siltation

noun

1. (uncountable, usually)The (typically undesirable) increase in concentration and or of deposition of water-borne silt in a body of water.

   “They are also heavily engineered upstream: a dam built upstream in neighboring India can critically stanch the flow of freshwater down here, increasingly the chances of salinity and siltation.”

   “The roster of perils includes, but is not limited to: overfishing, which promotes the growth of algae that compete with corals; agricultural runoff, which also encourages algae growth; deforestation, which leads to siltation and reduces water clarity; and dynamite fishing, whose destructive potential would seem to be self-explanatory.”