I lash my gear in all the time, lake/river in any conditions. Last thing a solo paddler needs is to be chasing after or losing gear after you dump.
Many ways to secure your gear from mild to wild. I find a simple line run from bow to center of my seat with carabiners clipped to pack straps will keep packs in in most situations other than swift whitewater.
When you get your swamped canoe into water you can stand in, it's easy to un-clip packs and pull from under line.
I would practice some landing skills before you hit high water/heavy current conditions. I have a painter line for bow and stern, coiled on left/right of my seat. You can use a Velcro strap or some other one hand quick release device to secure while paddling/portaging.
Make it from rope that FLOATS, and has no loops or knots that can snag and overturn canoe if you lose hold of your line.
I'm sure you know this, but for any Newbies, it might be worth repeating. Heading into a current, you can land bow first or better yet, sideways to current/bank. Step out from canoe with bowline in hand and secure it after pulling bow up if possible. If you can't, secure bowline and stern line. This will keep the current from swinging the stern out if you can't land on shore.
Current at your back is a little more tricky, and I bet has dumped more canoes than many will care to admit.
Best bet is to ease as close to shore as you can, pass by the landing, and then back paddle into landing and step out quickly with stern-line. Tie it off if possible, or pull stern up onto secure landing. You can tie off stern and then bow, if your finding yourself unloading on steep bank/rock.
Whatever you do, don't run your bow into landing with a strong current at your back

Once you elevate bow, the current will swing the stern out and over you go. Loose gear and canoe are heading down stream with you either in the water, or running along the bank cursing your stupidity

Bad enough with a tandem canoe/partner or group, but potentially fatal and trip ending when traveling solo.