Altering Events
Traumatic experiences (like deforestation and massive flooding) can prompt the river to adopt a new channel, re-occupy an old one, or completely change character. More subtly, variances in the water supply and debris from the watershed to the river can continue to influence river processes and form for decades. Building communities in the uplands, building dams, or leveeing-off floodplains can change the self-governing variables that impact river performance. Even when the event itself is no longer distinct, its impact may endure. For this reason, we say rivers maintain memories.