What is a Watershed? Lesson Plan Outline

What is a Watershed?

(Designed for locations within the Pajaro Watershed)

Focus:

• Features of the local watershed
• Water quality monitoring techniques
• Connection between healthy watersheds and healthy marine environments
• Community actions that support watershed health
• Ecological restoration
• Downstream effects of non-point source pollution on aquatic life

Materials:

Recycled paper, water-based markers, PPT introducing aquatic invertebrates

Alternate activities such as the human watershed modeling activity (see pdf) or the watershed model available through NOAA will require other or additional materials.

Procedure:

Facilitate discussion of some of the ways we use water.

10 ways we use water (list)

**On the average in the U.S., a person uses 100 gallons of water a day
**A dairy cow must drink 3 gallons of water to produce 1 gallon of milk
**An ear of corn needs 26 gallons of water to grow
**A meal at a fast food restaurant can take 1,400 gallons of water to make (burger, fries and drink)

Where does it come from?

Eighty-five percent of Watsonville’s water supply is groundwater, primarily taken from the Aromas Red Sands Aquifer. The Aromas Red Sands Aquifer underlies the Pajaro River Water Basin. The aquifer also supplies other water agencies in the region. The Watsonville water system consists of:

• 12 inland water wells spread throughout the Pajaro Valley ;

• Brown Creek and Corralitos Creek;

• five small lakes (Pinto, Kelly, College, Drew, Tynan);

• the Pajaro River;

• the Grizzly Flats upper watershed, which has 215 acres of land to draw water

from; and

• Harkins Slough.

--Write the word Watershed on the board.  Ask learners for definitions. Provide a simple definition for a watershed – a body of land that drains into a river, lake, or other body of water. (Note: Boundaries are high points of land that slope downward towards the body of water). 

--Do the following activity to demonstrate what a watershed is:

• Crumple a piece of paper into a loose ball.
• Partially open the paper, and place it on a desk. The paper should still be crumpled enough to have portions that resemble mountain ridges and valleys.  Be sure there is a paper towel under the paper.
• Using a blue water-based marker, have students mark “creeks” or rivers on their papers, and also have them mark where they think the water will collect as it runs downhill. (this could represent a lake).
• Using a black water-based marker, have learners outline the ridges that separate one creek or river from another.
• Using brown water-based markers, have learners draw exposed soil that could erode or wash away into the lake as the water flows through the watershed.
• Using red water-based markers, have learners draw in some pollutants that may be found in their watershed, such as soap from washing cars, pesticides from lawns, and animal waste from a nearby farm.
• Keeping the model on the desks, have learners spray (or you go around with a sprayer and spray) a very light mist of water over it.
• Observe where water runs down and collects. 
• Ask the learners: If this is a model of a watershed...
• What does you suppose the paper represent?
• What does the mist/spray represent?
• What does the water that runs down into the creases represents?
• Why does water flow down into the creases?
• What does the water flowing in the creases represent?
• What does the water that “pools up” represent?
• What happened to the ink from the markers as the water flowed?
• Where will the ink eventually end up (the highest or lowest place in the watershed)?
• How is this a problem if the inks represent pollutants?”
• Ask learners to consider how this is similar to and/or different from local areas. Where in the community would there be the most pollutants?

Begin Aquatic Insect PPT Presentation

Introduce stream insects (‘aquatic macroinvertebrates’) and explain how they help indicate whether a stream has been affected by pollution.

The presence of aquatic insects that are highly sensitive to pollution can serve as indicators of water quality (example, stonefly nymphs cannot tolerate low levels of oxygen).

Some aquatic insects are less sensitive to pollution (example, giant water bug).

Introduce field trip locations:

Upper Watershed, Grizzly Flat

Journal Prompt:

What is my impact on the watershed?

Some of the materials in this lesson plan were modeled after Watershed S.O.S. (Saving our Sources) available at http://learningtogive.org/lessons/unit382/

Alternative Outline for incorporating Human Watershed Activity appropriate to Pajaro Valley region:

What is a Watershed?

a body of land that drains into a river, lake, or other body of water. (Note: Boundaries are high points of land that slope downward towards the body of water). 

Human Watershed Activity

Start: Which mountains form the boundary of our watershed? (Santa Cruz Mountains)

Where does it drain?

What’s special about the Monterey Bay? (Nat’l Marine Sanctuary)

Arrange yourselves to form a watershed. (including organisms)

Hand out objects to represent a pollutant (POP- persistent organic pollutant)

            -Where will it end up?

The Pajaro River mainstem begins just west of San Felipe Lake, also called Upper Soap Lake, a 9,000-acre floodplain on the Santa Clara and San Benito County border; the floodplain of the Upper Pájaro River and functions as a natural detention basin that greatly reduces the peak of floods many miles downstream in the towns of Watsonville and Pájaro. It is a natural (though degraded) migration corridor for animals and birds moving between the Santa Cruz Mountains and the Mount Hamilton Range. The Pajaro River mainstem flows west for 30 miles (50 km), passing the city of Watsonville and emptying into Monterey Bay.

Pinto Lake drains into Corralitos Creek then into the Pajaro River

Introduce stream insects (‘aquatic macroinvertebrates’) and explain how they help indicate whether a stream has been affected by pollution.

The presence of aquatic insects that are highly sensitive to pollution can serve as indicators of water quality (example, stonefly nymphs cannot tolerate low levels of oxygen).

Other aquatic insects are less sensitive to pollution (example, giant water bug).