The Collaborative International Dictionary of English v.0.48:

Seep \Seep\, or Sipe \Sipe\, v. i. [AS. s[imac]pan to distill.]
   To run or soak through fine pores and interstices; to ooze.
   [Scot. & U. S.]
   [1913 Webster]

         Water seeps up through the sidewalks.    --G. W. Cable.
   [1913 Webster] Seepage

The Collaborative International Dictionary of English v.0.48:

Sipe \Sipe\ (s[imac]p), v. i.
   See Seep. [Scot. & U.S.]
   [1913 Webster]