Investigations of methods and equipment used in stream gaging

MISSING IMAGE

Material Information

Title:
Investigations of methods and equipment used in stream gaging
Series Title:
Geological Survey water-supply paper ;
Physical Description:
iv, p.37-75 : ill. ; 23 cm.
Language:
English
Creator:
Pierce, C. H ( Charles Henry ), b. 1878
Geological Survey (U.S.)
Publisher:
U.S. Govt. Print. Off.
Place of Publication:
Washington
Publication Date:

Subjects

Subjects / Keywords:
Flow meters   ( lcsh )
Hydraulic engineering -- Instruments   ( lcsh )
Stream-gaging stations   ( lcsh )
Hydraulique -- Ingénierie   ( ram )
Débitmétrie   ( ram )
Genre:
federal government publication   ( marcgt )
non-fiction   ( marcgt )

Notes

Additional Physical Form:
Also available in electronic format.
Statement of Responsibility:
by C.H. Pierce ; prepared in collaboration with the Hydraulic Laboratory Committee of the Geological Survey.

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 030834339
oclc - 20553176
Classification:
lcc - TC801 .U5 no.868-B
System ID:
AA00026212:00001

Full Text









UNITED STATES DEPARTMENT OF THE INTERIOR
Harold IA Ickes, Secretary
GEOLOGICAL SURVEY W. C. Mendenhall, Director


Water-Supply Paper 868-B




INVESTIGATIONS OF METHODS

AND EQUIPMENT USED IN

STREAM GAGING




PART 2. INTAKES FOR GAGE WELLS

BY
C. H. PIERCE



Prepared in collaboration with the
HYDRAULIC LABORATORY COMMITTEE
OF THE GEOLOGICAL SURVEY
LAurLny LEE. C. H. PIERCE, and O. W. HARrWELIL, members















UNITED STATES
GOVERNMENT PRINTING Oi'IC
WASHINGTON : 1941

w $iai alsb the Superiaitendent of Doenn ents, Washington, D. C. Price I ceits












CONTENTS

Page.
Abstract ----------------------------------------------------- ---- 37
Introduction ------------------------------------------------------- 37
Administration and personnel --------------------------------------- 38
Cooperation and acknowledgments ----------------------------------- 39
Purpose and scope of the investigation ------------------------------- 39
Intake devices selected for laboratory tests --------------------------- 39
Standard pipe fittings attached to end of intake pipe -------------- 40
Standard pipe without fittings ----------------------------------- 40
Other devices ------------------------------------------------- 41
Methods of tests -------------------------------------------------- 42
Laboratory equipment for tests of Ye-scale models --------------------- 43
The A models ------------------------------------------------------ 44
Full-size models --------------------------------------------------- 54
Apparatus used in tests of the full-size models -------------------- 54,
Distribution of velocity in the 3.0-foot flume ----------------------- 5&
Models selected for tests ---------------------------------------- 56;
Tests --------------------------------------------------------- 58
Collection of deb-ris on intake ------------------------------ I --------- 66
Removal of silt by flushing ----------------------------------------- 66
Flushing apparatus -------------------------------------------- 67
Tests --------------------------------------------------------- 67
Results of the investigation ----------------------------------------- 68
Recommendations for designs --------------------------------------- 69
Static tubes --------------------------------------------------- 69
Baffles ------------------------------------------------------- 73
Other devices ------------------------------------------------- 75



ILLUSTRATIONS

Page
PLA.TF, 28. A, Flume used in test of the A models; B, Model --age well,
mounting block, and support, with model A-39 in position
for test ----------------------------------------------- 44
29. A, Draw-down in, manometer wells under the point gages in
test of model A-39; B, Tests of model A-79 under a velocity
of 2.8 feet'per second ---------- I ------------------------ 45
30. A, Outlet of 3-foot flume; B, Piezometer gages and stilling
well for the 3-foot flume -------------------------------- 68
31. A, Eisenlohr intake box; B, Kinnison intake box ------------ 69
FIGURiz 4. Distribution of velocity in the 3-foot flume for a velocity of 2.8
feet per second at the intake ---------------------------- 56
5. Designs of static tubes for use with 2-inch, 2%-inch, 3-inch,
and 4-inch intake pipes --------------------------------- 70
6. Static-tube connection to intake pipe of gage well at streamflow measurement station provided with artificial control- 7"
7. Design of Ash baffles for intake pipes of various sizes -------- 73 8. Design of Twitchell baffles for intake pipes of various sizes --- 73 9. Design of Eisenlohrl intske box ---------------------------- 74
In






IV CONTENTS

TABLES


TABLE 1. Intake devices selected for laboratory tests ------------------ 40
2. Dimensions of standard sizes of pipe --------------------- I 45
3. Dimensions of A models --------------------------------- 45
4. Results of tests of A models under a velocity of 2.8 feet per
second ------------------------------------------------ 47
5. Tests of selected A models under various velocities ---------- 50
6. Full-size models selected for tests -------------------------- 56
7. Tests of full-size models of 3-inch intake devim ------------ 60
8. Comparison of tests of full-size models of devices for use with
various sizes of pipes at a velocity of 2.8 feet per.:second- 62
9. Tests of Twitchell and Ash baffies of various lengths with different sizes of pipes ------------------------------------ 63
10. Effects of collection of debris on intake -------------------- 66
11. Flushing tests of intake devices for 3-inch pipe -------------- 68














INVESTIGATIONS OF METHODS AND EQUIPMENT

USED IN STREAM GAGING


PART 2. INTAKES FOR GAGE WELLS


By C. H. PIERCE


ABSTRACT

Various devices attached to the ends of intake pipes to gage wells have been used by engineers of the Geological Survey in attempts to eliminate the "drawdown," or difference in the heights of water in the well and in the river stations for the measurement of stream flow. About 90 different devices and arrangements of intakes were tested at the National Hydraulic Laboratory in order to obtain definite information regard ng the performance of the various devices and their eff6ctiveiiess in eliminating draw-down.
Preliminary tests were made of Yscale models, an intake pipe 3 inches in diameter being taken as the basic size, with water flowing at 2.8 feet per second at the intake. Models that gave good results in the preliminary tests were selected for additional tests at full size. The models were tested for different positions corresponding to angularity of flow of the water passing the intake as well as for the normal position of intake perpendicular to the vertical plane in the direction of flow. The results of the tests of the %-scale models and the full-size models are givenin the tables.
As a result of the tests, several different devices were selected by the laboratory committee of the Geological Survey for recommendation to the district engineers of the Survey as being effective in eliminating draw-down at stations for the measurement of stream flow. Designs for use in constructing the devices are shown in the illustrations.

INTRODUCTION

Ile general use of water-stage recorders in obtaining records of stream flow has tended to the development of certain types of struc,tures specially adapted to the purpose of providing shelter for the "-* the necessary facilities for their recording instruments and L
operation.. The instruments are installed over st wells. which
axe designed to eliminate the dynamic disturbances, such as the effects of wave action and pulsations, commonly found in natural streams, and to maintain a height of water that will be the same as the static head of the water M.' the stream channel or have a direct relation to it. If the ot weR is constructed in the bank of the river for protection
against damage by floods or by freezing, a connection between the 37





