Big Creek Reserve
Water Quality Chemical Data Procedures:

Calibrate monitor(s) and check batteries at least every 6 months.
Change pH wand fill solution every 2 months. The DO sensor should always be stored with either distilled water or DO fill solution in the cap over the tip. The pH meter should always be stored with 7.0 buffer solution in the cap over the tip.


Locations of sites:
BE is at the Big Creek beach area, just below and downstream of the Highway 1 arch bridge.
BC is at the large pool in the Big Creek fork, just before the creek joins Devil's Creek.
DC is at the base of the trail to the confluence, on the south bank of Devil's Creek, just above the footbridge and before Devil's Creek joins with Big Creek.

Before taking measurements:
" Examine DO sensor tip for bubbles and corrosion.
For bubbles: with the meter and the sensor apart, unscrew the sensor tip. Holding the membrane unit facing upward, fill to the top with sensor refill solution (in "checkmate" case, plastic dropper with snap-off tip). Tap the sides gently to help dislodge bubbles. Holding the sensor vertical above the membrane tip, screw the tip into the membrane. Invert the unit and examine the membrane for bubbles again. If there are bubbles, repeat the procedure.
For corrosion: unscrew the tip, scrub it with the buffer (white porous strip in checkmate case) until unit is shiny. Refill tip with solution as for bubbles, above.
" Polarize DO meter: With the meter off, plug DO sensor into the meter for at least 3 hours, preferably overnight, before use.
" Check the pH kcl solution. If the sensor is filled up to the black rubber plug near the top of the clear section, it's ok. If it is low, refill it with kcl solution from the "checkmate" case. Reclose the unit firmly with the black rubber plug.

To take measurements:
1. Place the thermometer in a shady location.
2. Write down location, time, date, tester, and weather data on data sheet.
3. Take conductivity measurement: place tip in stream area where there is a consistent, gentle flow and turn meter on. Write down final readout before turning the meter off. REMEMBER TO TURN IT OFF.
4. Attach the probe to the pH meter. Remove the wetting cap and place it right side up in the "checkmate" case. Briefly unplug the black rubber plug at the top of the sensor body. REPLACE THE PLUG. Place the sensor tip in an area of the creek with a gentle, consistent flow and turn the meter on. It will beep when it is done. Write down the measurement before turning it off. REMEMBER TO TURN IT OFF. Put the wetting cap back on the tip. Unplug the sensor from the meter and replace it in the "checkmate" case.
5. Read the air temperature and write it down.
6. Place the thermometer in the creek until the temperature has stabilized and record the temperature on the data sheet.
7. Remove the tip from the DO sensor without twisting it. Check for bubbles. Place the tip in the water and press the button labeled "read," then press "mode." Check the display to be sure that the measurement will be in mg/l. The reading will stabilize and stop before the water temperature has an accurate reading, so using the previously recorded water temperature as a guide, continue to press "read" until the meter registers a temperature of <.6*C greater than the true temperature. Write down final DO measurement. Turn off the meter by pressing "mode." Replace the wetting cap, adding solution if necessary. Leave the sensor plugged into the meter until the last location has been monitored.
8. Take a water sample for measuring turbidity later.
9. Make notes of anything unusual that might have affected the measurements.
10. Repeat the above steps 1-9 at the next two locations.
11. Record the depth as you drive by the staff gauge. Binoculars will be needed.
12. Take all 3 turbidity samples to the lab. Fill one plastic tube from the LaMotte turbidity kit with distilled water or Whale Point tap water. Fill the other with water from one of the creek samples. Use the 50ml fill line for fairly clean creek water, use the 25ml fill line for dirty water. If there is a difference between the creek water and the other water, shake the turbidity reagent and add .5ml to the distilled/lab water. Stir it with the rod provided. If the altered water is cloudier than the creek water, the turbidity measurement is <5JTU. If the water is less cloudy, add another .5ml of reagent and calculate accordingly. Record the measurement. Rinse both tubes. Repeat for next two samples, being sure to shake the reagent every time it is used. Rinse and dry the tubes when done. Dispose of leftover creek water and rinse and dry the sample bottles. Put the empty bottles back in the "checkmate" case.