smoothing question.
 

I have a surface around 200 pollies this surface is bumpy in the sense that the vertexes are uneven. I would like to take the average hight (z) and set all vertexes the same, in a sense smoothing the plane along with applying a curve. So that my result is a concave or convex smoothed surface. Is there a tool hidden with in the depths of Maya that does such a thing?

I can get a smooth plan with the scale tool but I cant use the sculpt tool on selected vertexes.