[1] : The Collaborative International Dictionary of English v.0.48

aggrade \aggrade"\, v. t. imp.  p. p. aggraded; p. pr. 
   vb. n. aggrading. phys. geog.
   to bring, or tend to bring, to a uniform grade, or slope, by
   addition of material; as, streams aggrade their beds by
   depositing sediment.
   webster 1913 suppl.
see also:
aggraded aggrading 

[2] : WordNet (r) 2.0

aggrade
     v : build up to a level by depositing sediment ant: degrade
see also:
degrade 

Aggrade >> A Words
Aggrade, definition of term: Aggrade
aggrade_pag1.html