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to 22 500, 25 000, and 30 000 lb. per sq. in. Beyond this stage increased
knowledge was obtained of the stresses developed in locked coil cables
due to bending. The influence of frictional hysteresis on the modulus
of elasticity of the cable in bending was ascertained, so that the ques-
tion of the proper tension of a tramway track cable depends largely on
the condition of the particular tramway which is being designed.

If it is admitted that stress, due to bending, is developed in the
outermost wire of a track cable, it is consistent to assume that a cable
can be made to fail due to excessive bending only. It is well known
that, if sufficient direct stress is developed in the cable, it can be
pulled in two. Therefore, there is an economic tension to be applied
to the track cable which will develop a minimum combined stress
in the outermost wire due to direct load and bending.

Bending stress is developed in the track cable due to its support
of the loaded carrier. The measure of this bending is a cable curve.
The tangent of the intersection angle is equal to the weight of the load
divided by the horizontal component of the tension in the track cable.
If the loaded carriers are low in weight and the tension in the track


. Mr. cable is high, the intersection angle of the curve under the carrier
phen. will be small; that is, the curve will have a long radius, and the stress
developed in the outermost wire, due to bending, will be less than
that due to direct tension.

This is the fundamental criterion which should be considered in
designing aerial tramways, where it is desirable that a proper life of
track cable should be obtained, together with a minimum of inter-
ference due to improper elevation of tower saddles.

The spacing of the towers depends on the tension in the track
cables and the weight of the load supported. With a proper radius
for the saddle supporting the track cables, the spacing of the towers
depends on the economic construction height of these supports. The
farther apart the towers are, the greater must be their height in order
to balance the deflection and clearance required between the bottom
of the carrier and the ground surface. The longest span which the
American Steel and Wire Company has put in is 3 600 ft.

Tension stations may or may not be used, at the designer's option.
In fact, it is customary to control the change of position assumed by
the track cable when loaded and empty by erecting it as an anchored
span. It is well known that the product of deflection and tension at
any point on a suspended cable is constant. Accordingly, in anchored
spans, if the loading changes, the deflection tends to remain a con-
stant, due to the change in tension. If the cable were non-elastic
and symmetrically loaded, there would be no change in deflection
between the empty and loaded positions. In practice, there is a slight
change in these positions, due to the elastic properties of the cable.

The pronounced limitation of tramway location to a straight line
is no longer apropos, as present-day designers do not hesitate to handle
moderate angles on the tramway supports. In this manner angles of
considerable magnitude may be introduced into the alignment of the
tramway without interfering seriously with its operation; nor is it
necessary in cases of this sort to build a special structure called an
"angle station."

Although the discussion has not been extensive, it has served a
useful purpose in demonstrating that the proper design of aerial
tramways is based on sound principles of engineering, and that such
systems of transportation are not to be considered as expedients to
be adopted when no other method can be used. Aerial tramways are
safe, sane, and satisfactory.




This Society is not responsible for any statement made or opinion expressed
in its publications.

Paper No. 1395


By William M. Hall, M. Am. Soc. C. E.

With Discussion by Messrs. John W. Hill, Alexander Potter,
George W. Fuller, Nicholas S. Hill, Jr., Walter E. Spear,
T. Kennard Thomson, H. F. Dunham, Theodore S. Johnson,
Philip Burgess, James H. Fuertes, Morris Knowles and J. D.
Stevenson, Edward Mayo Tolman, and William M. Hall.

This paper describes the process of selecting a new water supply
for the City of Parkersburg, W. Va., the investigation of the possible
sources of supply, especially the natural underground supply in the
neighboring Ohio River bottoms and plateau, the physical and geo-
logical phenomena relating thereto, the methods considered for collect-
ing the water for pumping, and the novel method finally adopted, which
consists of an infiltration system composed of strainer pipes laid in
the bed of the river and overlaid with a bed of washed gravel and sand.

Introduction. -

The City of Parkersburg, W. Va. (population 17 S42 in 1910),
constructed works for a public water supply in 1884. The pumping
station was established on the banks of the Ohio River, and for more
than 25 years the supply was drawn from the muddy and polluted
waters of that stream, and used for all purposes without any treatment
whatever. With increasing quantities of sewage entering the river
from Pittsburgh, Wheeling, and other communities in the Ohio Valley

* Presented at the meeting of February 21st, 1917.


above Parkersburg, this supply became increasingly unsatisfactory.
Typhoid fever vs^as quite prevalent, and investigations in 1906 and
1907 indicated for that disease annual death rates of 75 and 60,
respectively, per 100 000 population.