38 MIEMOD13 AND EQUIPMENT USED IN 8TRICAM GAGING

water in the river and the water in the well is made by means of an intake pipe. These intake pipes may be from 2 to 4 inches in diameter and of various lengths depending upon the distance from the stilling well to the point in the river at which the height of the water. sutfam is to be, measured. Unless the stream end of the intake pipe Is' protected from the dynamic effects of the water flowing past it there may be a draw-down or a building up of the height of water in the well as compared with the height of water in the river channel at the end of the pipe. These differences in height have been found to be as much as 1 foot, and they vary not only for different stages but they may also vary for the same stage of the river. Stilling wells attached to bridge piers or abutments are generally provided with small openings whereby the water is admitted directly into the wells without the use of intake pipes. Under those circumstances the dynamic effects ,of the water may be even more pronounced than those experienced where the connection is made through intake pipes. Except in rivers where heavy silt loads make the use of intake pipes impracticable it is possible that intake connections to stilling wells on bridge piers ana abutments might be made in a manner similar to that used with stilling wells in river banks.
Various devices attached to the ends of intake pipes have been used by engineers of the Geological Survey in attempts to eliminate the so-called "draw-down," or difference in the heights, of the water in the well and in the river at stream-flow measurement stations, and in October 1936 a letter was sent to all the district engineers of the Survey requesting suggestions in regard to designs of intake devices to be used in a series of tests in order to obtain information as to the most satisfactory devices. A large number of suggestions were received in response to that letter, and arrangements were made with the National Bureau of Standards for the use of its laboratory facilities in making a series of comparative tests of the devices that had been suggested.
ADMINISTRATION AND PERSONNEL
The work in the laboratory and office incident to the preparation of this report was performed under the general administrative direction of N. C. Grover, chief hydraulic engineer and C. G. Paulsen, act' chief hydraulic' en ineer after the retirement of Mr. Grover on January 31, 1939. Mr. Paulsen also administered the work as chief of the division of surface water.
The methods and procedures used in conducting the investigation were arranged by the. hydraulic laboratory committee of the waterresources branch of the Geological Survey, consisting of Lasley Lee, C. H. Pierce, and 0. W. Hartwell. H. C. Beckman and C. V. Youngquist became members of the committee after the death of Mr. Lee






INTAKES FOR GAGE NVIDLLS 39

in November 1937. Laboratory tests of the Y8-scale models were made by Messrs. Lee, Pierce, and Hartwell, assisted by W. S. Eisenlohr, Jr., and A. D. Ash. Tests of the full-size models were made by Mr. Eisenlohr., The. analyses of tke data and the recommendations based on the results of the tests were made by the laboratory committee assisted by Mr. Eisenlohr.

COOPERATION AND ACKNOWLEDGMENTS
The facilities of the NationaJ Hydraulic Laboratory were pTovided by the National Bureau of Standards. The laboratory staff under the direction of H. N. Eaton furnished advice and assistance in the conduct of the work, particularly in regard to details of laboratory procedure.

PURPOSE AND SCOPE OF THE INVESTIGATION
The investigation was arranged for the purpose of testing the various designs: of -Mitake devices that haff"been suggested by engineers of the Geological Survey as being helpful in eliminating the effects of drawdown in gage wells. Some forms of intakes were tested for the pur pose of obtaining standards of comparison rather than because of the merits of the particular forms. Tests of the draw-down when using a straight pipe wiith the outer end square-cut and open to the action of the water were made for purposes of comparison. Most of the models tested were composed of standardpipe fittings or accessories that could readil constructed in the field.
y be obtained or
A few models of more complicated design were constructed for purposes of tests.
The tests were made with water passing the intake at velocities of 1.0) 2.01 2.8,. and 3.65 feet per second. The limitations of the water available for testing the full-size models in the large flume did not permit the use of higher velocities.

INTAKIR -DEV CES, SELECTED FOR LABORATORY TESTS
The estions as to forms of intake devices received from the
engineers of the Geological Survey were arranged for use in the series of tests all the suggestions that were sufficiently specific and practicable for laboratory tests being included. Several other devices and uTaingements of pipe fittings were selected by the laboratory committee, so that a total of about 90 different devices and arrangements were prepared for tests. The different devices and arrangements are listed below.' The dimensions given are those for use with an intake pipe 3 inches in diameter.

I The serial numbers used in this list have been roarranged from those originally assigned to the various devices.







40 METHODS AND 'BQU1PM9Nvr UBED 'M RMEAM (;A(IING

T,&IBLE L-Intakis devim seleded for labora4ary t*81a
STANDARD PIPE FITTINGS ATTACHED TO END OF INTAKE PIPE
1. 90' elbow with open end pointing upstream.
2. Same as I, except the open end pointing downstreamti'.
3. Same as 1, except the open end pointing downward.
4. 45' elbow with open end pointing upstream. ,5. Same as 4, except the open end pointing downstream.
6. Same as 4, except the open end -pointing downward.
7. Tee, with run on intake pipe, the outlet pointing upstream.
8. Same as 7, except the outlet pointing downstream.
9. Same as 7, except the outlet pointing downward. 10. Same as 7, except the outer end of run plugged. 11. Same as 7, except the outer end of run plugged and the outlet pointing downstream.
12. Same as 7, except the outer end of run plugged and the outlet pointing downward.
13. Same as 7, except with a 12-inch nipple in outlet pointing upstream. 14. Same as 7, except with a 12-inch nipple in outlet pointing downstreani. 15. Same as 7, except with a 12-inch nipple in outlet pointing downward. 16. Same as 7, except with a 12-inch capped nipple on tfie 'outer end of the run, 17. Same as 7, except with a 12-inch capped nipple on the outer end of the run
and the outlet pointing downstream.
18. Same as 7, except with a 12-inch capped nipple on the outer end of the run
and the outlet pointing downward.
19. A 4-inch to 3-inch reducing elbow with the 4-inch opening pointing downward. 20. A 3-inch to 2-inch reducing elbow with the 2-inch opening pointing downw&Td. 21. A 4-inch to 3-inch reducing coupling with the 4-inch opening outward. 22. A 3-inch to 2-inch reducing coupling With the 2-inch opening outward. 23. A four-way cross in horizontal position. 24. Same as 23, -except the downstream opening plugged. 25. Same as 23, except the upstream opening plugged. 26. Same as 23, except the streamward opening plugged. 27. Same as 23, except the downstream and streamward openings plugged. 28. Same as 23, except the upstream and streamward openings plugged. 29. Same as 23, except with a 12-inch nipple in the streamward opening. 30. Same as 23, except with a 12-inch capped nipple in the streamward opening. 31. Same as 23, except with a 12-inch open nipple in the streamward opening, the
downstream outlet plugged.
32. Same as 23, except with a 12-inch open nipple in the streamward opening, the
upstream outlet plugged.
33. Same as 23, except with a 12-inch capped nipple in the streamward opening,
the downstream outlet plugged.
34. Same as 23, except with a 12-inch capped nipple in the' streamward openlings
the upstream outlet plugged.

STANDARD PIPE WITHOUT FITTINGS
35. 1-inch pipe with end cut square. 36. 1%-inch pipe with end out square. 37. 2-inch pipe with end out square. 38. 2,4-inch pipe with end cut square. 39. 3-inch pipe with end cut square. 40. 4-inch pipe with end cut square. 41. 6-inch pipe with end out square.







INTAKES FOR GAGE WELLS 41

42. 3-inch pipe with end out at an angle of 10', and placed so that opening faced
10' upstream.
43. Same as 42, except with angle of 20'. 44. Same as 42, except with angle of 30'. 45. Same as 42, except with angle of 45".

OTHER DEVICES
46. Kinnison intake box. A short airplane wing section set at a 6' negative
angle of attack with the intake on the under side at the point of zero pressure. 47. Circular plate, 6 inches in diameter, with a 3-inch opening in center of plate. 48. f8amb as 47, except 12 inches in diameter. 49. Same as 47, except,18 inches in diameter. 50. Rectangular plate, 12 by 24 inches, with longer dimension horizontal, 3-inch
intake at center.
51. Same as 50, except intake 6 inches downstream from center of plate. 52. Same as 51, except intake 6 inches upstream from center of plate. 53. Eisenlohr intake box. A casting resembling a 3-inch pipe compressed to a
stream-line shape with a %-inch by 15-inch intake slot on under side.
54. Palm funnel. A truncated right circular cone; large end 12 inches in diameter,
pointing outward. Elements of cone form an angle of 40" with common
axis of cone and pipe.
55. Sawyer sieve. A 3-inch pipe with end cut square; four rings of four holes
Y4 inch in diameter; rings spaced 3 inches apart; holes to be as far from the
open end of the pipe as practicable.
56. Concrete pier, 12 inches high and 24 inches long; intake near top at center of
pier.
57. Same as 56, except with the top of the pier beveled downward at the upstream
and downstream ends.
58. Standard 3-inch tee with outlet on the pipe; flow through the run. 59.1 Same as 58, except with a 12-inch nipple in each run. 00. Same as 58, except with a 12-inch nipple in the downstream run. 61. Same as 58, except with a 12-inch nipple in the upstream run. 62. Same as 58, with threads removed from the run. 63. Handrail tee with outlet on the pipe; flow through the run; threads removed
from the run.
64. Same as 58, except with the run in a vertical position. 65. Long static tube of 3-inch pipe with cap on upstream end and connected to
intake pipe by elbow at downstream end. Two rows of Y4-inch holes arranged with 8 holes each on top and bottom, holes beginning 3 pipe diameters from upstream end and ending 3 pipe diameters above down
stream end. Tube pointing upstream.
66. Hanlon funnel. A cylinder 9 inches in diameter and 5% inches long with a
conical section on downstream end 4 inches long with downstream opening 6 inches in diameter; made of sheet metal. Side of cylinder attached to
the intake pipe.
67. Twitchell baffle. A horizontal and a vertical vane of %-inch sheet metal
inserted in end of pipe, protruding 6 inches. Replaced by No. 72. 6& Same as 67 except vanes turned 45* from the vertical. 69. Frior intake. T wo. intake pipes with the intake on one pipe turned upstream
: and the intake on the other pipe turned downstream.
7G. Canfield. baffle. A Ast plate 8 inches square, normal to current, held in
position 3 inches upstream from end of pipe.

