Waterfront on a federal waterway comes with questions an inland home never raises. These are the ones Kimberly works through with every Sparrow Lake buyer, early, before conditions run out.
Where the lot ends
Parks Canada owns and has jurisdiction over the bed of the Trent-Severn Waterway up to the original upper controlled water elevation, and a title search is needed to confirm how far a property’s ownership extends (Parks Canada, n.d.-b). Your lawyer, and a surveyor where needed, should confirm it before you firm up.
Shore road allowances
Many lots were laid out with an original shore road allowance between the lot and the water. Gravenhurst has sold sections of the shore road allowance on Sparrow Lake to abutting owners (Town of Gravenhurst, 2024). Ask whether the allowance in front of the lot has been closed and bought, or is still public.
Docks, boathouses and shoreline work
All work on, under and over the bed and waters of the waterway needs a Parks Canada permit, including docks, boathouses, boat lifts, shoreline stabilization and dredging, and no in-water structure is grandfathered (Parks Canada, n.d.-b). Severn also requires a building permit for docks and boathouses, with the Parks Canada permit first (Township of Severn, n.d.-a). Gravenhurst requires a building permit for a dock connected to the shoreline and a site plan for exterior projects (Town of Gravenhurst, n.d.-b). Ask whether existing structures were permitted.
Water level and high water
Parks Canada coordinates outflows from Lake Simcoe and Lake Couchiching with the Black River to reduce the threat of high water on the Severn River and Sparrow Lake (Parks Canada, n.d.-f). In 2026, high water and flows delayed the opening of Locks 42 to 45 until May 29 (Township of Severn, 2026). Ask the sellers how the dock and shoreline handle spring water.
Septic and water systems
A private septic system and water source come with most properties. In Severn, the discretionary septic re-inspection program that covered Sparrow Lake was suspended at the June 17, 2026 Council meeting (Township of Severn, n.d.-c). Gravenhurst runs a summer septic re-inspection program (Town of Gravenhurst, n.d.-b). Ask for permit records, and make inspection and water testing part of your conditions.
Which township, which rules
The Lake Simcoe Region Conservation Authority’s area does not include Severn or Gravenhurst (Lake Simcoe Region Conservation Authority, n.d.), and Muskoka has no conservation authority (Muskoka Watershed Council, 2012), so shoreline approvals run through Parks Canada, the municipality and, for some work, the province. Kimberly confirms which apply to the specific property.
Kimberly is a REALTOR®, not a lawyer, surveyor or permitting authority. This checklist is a starting point for your own due diligence with those professionals and agencies.