while the stream adjusts to the in^osed 

 conditions. 



3. The influence of artificially 

 created compaction caused by driving a 

 temporary standpipe into the streambed is 

 el iminated. 



This paper gives cin account of the 

 adaptations in design of the placed stjind- 

 pipe developed at the Mill Creek Fisheries 

 Station in California and at the laboratory 

 of the U. S. Bureau of Commercial Fisheries 

 in Seattle. Specifically the presentation 

 describes: 



1. Innovations in the design of the 

 standpipe. 



2. How to derive rates of flow of 

 water through the gravel in feet per hour 

 from the calibration of the standpipe in 

 the laboratory. 



3. Methods developed for sampling 

 the streambed by use of the standpipe. 



4. Some comparisons of rates of flow 

 of water and of amounts of dissolved oxygen 

 in the streambed with the survival of king 

 Salmon eggs. 



chemicals, solves the problem of corrosion. 

 Eliminating corrosion has advantages besides 

 preventing the deterioration of the device 

 itself: providing samples of water free 

 of both oxidizing impurities and suspended 

 silt; both precautions are recommended in 

 the determination of dissolved oxygen by 

 the Winkler method. These and other advan- 

 tages that will be discussed later in the 

 article are made possible by use in the 

 standpipe of a free-moving, noncorroding 

 sleeve, which functions as a valve. 



The parts and assembly of the poly- 

 vinyl chloride plastic standpipe used at 

 Mill Creek are illustrated in figure 1. 

 The plastic comes in all forms — including 

 pipe, pipe fittings, sheets, and cylindri- 

 cal bars — and is easily shaped on a lathe. 

 The sleeve is made from 1 1/4-inch pipe 

 stock, which fits into the 1 1/2- inch 

 milled shaft. The inside diameter of the 

 lower 5 inches of the shaft is increased 

 to a generous 1 5/8 inches, and the outside 

 of the sleeve is turned down to a skimpy 

 1 5/8 inches. A silicone paste applied to 

 these parts creates a seal and supplies 

 lubrication for free movement. The foot- 

 like attachment at the base anchors the 

 pipe securely in the streambed to forestall 

 washout . 



ACKNOWLEDGMENTS 



The authors wish to acknowledge the 

 assistance received by Robert D. Broad who 

 participated in the development of the 

 Mill Creek Standpipe, R. G. Hennes, Profes- 

 sor of Civil Engineering, University of 

 Washington, who served as consultant, and 

 Glenn Pedersen who reviewed the presenta- 

 tion. 



The illustrations were prepared by 

 Virginia Coleman, 



INNOVATIONS IN THE DESIGN OF THE 

 MILL CREEK STANDPIPE 



To keep a standpipe operational for 

 prolonged periods of time in an open stream 

 requires use of special materials and 

 design. Some of the hazards that must be 

 overcome are corrosion, plugging of the 

 staindpipe with silt, and washouts. A plas- 

 tic material, polyvinyl chloride, which is 

 very durable and resistant to water and 



The valve generally is trouble free; 

 however, a grain of gravel may lodge in 

 two of the alined holes and subsequently 

 prevent free movement of the valve. This 

 difficulty has occurred on occasion but has 

 not proved to be serious; nevertheless, 

 duplicate installations are desirable as a 

 Safeguard. Duplication also provides more 

 reliable data. 



The standpipe separates into two 

 parts: the main shaft and the extension 

 tube. After the measurements have been 

 taken, the extension tube is removed and 

 the shaft is capped and left imbedded in 

 the gravel. Since the shaft of the stzuid- 

 pipe protrudes only slightly above the 

 gravel, it is moderately safe from drifting 

 objects and from the force of water occa- 

 sionally moving at high velocities. 



The lower 4-inch section of the shaft 

 is grooved to lessen the chance of stopping 

 a hole in the lower perforated section by 

 a stone that may be pressed flat against the 

 standpipe over the hole. 