M996"I ---- 2






42 MMIUODS AND EQUIPNMNT USED- IN STREAm AGING

71. Same as 70, except with the plate held in position cjjl thwd &de ot
pipe.
72. Same as 67, except the vanes adjustable to protrude different distances fr m
the end of the pipe.
73. Same as 65, except pointing downstream. 74. Ash baffle. Same as 72 without the horizontal vane. 75. Cast-iron strainer, Walworth catalog No. 88, figure 2270. 76. Same as 75, except pointing downstream. 77. Curtis sleeve. A 12-inch cylinder, 18 inches long and concentric with the
intake pipe, with the end of the pipe at the center of the cylinder.
78. Twitchell sleeve. A sleeve 12 inches long concentric with the intake pipe,
the end of the pipe at center of the sleeve. The sleeve 6 inches in diameter where it projects beyond the pipe, increasing to 7.4 inches: in, dialfiaer
at the end of the sleeve that encircles the pipe.
79. Short static tube of 3-inch pipe 14 inches long; end of tube closed by a plugged
coupling; downstream end connected io pipe by an elbow. Two rows of eight holes, one row on top and one row on bottom of tube. Holes Y4 inch
in diameter and spaced 1% inches. Tube pointed upstream. 80. Same as 79, except normal to flow. 81. Same as 79, except elbow replaced by a standard tee with outlet on pipe and
capped nipple in downstream run.
82. Same as 81, except nipple inserted between the static tube and the tee, with a
vertical support to bed of stream at the downstream end of the static tube. 83. Same as 79, except tube pointing downstream. 84. Same as 81, except tube pointing downstream. 85. Rectangular plate 12 inches wide by 8 feet long; intake at center of -plate. 86. Same as 85, except plate 6 feet long. 87. Same as 85, except plat& 4 feet long. 88. Rectangular plate, 24 inches long, extending from 6 inches above the intake
to the bed of the stream.
89. Static tube 9% inches long, with four rings of Y4-inch holes, rings spaced 1%
inches apart, four holes in each ring. Holes staggered in alternate rings.
Tube pointing downstream.
90. Static tube 18 inches long, with five rings of Yc-inch holes, rings spaced 1%
inches apart, tw'o holes in each ring. Holes staggered in alternate rings.
Tube pointing downstream.
91. Static tube, 18 inches long, with six rings of %6-inch holes, rings spaced 1%
inches apart, six holes in each ring. Holes staggered in alternate ring&
Tube pointing downstream.

METHODS OF TESTS

With the large number of devices to be tested in the laboratory it was desirable that some method be used that did not require too much time for the testing of each device. It was therefore decided to do as much preliminary work as possible with small-scale models, and so far as possible to use models for which the proper-size pipe fittinp would be readily available. A 1: 8 ratio was selected as being adapted for use in the small flume, 10 inches wide, in the laboratory. Prior to the selection of this ratio it had been decided to use a 3-inch M'take pipe as the full-size prototype for the standard of comparison. The






-r-NTAKES FOR GAGE WELLS 43

%-scale models,, therefore, were made for intake pipes % inch in diameter. Thew models were mounted in a glasssided flume 10 inches wide in such a manner that the effects of horizontal angles and vertical JE: angglea in the plane of the current could be studied. The intake devices were connected to a Y8-scale model well by the Y8-scale intake pipe. A standard static opening in the floor of the flume directly under the intake was connected to one of two glass manometer wells placed side by side. The other glass manometer was connected to the bottom of the model well. This arrangement was very effective in showing" the -am unt -of draw-down as indieated by the Aifference in the water levels in the two glass manometer wells. The heights of the water surfaces in the manometer wells were measured by a doOW-poi-nt gage having a point in each well. This was found to be 'N. more accurate than to make a direct reading of the height of the
water surface in the flume with a point gage.
After the preliminary arrangements were completed and the Yssc le ) model in readiness for the tests, the members of the laboratory '47 committee tested all the A models for a velocity of 2.8 feet per second
pIMM9 the intake, the velocity being measured by a pygmy current M. meter. This method of procedure provided a ready means of comparing the performances of the various intake devices.
Suggestions for eliminating draw-down have generally fallen into,
one of three g oups--(1) reducing velocity and thereby reducing the draw-dow-n :(2) using part of the velocity head to overcome the draw-down; and (3) straijhtening the flow to eliminate the effect of velocity. Tests of the A models showed that most of the devices for which the draw-down was less than half the velocity head were in the group that straightens the flow, and few of the other devices appeaxed
to eliminate the draw-down to that extent.

LABORATORY EQUIPMENT FOR TESTS OF 1/8-SCALE MODELS

The small glass-sided flume shown in plate 28, A, had been narrowed
from a width of 20 inches to a width of 10 inches by a longitudinal Partition. This small flume was 35 feet long, and the models were tested about 13 feet upstream from the lower end of the flume. As it I. was desired to have the arrangement correspond to field conditions as
nearly :as possible, and the models to be tested were %-scale, a model
ing well 7% inches square was installed in the unused portion
vtthe flume. This model of a stilling well 5 feet square was connected to the working half of the flume by a model of a 3-mich intake pipe consisting of X6 *inch outside-diameter copper tubing.
The outer end of this tubing was connected by a short length of rubber




44 MTOSAN QIX;TUf..M






tuigad ipe oterero *bh ra:0pin *ot
by amouningbloc sothatitscentr ws. 2B ichesato*6iteiO ofitiefiumeind itsfront % inces outfrom -heiwsU of ihiftie
Theiiiiiiiiiiiiiiiii moesw r hnsre e notefotoftic pig T e
couiiiiiiiiiii iiiiiiiiiii sode e to thiiiiie d ofaiiiiiiiiin h a p p

arei iiiiii iiii pl t 2 ,B
Gls iiiiiiiiiiiii mounted sieiiiiiiiih o tsdew f h flumeii asshwiiilaei9iAadiweeiraneiiiiinetont
modelsiiiiiiriousipostions.i'Thimaiometer wells. iiiiiiiiiniii

amtra.h.et.ftesre.f aoees ee sdm bann
coprtv egt fwtri hemdlwl n n:tefuea
th nae h etoeo h mnmtr a once oih
boto of th tligwel h ihthn aoetrc e
conete toi iiiiiiiiiiiiiiii one of seea tn adsai oeig n h l o

aln th etrln o h okn ar ftefue, noini i
thiiescina teculn uprtdb h onm
ben sd xetfrtoedvcswihb hi omo osrc
tion.......... inefrdwt|h ttcwtrpesr tta on rcn


vee h ae notesiln el rmadfeetscino h
flm.Teeoeig eeaot01 otaatna h nae
The poiin ofte ae sracsi te womnoee wW
mesrdb obepitgg aigapitoeaig i.ec
....... Th hegt ftewtrsraei h t e" ntolilu

welcudas emaue ietl yapitgg one v.
moal rm htsandtesdso h lm.Hwvr.h flcutosi h ae ufc i h lm aei ifatt
obai acuaeraig yti eho.Temxm aaiyo

th@lm a bot17 eodfet h lwwa esrdb
retnulrwiri hertrncane nerteflm.ThsWI ha be fll albatd o peios rjetsm teflmead a

not ecaibrtedforthi wok. he eloity'intheflueiaith i
taewsmauedwt ym cretmtr
THE- AODL








GEOLOGICAL SURVEY WATER-SUPPLY PAPER 868 PLATE 28


































le4"VV
A. FLUME USED IN TESTS OF THE A MODELS.



















j4



















B. MODEL GAGE WELL, MOUNTING BLOCK, AND SUPPORT, WITH MODEL A-39 POSITION FOR TEST. Static openings in floor of flume.








GEOLOGICAL SURVEY WATER-SUPPLY PAPER 868 PLATE 29































-7W



A. DRAW-DOWN IN MANOMETER WELLS UNDER THE POINT GAGES IN TEST OF MODEL A-39.





































B. TESTS OF MODEL A-79 UNDER A VELOCITY OF 2.8 FEET PER SECOND.
Manometer wells indicate practically no draw-down in this test. .......... .......






