can i use my 1030 for navigation on a canoe trip? is there a way to include water routes?

There is, but you'd have to compile your own maps.  Basically you'd make all the rivers like roads and make the roads and paths unaccessible. That way the Edge would only see the rivers as valid routable options.

wiki.openstreetmap.org/.../OSM_Map_On_Garmin

You'd also need to use a route creation engine that allowed water ways to be used.  You could try BaseCamp with Direct routing and make sure you are careful with where you place the shaping points.

Oh and I see you've specifically mentioned lakes.  In OSM a Lake would be an area, navigation would only work with Lines so the lake would need to have underlying lines/ways that represented the rivers or streams for this to work.  A lot of OSM maps have this already but worth a check before you bother diving in with custom map making.

Someone might have already done this, worth a good old Google.

The Edges all use tracks for navigation.

You can use basic track following. You'll see a purple line and the unit will show you your position relative to it.

If you are on any sort of open water, the routing mentioned above won't work well and would be a fair amount of work to set up.

Thanks I think I’ll buy an inexpensive gps for canoeing.