Your lakeside cottage may not be on the waterfront much longer — water levels in the Great Lakes are dropping, and the Mowat Centre says the change could cost $9.61 billion by 2030.

Low Water Blues predicts that tourism and recreational boating and fishing will be the hardest hit sector, losing $12.86 billion by 2050 as vessels are unable to move between lakes and fishing grounds dry up.

Preventing water loss in the Great Lakes has been a concern all the way back to the 1920s, but it has become particularly important as the effects of climate change have led to reduced supplies entering the area. Water levels have been below historical averages since the turn of the century, only rebounding slightly last year thanks to increased snowfall and ice coverage.

Ice levels on the lakes rose to their highest since 1979 this winter according to the report, leading to a demand for more icebreakers and significant shipping delays for already-squeezed grain movers. But the real threat to cargo transport comes from dropping water levels, which the Centre estimates will lead to losses to commercial shipping and harbours of $1.18 billion by 2030:

Declines in water levels in the channels as well as harbour entrances could lower available bottom clearance and force shippers to lighten their loads. This could increase the number of trips required to move a given amount of cargo. Longer-term, this could require additional maintenance on existing vessels as well as capital expenditures to increase the fleet, especially with new vessels shaped to operate in shallower conditions. Additional traffic combined with potential shallowing in key harbours may force speed reductions and stoppages in transit, causing delays in delivering cargo.

Dredging may be the only solution available to ensure continued access and transit through the lakes, but it comes with huge capital costs and isn’t without risks. It might be necessary, though—water transport is the only economically viable option for some cargo.

And you might want to consider selling your lake-view cottage sooner rather than later: Ontario summer home sales were up in May, but the report estimates that property values could drop $976 million through 2050.

Residents of the states and provinces around the Great Lakes could face a more existential threat, with 40 million households relying on the basin for their drinking water. It might be time to invest in that desalination plant.