M AIMS FOR GAIIE'WELLS 45

T A inm 2.-Dimensions. of skindard sizes of pipe

Actual diameter (inches)
Nominal di-,
ameter
(inches)
Inside Outside

0.269 0.405
.364 .540
-493 -07
-A22
.824 1.050
1 1.049 1.315,
2. 2.067 2.375
2M 2.469 2.875
3 3.068 3.500
4 4.026 4.500

t" outilde-W=eter copper tubing that was used in some of the connections had and X0 %= i 0. inck.

1AA4M1MLthMV-fiM. of the table of dimensions of standard sizes of pipe
'the diameter of the Y4-inch pipe is very nearly,
on64*0" AAaimide diameter of the 3-inch pipe. Therefore Yi-inch, bram V Vewas generaHy used for the models, although the outside dia=obo,,,,did,,no*,,.:Correspond to the scale'ratio. Standard fittings wem Wed -whom U"ded. These fittings did not have the correct 'Jor tb*:.scale ratio, but their shape was made to coltopmd; to Ith" Of.. liha prototype.
T 7movtX4eW6 models were made for nearly all the devices that heA, k"o4lauigg"ted by the district engineers. A few devices were of such "pe that %-acale models could not -be made conveniently, and texWotAAw deviom were made with full-size "P" models without th& tests. at X-scale. A list of the A models actually
tested &eir dimensions is given in. the following table:
;r
T&BLIC 3. Dimensions of A models

A-3,S t# True to scale.
7
Y44neh pipeY4-inch pipe fittings, outside shaped to form of prototype. All Y4-inch pipe fittings except that tee and nipple cap A-1 ------ had outside shaped to form of prototype.
A- Y47inch pipe fittings, outside shaped to form of prototype.
A- -------- AD %-inch pipe fittings except that the cross and the
nipple cap had outside shaped to form of prototype. r rue to scale, connected by Yk-inch pipe. True to scale, connected by Y4-inch pipe.
-7 - - - - %-inch pipe 2Y4 inches long with four rings of Y42-inch
holes, four holes in each ring. Y4-inch tee, outaWshaped to form of prototype.
-------- Y4-inch pipe and: fittings, outside of cap shaped to form of prototype.
A-M *,,;&-67 --------- True to scale, on Y4-inch pipe.
----------------- True to scale, on %-inch pipe.
A-72v A-74, A-77 True to scale, on Yt-inch pipe.






46 MZTHODS AND EQUIPMXNT USED IN 'STREAM AGING

TABLE 3.-Dimen8ions of A modeU-Continued
Model No.
A-78v A-83 ----------- %-inch pipe and fittings. Pipe capped instead of having
plugged coupling, but cap is very close to male model of coupling, as it is made of stamped metal instead of being cast.
A-85 to A-88 --------- True to scale, Y4-inch pipe connections.
All the models listed above were- tested in the normal position and 4 i" 0 A 10' in both
in addition they were usually teii6d. at angles f 5' an directions from the normal position in either a horizontal plane or a vertical plane or both in the direction of flow. Some models were also tested at'horizontal angles of 15' and 20*.
All the models were tested under the same velocity of 2.8 feet per second. In table 4, which shows the results of the tests, the models are listed in the order of best performance in the normal position. Dnly the most favorable observation is shown where more than one
-observation was made. The performance of some models in the
-normal position gives them a more favorable position in the list than is warranted by their performance under conditions of angulaxity. Prom a study of those tests 17 models were selected for further M'vestigation at velocities of 1.0, 2.0, and 3.65 feet per second. Model A-39, a 3-inch pipe cut square, was also included for comparison. The results of the tests of the selected A models under the various velocities are given in table 5. The depth of water in the flume vaxied between
0.55 and 0.65 foot.
The velocity at tU intake for each setting of the, flow in the flume was measured with a cup-type pygmy current -meter that had proviously been rated in the current-meter rating flume of the National Bureau of Standards. The meter could not be placed exactly at the intakeowing to the pipe connections, but was used 0.25 foot upstream from the center of the intake.
The static opening at the mounting block was used for all models except A-65, A-731 A-791 A-832 and A-88. For models A-65 and A-79 the opening 0.17 foot upstream was used, and for A-73 and A-83 thecopenin-a 0.17 foot downstream was used. As mo&1 A,-88 extended to the floor of the flumeno static opening in the immediate vicinity of the model could be accepted as giving a true indication of the height of water in the. flume. Therefore a static opening about 8 inches upstream was used. As this model filled a large portion of the cross section when it was turned to the usual horizontal angles, the results obtained under those conditions may not have been truly representative of its performance in a natural channel.













INTAES FR GAE WELS 4

1,- 1 1"" .1 = 1 1:"-, 5 0










0




f f







ZD~~ 9 19 t ID91




IVI


9 9 cc 1



as $4 1I f





1= C" II ID 1=:9 99!c
+I


Cq q o D w M dow ) 0 lt 9 -34: ( I




CDI









































A R 5I 3* I I
METHODS ~ ~ I II QIMETUE IN ITA GAIN


:ao s
C!I


+l a e 1 t b t i
g g y ( M I I d M t t $ A









as Cc- c g 11 1 II11 Al







4i t N

0I4i


l9t i p I
1 1aE r















I a I I I

'S








I~ I t II












ITII








I4Ia toI f tr I


I 1 5 1 10 1 0
I I. I 06 1 t

S I r k

:S:.;- A. 8, 8

























cc V-4



















44 -44-4 r- -4- .


































1-- -4 4C4 Cl C' 1- <4q
















444 LI C4a.k 4a I



























10 t







toh








I I











C4 I-I c

LID(

E-4

toit

P4 c c-4g 4 a

E-44

d I












I tt














)oil
IC*
4 C4C i





























C>O

1-4 o CA m 1
C13 C C)


