LOCATION OF SAMPLING STATIONS 

 LOWER COLUMBIA RIVER AREA 



FIG. 9 



Irrigation. Samples collected from station 

 29 on Crab Creek show the nature of the 

 ground water seepage entering the Columbia 

 Basin area itself. Water qxiality data 

 obtained frcm the Columbia Basin irrigation 

 project, stations 27, 28, 32, 33 > 3^, 35, 

 39, end I5, will show the progressive change 

 in water quality as it progresses down the 

 Basin canals, over the land, and back into 

 the canals. Vfenatchee River Basin stations 

 23, hi, 43, hk, 45, and k6 are to provide 

 background data on a river system's queility 

 prior to the construction of a system of 

 dams. (These stations will be discussed in 

 a subsequent report. Plates 1 throxigh 10 

 show these sampling stations.) 



WATER QUALITY CHAJtGES WITH 

 STORAGE OF SAMPLES 



Samples for water quality must be 

 handled in a manner that will insure when 



analyzed, a representative value of the 

 constituent actually present at the time 

 the sample was collected. This necessi- 

 tates the performance of certain techniques 

 at the time the sample is collected. Un- 

 fortunately, many samples cannot be trans- 

 ported back to a laboratory for examination 

 at the convenience of the analyst. All 

 samples must of course be collected in 

 clean containers and be svifficient in num- 

 ber to represent the average conditions in 

 the area sampled. Samples shoiild be stored 

 in the dark to inhibit photosynthetic 

 action in the sample. Examples of special 

 care that must be afforded samples for 

 different analyses follows: 



Temperature : In shallow streams this can 

 be deteimined by wading and immersing 

 a hand thermometer for a direct reading. 

 Reversing thennometers are best for 

 accurate temperature measurements of 

 larger bodies of water but are not 



19 



