Cottages For Sale on Big Rideau Lake

Owning a cottage on Big Rideau Lake

Big Rideau is the largest lake on the Rideau Canal, a long, deep trough of water running roughly 32 kilometres from the Narrows to Rideau Ferry. Owning here means you are on a working heritage waterway. Cruisers heading between Kingston and Ottawa pass through all summer, and the canal connects your dock to Smiths Falls, Westport and beyond without ever hauling the boat out.

The lake sits on the Frontenac Arch, so the shoreline is a mix of rock points, wooded slopes, islands and shallow bays. Much of it is still natural. Around the Portland end, about two thirds of the 30 metre strip along the water is woodland. Cottages are thicker near the villages and along the road-accessed stretches, and older seasonal places are steadily being rebuilt as year-round homes.

The water itself is the draw. Big Rideau is deep enough to hold a naturally reproducing lake trout population, which is rare for a canal lake, and it is usually clear. Summers revolve around Portland's marinas, the lake association's day camp on Cow Island, and long evening boat rides. In winter the lake freezes well enough to host an international speed skating event.

• Largest Rideau Canal lake
• Lake trout
• Island cottages
• Portland marinas

History of Big Rideau Lake

Before the canal, Rideau Lake was one long body of water running from present-day Westport down to the rapids at Poonamalie. Lt.-Col. John By first planned to dredge a channel through the shallow Narrows. When that proved too costly, his crews built a dam and lock there around 1830 to 1832. The dam backed up water behind it and split off what is now Upper Rideau Lake. The canal opened in 1832, and in 2007 it became a UNESCO World Heritage Site.

Portland began as a landing on a trail to the lake, where travellers from Brockville switched to barges bound for Perth. Once the canal opened, steamboats and barges carried cordwood, potash, maple syrup and cheese, and the village was later renamed for the Duke of Portland. When commercial traffic faded in the early 1900s, Portland turned to serving the cottagers who were building along the shore. The Big Rideau Lake Association formed in 1911, and Admiral Sir Charles Kingsmill, a founder of the Royal Canadian Navy, kept a summer home on Grindstone Island until his death there in 1935.

The lake's level has crept up over time. The weir at Poonamalie, at the outlet of Lower Rideau Lake, has been raised over the years to keep enough water for navigation downstream. The current weir dates from 1971 and sits about 0.4 metres above the original, which raised Big Rideau and cut the lift at Narrows Lock to under a metre.

Boating on the canal's biggest lake

Parks Canada runs the Rideau as a navigation channel, keeping at least 1.5 metres of draft during the boating season. From Big Rideau you can lock up through the Narrows into Upper Rideau Lake and on toward Westport, or head downstream through Lower Rideau toward Smiths Falls and Ottawa. Expect steady cruiser and rental-boat traffic in July and August, especially near Portland and Rideau Ferry.

This is a big, open lake, and its long axis gives the wind plenty of room to build waves, so match your boat to the water. Shoals are common. The lake association places private shoal markers, and its rule of thumb is to go around a marked shoal rather than between the markers.

Lake trout and the fishery

Big Rideau has been managed as a Class One cold-water lake since 1987, meaning it can support lake trout reproducing on their own. Stocking, mostly of lake trout, went on for about a century and stopped in 2009 because stocked fish were crowding native trout on their spawning shoals. Trout habitat gets squeezed in late summer and early fall when the water warms.

A 2009 provincial netting survey found pumpkinseed and yellow perch most common, followed by brown bullhead, cisco, alewife, rock bass, northern pike and smallmouth bass. Walleye, largemouth bass, crappie, lake whitefish and burbot are also in the mix. The wider catchment holds 27 sport and baitfish species.

Water quality, zebra mussels and Mill Bay

The Rideau Valley Conservation Authority rated Big Rideau's water quality as fair for 2008 to 2013. Phosphorus averaged low, nitrogen stayed within guidelines, and E. coli counts were well under the swimming limit. Clarity averaged about 7.5 metres. Zebra mussels are established and have likely helped make the water clearer by filtering it.

The weak spots are near shore. Most phosphorus readings above the guideline came from shallow sites, including two in Mill Bay at Portland. Septic re-inspections on both the Tay Valley and Rideau Lakes sides recommended repairs on dozens of properties, and emerald ash borer threatens the ash trees along the shoreline and wetlands.

Water levels and your dock

Parks Canada sets the lake level for navigation. The level drops to its winter range in October and peaks in late May, with an annual swing of about one metre. Floating docks or adjustable systems cope best with that range. The conservation authority lists the lake's 100-year flood elevation at 124.51 metres, a useful number to compare against a cottage's floor height.

Because the lake is part of the canal, Parks Canada also reviews in-water and shoreline work. Talk to them and the township before replacing a dock or boathouse.

Portland, Rideau Ferry and Murphys Point

Portland, on Highway 15 along the south shore, is the main service village, with full-service marinas, boat rentals and the Emmanuel Heritage Centre run by the local historical society. Rideau Ferry, at the northeast end, is the other boating hub. Murphys Point Provincial Park sits on the north shore with camping and public access to the lake.

Groceries and larger shopping are in Perth and Smiths Falls. Both towns have a site of the Perth and Smiths Falls District Hospital. Kingston is about 60 kilometres southwest of Portland by road, and Ottawa is roughly 72 kilometres northeast of the lake.