cq 0 A -1 to o .
C) C -4 D C
C) 8 88 c- 4 8 D C C>C= D C

-4 -4
cq k CD eq -.) D C)8 8




II t





0000


.,0: Ch O eq~~~ 0000 4 00






O 0000




-15

8 888M
i~ t I 4 l





I Al l
I0


o wc o
r8 84 m
I ?II











52 aMmoDs ANiD agelPMRl* USN1 aA G~stAGINGe


















t". cc cog ab co* S

a5 I C58 AC> a

C) co "4 *4 C>s. s
-. M 8




c t & 4= B t I 8
"S A
4 t A b4 8
I 5 A A I8 I
+







a 01 1 5 I' I' f C5 ICDI9"
F, (D 1Q ca t: 5 5 I A





9 g 8 4AA Aig





8~ ~~~~~ k 1 9sIe1












2: ag) .6 A C4 $ 513



































8, I T 4 !31t13 8 $







5 4 I 8 8 5 I:0t-04 11t P
$ ) ) 8 ~IS1 88 4 $ 35 I 4 & ( I I t 1 I 1 I C5



8 5 A 8 I 4 03 ,4 I 1 a 9
1~~~~~~~ IC4 9g(44 :- -RV I 4t t 4 3I






11 8 CC t U139 goiC t
t~~~~~ C IIt 4 C) C)I1
CD 1I I f9 * 6 0

bl m I0 C% 1 eq -4 00 to gI













I o4 ac :tM


C;O
e5 I-a m c C mo N -o emr em
8o8 8808 800 8000


C4l m cco' 00 M

I~~t 111 ftil tt I8 I 0 1 IC) I 3 I I


I l l 1 L i t-1 E l









1 F






$11 II~t4II




t i lI F1 9 1 1 tz
t i l ~i l i e s t e t .. 1




iii54-iii 3iiiiiiii ANDiiii~ii iiUYAif US D:INiiiM GA IN
HN~i~HNHi~N~iiiliiFULL-SIZEi MODELSiNI@@iiiii
Th 7fl-sz oes htwr slce ortssae itdo
pagesi6-58.The EiiiiiiiboxinditheialwiiiistaineriLre::ieste at full izewtotpeiu et n1 cl oes stercn
iiiiiiiiiistiiruiiiic tiiiiiiiiiio n. ........................d n.............................
1:8ii scale.iiiiiiiiiiiiii Thiulsie m d lsoihiiic sfo s 1*h 3i
iiiiiiiintakeiiipipesiiisometimesiiicallediiitheii"prototypes,"iiiiiwereiiigiveniitheiisiame iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii i a numbersiiiiiii asihe cor es on ing mo eliat thi1:8iatoibtier iiiiiiiiiiiiiiiidiii i stinguishediiifromiithe small modelsiiibyitheiiuseiofithe prefixiiiPithe ...............................................................................................t heiiis m a llii
imodels
FullH-sHizemdesofdvce orue ihvaiussze finae ie
Nwer giiive the following desig.........
iiiiiiiiiiiiiHiiim odelsiiiiforiiiii iiiiiiip ip e.i i
Kmoel or1%ichpie
L,~ modelsiforiiiiii pipe
Mmoes o 22inhpie P, modeliforiiiiii pipe
iiiiii ~~Q iiiiiii iiiiiiiii iiii h pip e....................
"PR U USE INTETiiiiiiUL-IE ODL
In ore omkiet ftefl-iz oesudr eoiista
would be comparable with those obtained in the 10-inch flume in the
tests of.t.e.A.m.dels,.a.t.mporary.t.m.e..f.ume.3.f.et.i.....th...
cosrcedi h cne f h 2fotfue.(e pl 0 .
Ths3fo luews4 ee nlnt adwsoe a ohedi
Theiiiiiiiiii sides atteupriiieecuvdotad ofr bl-hpd
enrncwhc xtned4 ice usrembeodth trih
part of the 3-foot flume. A 14 inch o ening between the upper end
of the bell-shaped entrance and the side wall of the 12-foot flume on
iiiiia c h iiidei a d it e w a e toii the....................................................
12fo lm. hs ue 45fo pce eecoedb eprr
buked post h oe edo h -fo lma soni lt
30 .Udrtisarneetsatcwtrpesrewsmitie
o n eotieo h -otfue ltog l h lwwscridb
tba lm.Tehegto ae n h lm a onrle ynel
gatesiiii 25 fetdwsra.Tes edegtswrests st an
; ;t a......... ...........................................................
Th xathegtofwte n h luewaieaue b easo
pieom e gages.o..sie.th...lume.a.l.co..eced..o.st.ti..pening...
th.loro.tefum.Te.ttc.pnng.oldas.b.eartl .....................................................................
meters and the gage well are shown in plate 30, B. Static openingi No. =Ii wsinihecetr f heflm2fetiowstemiro te n
taecnncin sai peigN. a i h ene fth lm









'An intake.pipe.3.inches.in.diaete..pa.sed.through.the.sidew ll
th.3fot lmean ws lce s tatte evceune tstwhni i
h oriohal ostin wul b inth' entr f he lue nd fetav
itK loer end The oter en of te 3-inh intae pipewas connect to the outlet..... ofiiii a 3-inch tee, which iii turn was screwed to the top of a~ii~ii~ii~~i~~i~iiiiii~i~~i 3-inc riser pie but.was..............for.o.tining.horizonta an le
by means of a, %7nch pipe handle onnected to theiop run of the te
by eas f eduer. hepie hnde asexendd o n peing
in the wall of the 12-foot iifilu'me, so that We settings. iiiiiiiiiiiiiforthe various iiii~ii~i


tur mling the intake pip in the" tee connection the angle of tilt bein
indicated bya ontr
Yro te isr ip a te ute ed f he3-nc itae ipe 1-inch ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~"i pip concin.....h aesiligwllue ortecn nection to thestatic penings.Valvesin.I.eah.line .ermitte ii






6 MZT]RODS ANID EQUIPMENT USMD IN 13TUAM AGING

W6ter surf~




a5
.......... .. ...... s P 1P.,P.1po., 4X 12


10
1.0
W



1.5 Intake
0
X

(L
Lj 2.0

C14

Z5




3,0
0 05 1.0 1.5 2.0 Z5 3.0
DISTANCE FROM LEFT SIDE WALL$ IN FEET
FiGuRic 4.-Distribution of velocity in the Moot flume for a velocity of 2.8 feet per second at the inbjm

MODELS SELECTED FOR TESTS

The models selected for the full-size tests corresponded to those which gave good results under the tests of %-scale A models M'J the 10-ineb flume. A few full-size models were tested without previoul; tests having been made at the %-scale. Tests of intakes pipe witb the ends cut square were made for purposes of comparison. The full-size models that were selected for tests are listed below.

TABLic 6.-Fulkixe models selected for testa Model No.
H-35 ---------------- 1-inch pipe with end cut squ&re.
K-36 ---------------- I J-inch pipe with end out square.
L-37 ----------------- 2-inch pipe witb end cut square.
M-38 ---------------- 2 j-inch pipe with end cut square.
P-39 ----------------- 3-inch pipe with end cut square.
- ----------------- 4-inch pipe with end cut square.






INTAKES FOR GAGE WELLS 57

TABLE 6.-Full-size models selected for tests-Continued Model No.
P-46 ------------------ Kinnison box with 6-inch nipple and cap at outer end.
M -49a -------------- Circular plate, 16 inches in diameter, attached to 2Y2-inch
intake.
P-49a ---------------- Circular plate, 16 inches in diameter, attached to 3-inch
intake.
FL-5o ---------------- 12- by 24- by 34,5-inch steel plate, long dimension horiZon.tal, intake at center.
-53 Aubr box, 6 by 20 inches, stream-lined, intake slot
---------------- Eiseh
half an inch by 15 inches.
L-58y M-58p P-58- Stock tees, outlet on intake pipe, flow through run.
L-58a, M-58a, P-58a- Stock tees, same as above except that threads were removed from run to make it of uniform diameter. L-58b --------------- Handrail tee, threads removed from run.
L-721 M-729 P-721 Twitchell baffle, vertical and horizontal vanes one-eighth
Q-72. of an ineb thick held in position in models L-37, M-38,
P-39, and Q-40, respectively, by set screws near outer end. Lengths as shown in table 8. Ir-441 M-741 P-741 Ash baffle, vertical vane one-eighth of an inch thick held
'( 74. in position in models L-37, M-38, P-39, and Q-40.
Lengths as shown in table 8. P-75 ---------------- Walworth cast-iron strainer, catalog No. 88, pointing
straight out, normal to direction of flow. P-76 ---------------- Walworth cast-iron strainer, same as P-705 except pointing
downstream.
L 79 ---------------- Static tube, 2 inches in diameter, 14 inches long, eight
holes half an inch in diameter spaced 1% inches apart
4
top and bottom. Tube pointing upstream. M-7 --------------- Static tube, 2% inches in diameter, 17Y2 inches long, eight
holes five-eighths of an inch in diameter spaced I% inches apart top and bottom. Tube pointing upstream. P-79 ---------------- Static tube, 3 inches in diameter, 13V4 inches long, eight
holes three-quarters of an inch in diameter spaced 1% inches apart top and -bottom. Tube pointing upstream. P- W__ ------- ------- Static tube, same as P-79 except pointing straight out;
normal to direction of flow.
L-83) M--.83v R-93---- Static tubes, same as L-79, M-79, and P-79 except Pointing downstream.
------------------ Steelplate, -some as P-50 except that another 12- by 24by %g-lnch plate was attached below P-50 so that the total height was 24 inches. Intake in center of upper plate.
P- 8.9 ---------------- Static tube, 3 inches in diameter, 9Y2 inches long, four
rings *of four holes three-quarters of an inch in diameter, rings spaced three-quarters of an inch apart. P-90 ---------------- Static tube, 3 inches in diameter, 18Y4 inches long, five
rings of two holes three-quarters of an inch in diameter, rings spaced 1,1t inches apart.
---------------- Static tube, 3 inches in diameter, 18Y8 inches long, six
rings of six holes nine-sixteenths of an inch in diameter, ringa spaced I Y8 inches apart.






