General Resources

American Water Works Association - 25 Facts About Water
History, science, mathematics, and contextual topics of interest around drinking water.

USGS Fact Sheets by State
United States Geological Survey (USGS), Water Resources Divsion, topics and programs of interest by state.
 

Water Quality

Why is Water Temperature Important? | What is Dissolved Oxygen (DO)? | What is pH?
Water Temperature, Dissolved Oxygen (DO), and pH are crucial indicators in water quality measurements. Find out why here.

Water on the Web
"Water on the Web (WOW) helps college and high school students understand and solve real-world environmental problems using advanced technology. WOW is a complete package containing two sets of curricula, data from many lakes and rivers nationwide, extensive online primers, data interpretation and Geographic Information System Tools, and additional supporting materials."

Healthy Water, Healthy People
This water quality education program, sponsored by Project WET and the Hach Scientific Foundation, offers hands-on activity guides, testing kits, training, and much more.
 

Watersheds

E.P.A. - Surf Your Watershed
Provides watershed profiles for all major U.S. river systems. Searchable by map or various geographical text options (such as zip code).

Virtual Vacationland - Watersheds and Rivers
A comprehensive index to informational websites about watersheds and rivers including links to online data sets.
 

Maps and Mapping

TerraServerUSA
TerraServer contains high resolution USGS aerial imagery and USGS topographic maps. You can locate imagery down to 1 meter resolution by clicking on the online map, entering a city or town name, or entering a U.S. street address.

Water on the Web - GIS Quick Start Primer
"This primer covers the basics of using ArcIMS (Internet Mapping Server) - how to get and retrieve information. In the few minutes it takes to read this, you'll learn all you need to know to complete the map-based curriculum exercises in Water on the Web."
 

Phenology

The UK Phenology Network
This comprehensive site visually documents recurring natural phenomena across the UK throughout the year.
 

Invasive Species

USDA, University of Georgia - Invasive and Exotic Insects, Diseases, and Weeds
Comprehensive site on invasive species in the US.

Maine Natural Areas Program - Invasive Plants
Gives a nice overview of what invasive plants are, why we should care about them, and what we can do to help.

Maine Department of Environmental Protection - Invasive Aquatic Plant Images
Maine's 11 most unwanted plants are described.