Salt Creek Investigation2>
1. You will be making observations on the characteristics of the creek and the surrounding area. Enter all of your observations onto the Illinois RiverWatch Stream Monitoring Data Sheet.
2. Weather conditions: Observe weather conditions today, and also recall and record the weather conditions for the past two days.
3. Collect a sample of water in a beaker. Observe what it looks like. Compare to the appearance of the creek as a whole. Record your observations.
4. Sniff your sample of water. Record your observations.
5. Measure the temperature of the water and the air. Record your data.
6. Observe a 3 foot x 3 foot section of the creek. Estimate how much of the creek bed (the bottom) is covered with algae. Compare this section with two other 3-foot square sections of the creek. Develop an overall estimate of how much of the creek bottom is covered with algae.
7. Observe the entire 50-foot length of our observation site. Estimate how much of the creek is shaded by trees or bushes.
8. Observe the creek bottom. Estimate the percentages of composition of the creek bottom. (Hint: In most of Illinois, you should not observe any bedrock at the bottom of the creek.)
Stream Discharge Estimate
1. You will be measuring the stream discharge estimate, which is how much water flows through the creek in one second. Record your measurements on the Stream Discharge Estimate sheet.
2. First, using string and a yard stick, measure the width of the creek in feet.
3. Leaving the string extended across the creek, use a yardstick to measure the depth of the water at three different points: at one quarter of the distance across creek, halfway across, and three quarters of the way across. Record measurements in feet.
4. To calculate the stream velocity, one student stands 5 feet upstream from the string with an apple or orange in her/his hand. Another student stands 5 feet downstream from the string holding a stopwatch. When the first student releases the fruit into the water, the second student times how many seconds it takes for the fruit to reach her/him. You will need to measure the stream velocity three times at the same three points where you measured the depth of the stream. Calculate the stream velocity by dividing 10 feet by the number of seconds.
5. Calculate the average stream depth and record.
6. Calculate the average stream velocity and record.
7. Multiply the stream width x average depth x average velocity to calculate the stream discharge.
1. You are going to collect, observe and classify macroinvertebrates (bugs without bones) that you find in the creek. Record your observations on the Macroinvertebrate Tally sheet.
2. Locate a riffle in your observation sight.
3. Have two people from your group position the kick net just downstream from the riffle. Make sure the bottom of the net is anchored firmly against the streambed.
4. The other members of the group stand upstream from or beside the riffle and loosen the macroinvertebrates from the rocks. This is done by picking up the rocks, holding them in front of the net, and brushing or "scrubbing" them to remove the organisms. After you have cleaned a rock, place it outside of the sampling area.
5. After you clean off all of the rocks that are 2 inches in diameter or bigger, stand upstream from the net and kick the stream bed to loosen organisms along the bottom of the creek.
6. Carefully remove the net with a scooping motion so you don't lose the critters collected in it. Empty the contents of the net into a pan of water.
7. Use your fingers or forceps to pick up organisms from the pan and place them in a jar of water. Organisms that are too small to collect should be observed using the hand lenses and recorded on the tally sheet.
8. Back in the lab, identify, count and record the organisms you brought back in your jar.
9. Use the formula on the tally sheet to calculate a total cumulative water quality score.