J.
58 METHODS AND EQUIPMENT USED IN 'STUEAM AGING

TABLE 6.-Full-sixe models 8elected for testr-Continued N
P-92 ---------------- Static tube, 3 inches in diameter, 18Y4 inches long five 5
rings of six holes nine-sixteenths of an inch in Aftm, A eter, rings spaced 1% inches apart.
P-93 ---------------- Static tube, 3 inches in diameter, 19 inches long, -five
rings of four holes three-quarters of an inch in diameter, rings spaced 1% inches apart.
P-94 ---------------- Static tube, 3 inches in diameter, 13 inches long, five
rings of four holes three-quarters of an inch in d1am_' eter, hiring spaced I inch apart.
P-95 ---------------- Static tube, 3 inches in diameter, 12,4 inches longf outer
end closed by plug with hemispherical nose instead.of standard coupling and plug; arrangement of holes game as in P-94.
P-96 ---------------- Static tube, same as P-93 except that length of tubei
between couplings was 18 inches.
P-97 ---------------- Static tube, same as P-94 except that length of tube
between couplings was 12 inches.
P-98 ---------------- Static tube, same as P-95 except that length of tube was
12 inches.
L-99 ---------------- Static tube, 2 inches in diameter, 12 inches long, 5
rings of 4 holes % inch in diameter, rings spaced I inch apart.

TESTS

In the tests of the full-size models each device that was to be tested was attached to the outer end of the intake pipe by means of a coupling, or a coupling and elbow, so that the intake opening would be in the center of the 3-foot flume, or as nearly in the center as it could be placed. The models were all tested in a level position, with the device, pointing in the direction in which it was intended to be used. in addition to the tests of the models in the normal position, tests were also made with the models turned through horizontal angles of +5* +1009 50 and 10' and for similar vertical angles. The hori-. zontal angles were designated "plus" for a movement in the clockwise direction from the position in which the intake was intended to be; used, and "minus" for a counterclockwise movement. Vertical angles were designated "plus" if the movement was upward from the normal position and "minus" if downward. The effects of angularity were studied in order to obtain information regarding the relative performance of the various devices if the direction of flow was at, an angle with the mitake.
All the models were tested for the' same velocity of water in the 0.M
flume, which was 2.8 feet per second immediately in front of the. intake when the mean velocity in the flume was 3.0 feet per second. (See fig. 4.) The corresponding discharge was 27 second-feet, which






IINTAX S FOR GAGE WELLS 59

was as much as could be obtained for continuous use, from the pumps that wereavailable.
Static opening No. 2, immediately under the intake, was generally used in the determination of the height of water in the flume, but for the static tubes pointing downstream the average of heights for
openings Nos. 1 and, 2 was used, and for static tubes pointing upstream the average for openings Nos. 2 and 3 was used, as for these positions of the static tubes the openings in the tubes were between the two static openings in the flume.
A considerable number of the models that gave favorable results under the tests at 2.8 feet per second were subsequently tested for a velocity of 2.0 feet per second. The results of the tests for both of these velocities are given in table 7.
A comparison of the results of the tests of full-size models of devices for use with different sizes of pipe, including the sta tic tubes the Ash and Twichell baffles, the circular plate, the tee connections, and the straight pipe with end cut square, axe given in table 8. The tests shown in this table were all for the same velocity of 2.8 feet per second. The correct lengths of the Ash and Twichell baffles for use with different sizes of pipes were determined by experiment. The results of the experimental tests for determining the correct len ths are given in table 9.





































tit itt












I l l




1 'F I'

9 ~ ~ 4 -4 40 0 "zM mrq1 Y oI tit 00










cc m a ccoao




























1 C! CA












CIOI




Q) 0 a o oo
*M
iCRiivi ciiiii
CiiiiCi iiiiiiii iCi'ii
9 9iiiiiiiiiil~iiii~ii, oiii i~iii~iiiiii~ ii i

C )i iiiiiiiiii iiiiiiiiiiiiiiii ii iiii i
cli ci cii iiiiC4iC4iii &AiC4iC4 C4iiiiC4 ci C4 @
0,,HH i n



(Dii~ ii iiiiii iiiii~ iiiiiiiii~ iii
onii i iiiiiii i iiiiiiiii i i
O Dii i i i i i i i i i i i i i i i i i i i i i . ............... .............. . ................................ ..
Ran

iii caii 0 ,0iiiiiii iiiiiiiii b'041ii
i4i1Ziiiiiiii -0i
goi~ i i

C) O = riiiiiiii:3iiiiii i
A iiiA iiiili"HiHiiiiiiiiii Hiiiiiiiiii 0i~
CODii 4.

4--i 4 .iiiiiii iiii iiiiiii

ii iiii iiii iiiii
.$ 4
iii i iii ii ii
ii.. 4-D 1iiii
P.......... .......... 9 1,,,,,= iiiiiiiili
ccii iiiiiiiii

























:aa eo o Is :ass : : 1











IIt II.

-Ap$



ts~






0 CI

Co t8 Q5 <1:1 1=ow lot' c e

tit g -n-o -g-m




+ It



I I f 5 II f f f fl l





0000



























Iq i I I






CD 00 eq
"SI



lam~I -1 :0 G
:I C' CDI




+A I








eq"Rp C C,-qt mC qtoC c -t :
41, D C Ci : C C> D C



(M4 (D ,Cp ) C ,C DC




















C',1 11 1

C4 C# CD t l
CDl~
CIt . ItC






C', I0
cq Cq C,


C5l







CD wwwwww


































to 9 I 4
4~~~~- W" 9- "0 4 ea a












gle III t s t4
mi~C C! C! 10.'


f i t t i-3R 49 8







I I I I





c5l










C13<
) ~~~' ata g g ga a .. ** .














40 g
V V -.
8*I1s8assss- Ig Iao5~~~~I f I I .el 9 9 9 $ 9

COatho eaa00 so
-4 IVgow...ww....w..www.. w=.e C QW WM WWe0s000000

.6 iC iwpus- 4C 4C ic C R0 i0 C 4O 4O 4c C iC 4C 4C

0asssses0n


-aancc
e> asssssn



cc
1 4 ma b DI o C o g C C 2 I a w A 4 i w : w = D Mv


04 0 9 c cota lico" 'ti l -t C C2C t l! 4 0R t





to .t. .it












.1 Itt i I


I.i lIi I

4 1p4 I I 1 11 I. I


Iste






stit11

40 1F w 4p 4p I qv RI RO g g x g g











INTAKES FOR GAGE WELLS 65
















I A t
UD





I t I f 4 1 1 1
























I t


go 00 00 to 00 00 00 co Go 00 00 ao Go c,4 cq cq c% c4 oi A A 0 ci c4 c4 ci





c' -,* c, ,a n c' C.
c4 ci A C4 C6 cli C4 C6 CIS cl C-i 0i Lo
41.1 &CLIO== 00100C mlkf 0 CIS 4 1 6 4 kd Cd 16 Ad C6 %6 te te tl:




Cq 04 eq 04 01 C14 m M'w r qw







METHODS AND EQUIPMENT USED IN STREAM AGING

COLLECTION OF DEBRIS ON INTAKE

The relation ordinarily existing between the heights of water in the river channel and in the stilling well where the records of stages are obtained may be changed if debris becomes lodged or collects .. at the end of the intake pipe in such a manner as to interfere with the free movement of the water into and out of the gage well. In order to obtain some information regarding the effects of debris. on- the p6rfoiiiiince'of intake 6vices, thi6, collection "0' f debris in the Moot fluifi6 was simulated by means of an ordinary cement sack which was placed in the flume and allowed to drift down with the current until it came into contact with the end of the intake pipe and piLrdy covered the intake device. The results obtained are shown in table 10 and should be considered as being qualitative rather than quantitative, as the conditions of the experiments could not be exactly duplicated for the various intake devices.