In 1907 a law was enacted creating for Parkersburg a Water-Works
Commission, composed of three city officials, including the Mayor,
and four citizens, of whom the writer was one.* This Commission
instituted investigations for the purpose of determining the best metliod
of treatment of the Ohio River water, if that should continue to be
the supply, and whether or not water could be obtained from wells,
cribs, or from a gravity source. As a part of the project, consider-
ation was also given to a new pumping station to supersede the original
plant, which had suffered much from wear and tear in pumping muddy
water for such a long time. It is not within the scope of this paper
to describe the details of the pumping station, distributing reservoirs,
pipe lines, etc.

Preliminary Investigations.

Morris Knowles, M. Am. Soc. C. E., was engaged to make recom-
mendations relative to a new water supply. In addition to gravity and
impounding sources of supply and filtration of the Ohio River water,
he investigated the feasibility of obtaining a well-water supply from
the Camden Farm, which lies immediately north of the upper city
limits of Parkersburg. This is shovrai by Fig. 1.

Mr. Knowles reported in August, 1908, for a recommended 4 000 000-
gal. daily supply, that, although the well proposition was attractive,
further investigation should be made, perhaps in other localities, or
somewhat removed from the Camden Farm. His test of a 12-in.
well did not indicate a serious lowering of the ground-water level, but,
for safety, a more elaborate test was recommended, as it was realized
that a large factor of safety should be required in establishing a
well plant. Based on his recommendations, the citizens voted on
April 22d, 1909, to authorize a bond issue of $270 000 to build the
proposed new water-works; and he was authorized to prepare plans
and specifications for the construction thereof.

* The Commission consisted of Messrs. W. D. Pedigo, Mayor, C. D. Forrer, of the
Board of Affairs, Walter Gerwig, Councilman, and the following citizen members :
Messrs. S. D. Camden, H. H. Moss, B. S. Pope, and the writer. Mr. Camden was elected
President of the Commission, and Mr. Forrer, Secretary. After the expiration of Mr.
Forrer's term of office, Mr. George P. Chase, Attorney, though not a member of the Com-
mission, served as Secretary.



Fig. 1.


Some doubt as to the permanency of the well-water supply arose
in the minds of some of the city officials, and, on request, further
consideration was given to the matter in July, 1909, by Mr. Knowles,
who called in Mr. F. G. Clapp, a geologist, as advisor on this subject.
Mr. Clapp favored the well-water supply, but was also aware of the
possibility of having to build new wells in future yeax-s, thus making
it wise to secure at the outset plenty of land in the vicinity of the
projected plant; such additional land would also protect the purity
of the supply by avoiding surface pollution near the wells.

There was still one member of the Water-Works Commission who
was unable to agree with the otherwise unanimous opinion as to the
adequacy of the proposed well supply and its suitability as to quality.
To obtain further data, James H. Fuertes and George W. Fuller,
Members, Am. Soc. C. E., were engaged in November, 1909, to inves-
tigate and report on the proposed well supply, with a view to settling
the diilerences of opinion between the city officials and the citizen
members of the Water-Works Commission. They investigated the
well-water project with considerable thoroughness, and found that,
though it would be possible to obtain a 4 000 000-gal. supply from the
gravel and sand layers underlying the bottom-lands in the neighborhood
of the Camden Farm, it would be necessary that such a well system
should extend along the river for at least 4 000 ft., thus making its
cost greater than that of a filtered-water supply from the river. They
recommended the adoption of the latter.

The city officials passed an ordinance authorizing the Board of
Affairs to build the filtration works and appurtenances, but this authori-
zation was nullified by an injunction suit which stopped the further
expenditure of fimds, made available by the bond issue for the purpose,
without the approval of the Water- Works Commission. In the mean-
time Mr. L. E. Smith interested some of the leading citizens in a
system of water supply consisting of a manifold of pipes laid in a
sand bar in the Ohio Eiver. Samuel M. Gray, M. Am. Soc. C. E., was
then engaged to report on the advisability of adopting the so-called
Smith system. His report, delivered on May 26th, 1910, being favorable,
the works were built under his direction, and for 5 years or more the
water has been clear, clean, and of satisfactory sanitary quality. Not
only has the new water supply been satisfactory to the citizens, but
it is gratifying to note that the new pumping equipment has effected


an economy sufficient to pay the capital charges on the bond issue
required by the new plant.

