If you want something a little more permanent you can use a hoe to raise land in front of you above water level as you move. It doesn't stop spawns like workbenches and certain other structures, but you will never be without a clear escape path where you have previously treaded. Leeches will also be pretty much powerless to get within reach of you.

Of course there is no reason why it couldn't be used in combination with spawn-blocking structures if you can handle the tedium.