TABLE 10.-Effects of collection of debris on intake

Difference in elevation,
in feet, of water surIntake iace in well from that
in ame

Without
NO. Description With sack Sack

P-74 Ash BaMe:
Sack covering pipe and one-half of baffle ----------------------------- -0.090 0
Sack cover!ng p!pe and baffle ---------------------------------------- -.110 0
Sack covering pipe and baffle and draped around end of baffle ------- 0815 0
P--89 Short static tube with ring of holes. pointing downstream -------------- -.055 -.002
P-79 Static tube with holes top and bottom, pointing upstream -------------- -.036 ON
P-83 Static tube with holes top and bottom. pointing downstream ------------ -.065 ON
P-53 Eisenlohr box:
All but inner 6 inches of box covered -------------------------------- -.073 -.006
All but inner 12 inches of box covered ------------------------------- -.057 0D6
Outer 6 inches of box covered ---------------------------------------- -.045 -.006
P-50 Flat plate 12 by 24 inches:
Sack caught on upstream end with ends over top and bottom of
plate --------------------------------------------------------------- -.016 -.006
Sack hooked cn upstream end with part on back and rest covering
face of plate -------------------------------------------------------- --ow -.006
P-76 Walworth strainer pointed downBtream --------------------------------- -.053 -.019
P-49 Circular plate ------------------------------------------------------------ -.044 -.01.0
P-46 Kinnison box ------------------------------------------------------------ -.00 -.014


REMOVAL OF SILT BY FLUSHING

The ease and completeness with which the devices attached to intake pipes may be cleaned and accumulations of silt removed from the intakes by the flushing apparatus usually installed in gage structures is an important consideration in the selection of the design. Intakes having large openings might be expected to flush more readily than those having small openings, even though the number of the, small openings was large enough to give the swne total area. In order to






INTAKES FOR GAGE WELLS 67

obtain some information with respect to the ease of Hushing of various intake devices, particularly the different designs of static tubes, proR vision was made for experimental tests under conditions similar to
those existing at aging stations equipped with facilities for flushing
intake pipes.
FLUSHMG APPARATUS
A- #ical steel tai about 6 feet in diameter was ava 14ble as
source of water for the flushing tests. This tank was' 'provid4with glass manometer and had been calibrated so that the amount of water discharged from it could be determined from the manometer readings. The average head used in flushing was about 21 feet, the reductim in head during a test because of the -dxop of. the water level in the tank being only about 0.2 foot. The area of the cross section of the tank was such that a difference of 0.2 foot in the height of water
corresponded to a release of 43.6 gallons.
A 4-inch pipe line, which was reduced from an 8-inch pipe line 12
fe6t above the outlet, was connected to a quick-acting Valve. A 4-rinch to 3-inch reducing bushing on the outlet of the valve was connected to a 6-foot length of 3-inch pipe to which the various static tubes and other intake devices wereattached by means of a 90' elbow. In making the flushing tests, the intake devices were filled with-mft-mud or silt -and. then attached to the elbow of the, 3-ineb pipe. By observing the' time between the opening and closing of the quick-actingvalve and th-e-corrbsponding drop of the water in-'the tank, the discharge through the intake device, in gallons per second, was determined. Observations of the amounts of water discharged through the devices in equal intervals of time without the use of silt
were also made for purposes of comparison.
TESTS
The static tubes and other, devices. were flushed with clean water and
then filkd with mud and flushed again. The mud was a soft clay that woWA just start to fiowout of, the holes in the static-tubes under a head of about 1 foot. Each tube was completely filled with mud back to the elbow connection. In flushing out the mud, the quick-acting valve was opened for 15 seconds and then closed, the amount of water discharged during that period being considered a measure' of the c fficiency of the, de'vice under the flushing test. No mud remained in the tubes after flushing, except for a few small pieces between the last 4ples. and the plu gged end of the tube in some of the longer modeb;.
The 3-inch.pipe, corresponding to model No. P-39, was flushed with
water as a basis of comparison. The results of the tests are
shown in the follo table:












METHOSiANiEQUIMENTUSEDH4iiiiiiiAOIi

TABLEiIiIi-ilishiniteiisiofiintikeiicesiioriiiiiiiiii
iiiii" ~~~ ~ ~ ~ ~ ~ ~ ~ ~ Tb fille iw~ mad-i iiiiiiiiiiiii =iiiiiiiii
iiiiiiiiiiiiiiT u beiiiiiiiiiiiiiiii4Wiiiiiiia
.... .. .. .. .. .. .. ....... ........................................ ....... .......................... ii ii ii ii ii i ii ii ii ii i ii ii ii ii i
iiii iiii i ii = '=] ...... .................. ...........T im... ..
iiiiiiiiiiiiiiiii iii iiiiiiiiiiiiiiiiiiiis )
el Numberii andi sieo oe fopnns frds
iiiii iiiiiii ~ N o.iiiiiiiii .....................................
iiii iiiiiiiiiiiiiiiiiiiiiiiiiiiii~ iiiiiiiiiii
iiiiiiiiiiiiiiiiiili iiiiiiiiiiiiiiiiiiiiiiiiiiiiii
5 p er
iiii iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii
M fee iiaverage

iiead
i AV

P -9 En.utsu.e- -- --.- -- - ---.. .4. .
iii~iiiP-79iiiiiiholesi i inchiiiiniidiameteriiitop==and ................. .- -- -- -- --7.1 .53 L 0 4
Pi-iiiiiiii4iiii irii ng f4h ls i cin d a eer7 1795i::s .Ii:

Piiiiiiiingsiofiiiiilesiinchiiniiiameteriiiiiiiii4iii6Z 6.4.2.
P-9 6 ig f6hleMaic n imtr&9& 10.





P-92 5 rngs ofi holesieiinch nidiameer-- 7.57.4i9ia 0iRi&7

iiiiiiiiiiiiiioxi.i- - - - - - - - - - --ii. 5 - -- --i- - - - - ---P -9i5ri gsof4iole i ch in di metri8i7i.ii--i--ii--i i--i.


P 4 -- d -- - -- - -- - -- - 8 87 0& - -
P -9i-- --ioi- --- --- -- --- --- --- --- ---i8.i7.i& -- --Forite coditiniof"tubefilldiwihiiuVith intae deiceiasicmpleelyiWd wihiiiiiii ifi
Mu ol utsar ofo u f oe ne buta1fo ed A h n fie ~~n a &
mudiwasallireovedieceptifoiaifewlumpsietweenihe hols and heiclosdiendini9idi











GEOLOGICAL SURVEY WATER-SUPPLY PAPER 868 PLATE 30







Ra























A. OUTLET OF 3-FOOT FLUME. ............





























B. PIEZOMETER GAGES AND STILLTNG WELL FOR THE 3-FOOT FLUME.














GOoLOGICAL SURVEY WATER-SUPPLY PAPER 808 #,LATE 3t



























A. EISENLORR INTAKE BOX. B. KINNISON INTAKE BOX.






IN W19LLS
WTAK S FOR GAC 69

could be tested only in the one position, but the tesults were very satisfactory in that position with the flow parallel to the plate.
RECOMMENDATIONS' FOR DESIGNS
Simple des1gM that are readily obtainable without the nocessity of special castings or complicated machine work areL generally desirable
the performance of special designs appears to be more satisfactory. In the selection of the type of intake device to be used at a aging: station the effectiveness of the device should receive primary consideration. The case and completeness with which it may be cleanod by the flushing arrangement ordinarily used in flushing the intake pipe and the manner in which it may be affected by floating debris arie important factors in the operation of the station. In rivets where the water is deep and swift the insta,11ation or remo'val of an Mi take device may be expensive, and under these conditions the 6 'tial'cost of'the device may not be the controlling factor in its nu
selection.
STATIC TU13NO
The static tube appears to be the most satisfactory device for eliminating draw-down at intakes to gage wells, so far as could be determ in ed from the laboratory tests.
The statio-tube device may be made in various desigm and in any size corresponding to the size of the intake pipe with which it is to be used. Designs of static tubes showing dimensions and arrangements of Openings are illustrated in figure 5. The total area of the holes should be about 20 to 25 percent greater than the cross-section area of the i e,- in order that deposits of mud and silt may be effectively removed by fl of the intake. The laboratory test& indicated
that a suitable arrangement of openings to provide the required area for the 2-inch, 2g-iiaLch, and 3-inch pipes may be obtained by using .five rings of holes with four holes in each ring, the rings 1 inch apart .anct the holes staggered in alternate For the 4-inch pipe, six
.. 4:
..rmp with six holes each axe suggested.
For pipe diameters of 3 inches or less the not length of tube between shoulders of couplings should be not less than 12 inches, and the outer rings of holes should be not less than 4 inches from the shoulders of the coxiplings. Them dimensions correspond to those of static tubes tested in the laboratory. For pipes larger. than 3 inches in diameter it is probable that the minimum length of the tube should be about four times the diameter of the pipe. The outer end of the tube may be threaded for a standard pipe coupling and closed by means of a standard plug, or it may be closed by a plug specially fitted to the mide of the pipe. lUpreferred, a cap may be used instead of the COUP].ine and plug. The use of a special round-nose plug did not give






