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ANALYTICAL METHODS  
 

pH A Corning PS 15 pH meter was used and the value was recorded when the reading stabilized.
Conductivity A Casio Data Analyzer EA-100 was used. The two probes were placed 1 inch apart under the water surface. The voltage was recorded when the reading stabilized.
Mass of dissolved solids A 100 ml sample was collected, filtered, and poured into a pre-weighed beaker. The water was allowed to evaporate. The beaker was then remassed and the mass change was recorded.
Mass of suspended solids When filtering the sample to determine the mass of dissolved solids (above), the filter paper was first weighed. Then the sample was filtered. The filter paper was allowed to dry and was remassed. The mass change was recorded.
Air temperature The temperature was measured approximately 4 ft above the water surface. The temperature probe on the Casio EA 100 was used and compared to temperatures obtained with a standard laboratory thermometer. The readings by the two methods were in agreement within one degree. The Casio values are the values recorded in the above table since the students were consistently able to get readings to the tenths place with this instrument.
Water temperature The temperature was measured by submersing the Casio EA-100 temperature probe in the water without touching the bottom of the stream. As describe above, the accuracy was also tested with a standard thermometer agreement of less than 1 degree difference.
Turbidity Fill a clear tube with stream water. Pour out water until you can just see a black washer on the bottom of the tube through the water. Measure the depth of the water in the tube.
Nitrates, Dissolved Oxygen, Phosphates All were measured using Hach brand test kits. 
 
Flow rate 1. Measure distance across the stream.
2. Use a meter stick to determine the water depth in three places going perpendicular to the stream direction. Mark this as your starting position.
3. Go a few meters down stream (measure this distance) and repeat step 1+2. Use this as your ending position.
4. Toss a tennis ball in the water at your starting position and record how long it takes to go from the starting to position.
5. Repeat step 4 three times and find the average of the three readings.
6. Calculate speed in meters per second.
7. Calculate the flow in meters cubed per second.