A watershed is an area of land in which all rain and snow runoff and small tributaries drain into a common body of water such as a creek or lake.
The size of a watershed can vary from the land that surrounds and drains into Bear Canyon Creek in South Boulder, to the Mississippi River Basin which collects water from lands to the east and west of the river. The Mississippi River watershed is composed of several thousand smaller watersheds, including the Boulder Creek Watershed, which eventually contributes water to the Mississippi.
Watersheds are a unique framework from which to study water resources issues. Everything that occurs in the watershed affects both the land and the water. By focusing on small, local watersheds like Boulder Creek, we can bring the focus of water quality and quantity issues, which are impacted and affected by the citizens of Boulder, to them, and provide a framework from which relevant management and action can be taken.
DID YOU KNOW?
The Continental Divide is the largest drainage divide in the U.S. All waters that fall to the west of the divide flow to the Pacific Ocean. All waters that flow to the Atlantic Ocean fall to the east side of the divide..... At least in theory. What might be some of the exceptions to the rule?
Poster Paper: to draw watershed of adopted waterbody
1. Look at a city map and find out what body of water (creek, wetland, pond) is near your school.
2. Next, look at a topographic map and see if you can locate the creek or pond on that map (often times topo maps will have major streets and other landmarks).
3. Once you locate the creek or pond, mark where your school is on the map (this will help keep everyone oriented). Also measure out on the map the section that you will adopt this will be the section of creek that you will clean-up, monitor for pollution contamination, watch for wildlife, etc. It can be anywhere from 2 blocks to 1/4 mile long; whatever seems reasonable to your class.
4. Look at the topo map. Can you find the contours lines on it? These lines show the elevation of the landscape. To locate the watershed that your creeks drains, look for the highest ridges or hills around your streamÑthese are the drainage divides. Drainage divides separate one watershed from another.
5. Once you have outlined the shape of the watershed have students locate well-known places such as the school, parks, bikepaths, the grocery store, etc.
6. Determine the direction of water flow (draw blue arrows from the landscape to the water). Which direction does the water flow?
7. If you are looking at a stream in an urban environment, sometimes the stream may disappear it may be piped underground. Contact your local government for maps of the storm sewer system. This will give you information about water supply system in your watershed. Are there ditches connected with your stream? You can learn more about the history of irrigation ditches in Boulder elsewhere in the BASIN website.
Build a relief model of your watershed out of paper mache.