70 METHODS AN EQIPM NT USED IN REAM GAGING


B ....

QQ




ii i ...........*
Four inch holes per ring 2" na s peUse 2 -inch pipe and fitting.








5f In+ f0+11+--- 5 Four%54-frkh holes per riIng Use 2,K-inch pipe and.fittings. 2Y' ntak apipe




OOF
std1-A 4f 4..f -- is


Fou r ass-i ne he as per ri ng 1Use 3-inch, pipe and fittings. 3" Intake pipe







0O Omm

















Si c 4-inch hoes per ring
Use! 4-inch pipe and fittings. 4'I ntak 1e p i pe Note.- Edges of heles to be free of burrs but not rounded.
Tube to be fixed in a hoiOzontal position.

PM~uAR 5.-Design of state tubes fbr use with Shanh, Syd-nob 8-ineb, anid &-took intakebipmb






INTAKES FOR GAGE WELLK 71

result's materially-diff 6rent from those obtained with the standard f -st- fie tubes made
coupling and plug. The hydraulic performance, o a
in the lengths specified above was the same when the tubes were pointing upstream or downstream, but less difficulty because of submerged drift and debris may be expected if the tube is used pointing
downstream.
The static tube may be connected to the intake pipe by means of a
90' elbow or by a standard tee. If the intake pipe points upstream from an artificial control, the connection may be made as show-n in figure 6. The tube should be fixed securely in a horizontal position, and pfovvis'ion made so that it will not tilt downward by turning of the ou--viin under its own.weight or any additional weight that may be placed upon it. In using a standard tee connection the static tube should be attached to the leg of the tee, the run of the tee opposite the
well being closed with a plug
5
The static tube devices tested at the National Hydraulic Laboratory
were constructea *of so-called "wrought iron" pipe with threaded 'ends'.
for connection to standard pipe fittings. One end of the tube was connected to a standard pipe elbow. At the other end there was a sleeve coupling into which a standard plug was screwed for closing the end of the tube. The "length" of the tube was considered to be the distance along the tube between the protuberances of the coupling and the elbow; the, gross length of the tube,, including the -threaded ends, consists of the so-called "tube length" plus the distances to which the coupling and the elbow axe screwed on the pipe. It was the
intention to test such designs as could readil be constructed by pipe
fitters using materials that could be obtained at stores and shops dealing in ordinary pipe fittings. The holes were drilled straight through the tubes, any roughness or "burr" being smoothed off, but with no bevel or rounding of the efiges. The tubes were made long enough to extend beyond the disiurbance caused by the elbow and
the intake to the well..
The static tubes may be made of ordinary wrought-iron pipe 'and
pipe fittings, or of galvanized wrought-iron pipe. Other materials, such as brass, bronze, copper, or stainless steel, may be used if desired.
The first cost of tubes made of ordinary wrought-iron pipe, either P plain or galvanized is comparatively small, whereas the first cost of
tubes-made of other materials would be somewhat larger, and their P performance probably would be no better than that of the less expengive tubes if the latter were not &ffected by corrosion. However, if the effectiveness of the tubes made of so-called "wrought iron" pipe became finpaired by accumulations due to corrosion, the cost of their replacement in deep, swift water might be much greater than the first
cost of tubes made of noncorrosive material.







72 METHODS AWD EQUIFMXNT USZD iw mmm GAGnq(;



..........


































4-0
Lrj














4q on


CL 20
CL





Ix (3
4

U)






INTAKES FOR GAGE WELLS 73

BAFFLES

The Ash baffle and the Twitchell bafRe appear to give practically as good results as the static, tube where the direction of flow is at an angle of 90' to the intake, but are not as effective if the direction of flow is at an angle c6usiderably greater or Im than 90'.

,/Steel plate

Int

Eiake pipe
L L );8


"' End of pipe Fi I let weld
cut square to pipe
DIMENSIONS
Baffle to be of such width that it will fit snugly inside pipe. Length to be as shown in table-.
Nominal diameter Length of bafFle
Of pf L Baffle to be fixed in
2 43; vertical position
2); 5 normal to current.
3' 53
4! 6/4
FiGURE 7.-Dwign of Ash baffles for intake pipes of various sizes.

End of pipe
cut square Fi I let weld to pipe



Intake pipe
L L
2 7

I/I;Steel platesjoined by slottin$ eachnilate DIMENSIONS for half its len
Baffle plates to be of such width thatthey will fit snugly inside pipe. Length to be as shown in table.
Nominal diameter Length of baffle
of pie L
5 z Baffle to be fixed in
5 3X psition with plates
3 6 horizontal and verticaL
7
IFIGURE S.-Design of Twitchell baffles for intake pipes of various skes.

All the baffles were made of %-inch metal and projected out of the pipe a distance equal to half their length. The proper length of these baffles as determined by tests1for the various sizes of intake pipes (see table 9) are shown in figures 7 and 8.


























o o









I I 1




C
iIV .x I0 miin
iiiiiiii .... H H i iiii0
i iii
iiiiiEiii C..............
iiiiiiiiiiiiii'ii'ii' ii i~ iiiiiii





iiiiii iii ... ... .....
!i~iiiiiiiiii~iiiw iiii iiiii iiii0iiiiiiiiii iiiiiii i iii 4,4

iiiiiiiiiiiii HCc :
ilii iiii @i~i iiiiiiiiiiiii iiCT

@@ ~~~~~~~IViiiiiiiiiiiiii
iiiiiiiiiiiiiiii v iiiiiiiiiiiii i~~ iiiii
iiiiiiiii iiiiii iiiiiiiii iiiiiii
iiiiiiiiii i))i))ii @)))~i@






INTAKES FOR GAGE WELLS 75
OTHER DEVICES
Several of the other devices gave satisfactory results and deserve mention because of certain desirable features in the individual designs. In the Eisenlohr intake box (see pl. 31, A, and fig. 9) the center of grwvity:-of the device is in line with the axis of the intake pipe, and therefore there is no tendency for the device to turn from the position in which it is intended to be used. This device might be expected to receive considerable use except for the fact that it must be made from a special casting and requires machine-shop work in finishing. The Walworth strainer pointing downstream gave good results in the laboratory tests and, of course, can be readily purchased as a commercial product. The tests of the A models of flat plates -that were intended to simulate the effects of a concrete pier flush with the end of the intake pipe and the tests of the circular plate attached to the end of the pipe indicated that the use of a vertical pier or plate at a clockwise angle of 5' with the direction of flow was effective in materially reducing the, amount of draw-down. The merits of various other devices can be judged by reference to the tables showing their performance.


























The use of the subjoined mailing label to return this report will be official business, and no
postage stamps will be required





















UNITED STATES PENALTY FOR PRIVATE USE TO AVOID
PAYMENT OF POSTAGE, $300 DEPARTMENT OF THE INTERIOR
GEOLOGICAL SURVEY

OFFICIAL BUSINESS
This label can be used onlyfor returning official publications. The address must not be changed.




GEOLOGICAL SURVEY



WASHINGTON, D. Ce










umam ITWn