Float it off the trailer? That's what I do most of the time.

OR 

If there's no boat launch around, front person grabs the front breasthook - and rear person grabs the transom knees. They all make good handholds.

OR

Get a Seattle Sports boat cart.  It's foldable, lightweight, and you could carry it aboard during your outing. Perfect for one person if you ever go solo rowing.

All three solutions work well for me.

   Thanks, John, all good suggestions, I'll have to take another look at the boat ramp at the reservoir. We have to hand carry our kayaks a ways into the water to launch due to the poor design.