Welcome to The ReachIt was kind of solemn, drifting down the big, still river, laying on our backs, looking up at the stars, and we didn't even feel like talking aloud.
Mark Twain, The Adventures of Huckleberry Finn 
Contour Farming
Contour farming helps to keep agricultural waste-water and runoff from entering nearby rivers and lakes.

 
Water -
the River of Life

Of all the resources that seem important to us on this planet—food, building materials, books, aluminum, gold, oil—none of them compare to water. Without water, life in all its forms would cease to exist.

In modern times, with the explosion of industrial development, clean water has become more scarce for people living in populated areas. Although the surface of the earth is covered mostly with water, 97 percent of that water is salty, two percent is locked up in the polar ice caps and glaciers, and only a tiny fraction is available for drinking. Thanks in part to the water cycle, fresh water does abound on the surface of our land, ever flowing through the creeks, rivers and lakes of our world. What is most important is that we take care of our water and keep it clean.

Watershed doundary diagramWhere's Your Watershed

Whether you live on a bayou in Louisiana or just downstream of the headwaters of one of Northwest's glacier-fed rivers or in the desert along the Rio Grande, you depend on water; and so does a great host of life that lives with you in your watershed.

Do you know where the boundaries of your watershed are? Find a map of your area and trace the edges of your watershed. Draw a line between your river and the rivers on all sides. This is, generally, your watershed. Do you know who shares the water in your watershed?

If your water comes from a great river, a nearby lake, a small tributary or a well, everything upstream from you may affect your water. Find out who lives upstream from you. And help those downstream by keeping the water that passes you clean.

Bibiocephala grandis - courtesy of North Cascades National ParkBenthic Macroinvertebrates

In recent years, scientists have made a remarkable discovery about how to check water quality, and it doesn't have anything to do with reading specialized meters, testing water chemistry or sending samples off to the lab. In many cases, all scientists need to do is to find out who lives in the water, especially the smaller animals—the benthic macroinvertebrates.

Macroinvertebrate is a term used to describe invertebrates large enough to be seen without a microscope, which includes most aquatic insects, mollusks, arthropods and worms. Researchers count these organisms and compare their numbers with the proportions that scientists have determined should be found there. If the right proportion of species live in the water, things are looking good for that body of water.

Certain macroinvertebrates have high tolerance to pollution. If these species are found in a river in high proportions, it may be that the river is polluted. When scientists check the health of rivers and lakes, they also look for species that are extremely sensitive to changes in water quality. If these species are found in high proportions, it may be good news for all those who live in that watershed.

Kneel down on the bank of your nearby stream and get a closer look. You may be surprised who lives near you.

 
Research and Links

Resources for Freshwater Invertebrate Identification

Voshell, J. Reese. 2002. A Guide to Common Freshwater Invertebrates of North America. The McDonald & Woodward Publishing Company. Blacksburg, Virginia. 442 pages.

Chu, H.F., and Laurence K. Cutkomp. 1992. How to Know the Immature Insects. WCB McGraw-Hill. Boston. 346 pages.

Merritt, R. W., and K.W. Cummins. 1996. An Introduction to the Aquatic Insects of North America. Kendall/Hunt Publishing Company. Dubuque, Iowa. 862 pages.

Some useful and fun websites

The National Park Service hosts a water resources web site. By entering the "water and information" section, you can get a report on water quality at any National Park Service unit.

RiverLink is a regional non-profit spearheading the economic and environmental revitalization of the French Broad River and its tributaries as a place to work, live and play.

The Alice Ferguson Foundation site allows students to do virtual dip netting and take a tour of the water cycle. Geared towards 5th grade.

The National Aquatic Monitoring Center has a photo ID guide to stream macroinvertebrates on their web site.

The Izaak Walton League of America organizes the Save our Streams campaign. They have several useful teacher resources on sale from their web site.

The Stream Study web site has an online, interactive, macroinvertebrate key. A good resource if you have the critters in hand.
 

Classroom Information

Hands on the Land Teaching Resources on water and watersheds.

Glossary: bioassessment, benthic, macroinvertebrate, taxa, richness, EPT richness, depositional, erosional, seep, detritus, trophic group, riparian zone, aquatic macrophyte, primary production, shredder, predator, scraper, filterer, collector-gatherer, decompose, headwaters, tributaries

Return to Hot Topics.
Bureau of Land ManagementUS Fish and Wildlife ServiceUSDA Forest ServiceUSDA Natural Resource Conservation ServiceNational Park ServiceNational Oceanic and Atmospheric AdministrationEnvironmental Protection Agency