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Saint Croix National Scenic RiverwayThe yellows of a setting sun are reflected on the water divided by a a dark shoreline
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Saint Croix National Scenic Riverway
Environmental Factors
trees with leaves, with bottom of trunks underwater from flooding

NPS

Spring Flooding

The St. Croix and Namekagon Rivers are always flowing and they are in a constantly shifting, dynamic state. Changing water levels and moving sand drive the change. The land that adjoins the rivers is also dynamic. Weather and climate change, geologic processes, fire, and human-caused factors such as air and water pollution are only a few of the agents of change that have helped to create the Riverway that we know today. The park provides a "living laboratory" that helps us better understand how these environmental factors have shaped park landscapes and ecosystems. Park staff are monitoring changes in environmental factors to alert managers to threats to the resources, hopefully, in time to prevent log term damage to the resources.
A green dragonfly emerges from its old skin, seen below.  

Did You Know?
Dragonflies spend most of their life living in the water. Eventually they climb out of the water and grab onto something. Here they will emerge from their old skin like a butterfly emerges from its cocoon and fly away.

Last Updated: December 11, 2006 at 18:05 EST