Cumulative Effects

Additive, synergistic, interactive or nonlinear outcomes of multiple development or disturbance events that aggregate over time and space.”   Examples of cumulative effects may include: reduction of water flows in a watershed due to multiple withdrawals; increases in sediment loads to a watershed over time; interference with migratory routes or wildlife movement; or more traffic congestion and accidents due to increases in vehicular traffic on community roadways.

(Adapted from Biodiversity Impact Assessment. Special Publication Series No. 3, International Association for Impact Assessment, July 2005, with examples from IFC PS 1, page 4, footnote 16).