
by Naomi White, Science Teacher, Jefferson High School, LAUSD
LESSSON SHEET [ Sampling Sites | Student Research Water Quality Data Sheet ]
Time Frame: one period to make water sampler
Materials:PVC pipe, 2 1/2 meters (8 foot length)
beer or similar type bottle
cork or stopper to fit bottle
string, 3 meters
duct tape
indelible ink markerProcedure:
Techniques for Taking Water Samples:
- Stand the PVC pipe upright.
- Securely tape the bottle to the bottom of the pipe with the ducttape so that the bottle bottom is even with the bottom of the pipe.
- Tightly fasten the string to the stopper.
- Measuring from the top of the bottle, mark the pipe along thefollowing intervals: 2 cm, 10 cm, 50 cm, 100 cm, 200 cm
- When taking a sample, make sure the bottle has been rinsed severaltimes with the water from the test site. Plug the bottle with the stopper.Submerge the pipe to the desired depth. Tug the string to open and fill thebottle.
- Always use gloves and goggles in possible polluted sites.
- Whenever possible, take sample from the middle of the body of waterat about middle depth using a boat or bridge. Collect samples from localbodies of water such as reservoirs, manmade ponds, lakes, or rivers.Collect several liters at each site in order to run all the tests.
- Temperature, pH, carbon dioxide, and oxygen content tests should bedone as soon as possible at the test site. Keep water samples for test tobe done in the laboratory in a cool location.
- Retest in a few days especially before and after a rainstorm, ortest in a different locationalong a river or creek.
Los Angeles River Connection is a part of LAEP Learning Exchange.