Question
I live in Vancouver, BC and our very weather is a bit of a problem.  I moved into this house last summer, we tore up a concrete backyard and laid sod.  It was beautiful last summer, grew so fast we couldn't keep up with it.  over the winter it has gotten very soggy and I am concerned about poor drainage.  I have heard that putting sand over it will help, but I don't know how much or when.  I am also concerned about insects/mosquitos/flies as the wet spring season begins.  

Answer
Sanding a lawn will not improve drainage. This is a misunderstanding. Golf course supervisors will sand fairways to ensure water penetration rather than runoff. Also, a heavy clay soil can be improved by core aerating and then filling cores with sand. Over a long period of time the soil can in this manner gradually be improved, but it is not a quick fix for soggy lawns. It helps improve the general soil structure - in time - but is no solution to existing problems.

A soggy lawn in the PNW is not uncommon, however, and you should probably wait and see how well it performs this spring and summer before taking any drastic meassures. If the lawn rots due to standing water, you may have to rip it out, install drainage tiles, and re-sod / re-seed. I would give the lawn a chance first, however, before resorting to these drastic meassures.