. Conditions in one zone can differ dramatically from another zone on the same lake. Check for updated forecasts both the evening before and on the morning of departure.
• File a float plan and check in with your marina or someone ashore. Open-lake crossings on the Great Lakes involve distances where cellular service may be unavailable. VHF radio is the primary communication tool. An EPIRB or PLB (personal locator beacon) is strongly recommended for any vessel making open-lake crossings; the USCG response time on open-lake emergencies is longer than in coastal or inland waters.

• Great Lakes wave potential: storm waves of 15 to 20 ft have been forecast (NOAA). Check the NWS marine forecast before you go.
• NOAA marine zone forecasts: check your specific lake zone, not a regional forecast. Check evening before AND morning of departure. Conditions vary dramatically across a single lake.
• Float plan before open-lake crossings. VHF is primary comms where cellular is unavailable. EPIRB or PLB strongly recommended for any open-lake crossing; USCG response time longer than nearshore.

• The Great Lakes have some of the most aggressive invasive species programs in the country. Zebra and quagga mussels, sea lamprey, round goby, Asian carp prevention efforts, and numerous invasive aquatic plants are active management priorities across the basin. USCG, multiple state agencies, and the Great Lakes Fishery Commission all have programs affecting recreational boaters.
• Every Great Lakes state has a mandatory or voluntary inspection program. Michigan, Wisconsin, Minnesota, Ohio, Indiana, Pennsylvania, and New York each have their own inspection and decontamination programs. Requirements vary by state and may include mandatory inspection at specific launch sites, seasonal requirements, or requirements triggered by movement from a known infested water body to a non-infested one. Check the state agency in each state you plan to boat in.
• Canada has its own invasive species requirements on the Canadian side. If you're boating on the Canadian side of the international boundary, Transport Canada and provincial ministry requirements apply. These are separate from US state requirements and may differ in inspection standards and required documentation.
• Do not move live bait between water bodies. Live bait (minnows, leeches, worms) can carry VHS virus (viral hemorrhagic septicemia), which has caused significant fish mortality in parts of the Great Lakes. Many Great Lakes states restrict transport of live bait taken from one water body to another. Purchase bait locally for the water body you plan to fish, or use artificial lures.

• Great Lakes basin: highest AIS management density in the country. Zebra/quagga mussels, sea lamprey, round goby, AIS plants, Asian carp prevention: active programs across all 8 US states and 2 Canadian provinces.
• Every Great Lakes state has an inspection program; requirements vary. Check state agency requirements for each state you'll boat in. Mandatory inspection sites exist in multiple states.
• Canadian side: Transport Canada and provincial requirements are separate from US state requirements. Check before crossing the international boundary.
• Live bait: VHS virus and other pathogens; transport between water bodies restricted in many Great Lakes states. Buy local or use artificial lures.

• NOAA Great Lakes Marine Forecasts (weather.gov/greatlakes): Zone-specific marine forecasts, gale/storm warnings, buoy data; check your specific zone before departure
• CBP Pleasure Boat Reporting (cbp.gov): US-Canada border reporting procedures and CBP ROAM app instructions
• USCG Navigation Center, Inland Rules (navcen.uscg.gov): Full Inland Rules text with Great Lakes-specific commercial vessel traffic provisions