It is believed that the development of the new supply has placed
on record many data of general interest to the Profession with regard
to ground-water; and that this is so with respect to the investigation
of the well-water supply by Messrs. Knowles, Fuertes, and Fuller, and
in particular in the case of the somewhat novel system built by Mr.
Smith under the direction of Mr. Gray. In placing before the Society
the principal features of the Parkersburg water project, the writer
feels of necessity bound to make liberal use of the reports of the
above-mentioned gentlemen, and wishes to state that much of the
following is an abstract compiled from their several reports in the
preparation of which he is indebted to them.

Geological Conditions.

The geological conditions of the Ohio Valley in the vicinity of
Parkersburg were investigated at length by Mr. Knowles with the aid
of Mr. F. G. Clapp.

Attention is first directed to the cross-sectional profile of the Ohio
Kiver at Lock and Dam No. 18 (Fig. 2), furnished by the writer
from investigations made under his direction.

The bottom-lands on the West Virginia bank of the Ohio River,
for a distance of 5 or 6 miles north of and above Parkersburg, contain
more or less water-bearing strata. This is shown by numerous wells
in successful use for domestic and manufacturing purposes within
that tract, and is also confirmed by an examination of the materials
removed in drilling these wells.

From a study of the history of the Ohio River in this immediate
locality, it appears that the river bed has shifted its position materially
along the part south of the promontory at Briscoe, where the rock of
the West Virginia shore extends down to and beneath the river bed.
At present the Ohio lies well to the west in the river bottoms, in some
places nearly reaching the foot of the hills forming the rugged upland
of the Ohio shore. In earlier days the river unquestionably skirted
the West Virginia foot-hills. The result of this shifting has been
the deposition of a substantial quantity of gravel and sand in the
present bottom-lands, with a stratum of sandy gravel extending north
from above the upper limits of the City of Parkersburg for about
5 miles, and having a varying width averaging perhaps | mile.




This stratum varies in depth from perhaps 15 to 25 ft., and averages
approximately 20 ft., according to available information. It is over-
laid with a stratum of loam ranging in depth from 25 to 40 ft. The
bottom of the sand and gravel stratum varies in elevation roughly
from about 540 to 550 ft. above sea level, and its top surface from
about 560 to 570 ft.

A more detailed statement of the local geology, with comments
on its significance with reference to the ground-water supply of Parkers-
burg, is set forth with various comments by Mr. Clapp in the following

Local Geological Details. — In order to make sure of the adequacy
of the present and future supply, the formation of the valley and
its sediments was carefully considered. The real bottom of the Ohio
Valley is not the present surface of the river or of the first and second
bottoms, but is the bed-rock surface, or surface of the solid rock (sand-
stone and shale) underlying these. Along the part of the valley con-
sidered, this bed-rock surface lies from 50 to 125 ft. or more below
the first bottoms, as determined by the depth of numerous wells and
test borings.

The origin of the buried bed-rock surface is due to erosion at a
time — thousands of years ago — before the overlying gravel filling
existed, when the whole country stood higher above the ocean level,
and hence the present bed-rock was at the surface of the ground.
The deeper parts of the bed-rock valley {i. e., those now buried more
than 100 ft. below the present bottoms) were eroded by the ancient
Ohio River as it cut its way deeper into the surface of the country
while it was comparatively high, forming a sort of gorge below the
general level of the bed-rock surface in the valley. Thus there were
(and still are) three rock levels: (1) that of the gorge, now from 100
to 125 ft. below the present first bottoms; (2) that of the ordinary
bed-rock in the valley, now from 50 to 90 ft. below the first bottoms;
and (3) that of the surrounding hills, the tops of which stand from
200 to 300 ft. above the bottoms. The sand, gravel, and clay filling
which forms the bottoms and higher unconsolidated terraces along the
valley was formed at a more recent date than the rock valleys, due
to various incidents in connection with the Ice Age, during which
the northern part of the territory now occupied by the State of Ohio


was covered with a great glacier, damming the river valleys at various

For the most part, the huried bed-rock surface of the Ohio Valley
is rather flat, and, under the Camden Farm and elsewhere, it lies from
60 to 90 ft. below the lower bottoms. On this rock bench rest the water-
bearing gravels, from 20 to 30 ft. thick, from which it is proposed to
draw the water supply by pumping from wells. The gravels are covered
by clay, fine sand, and loam, reaching to the surface of the bottom-land.
Many household wells driven into the gravels, and also geological
inferences, have shown that the formation is similar and continues for
miles up and down the main valley.

No part of the rock gorge underlies the Camden Farm, but at this
place it is below the present river. Presumably it meanders from side
to side of the valley, and farther up and down stream it may underlie
the gravels, as it does at the test wells on the land of the Parkersburg
Iron and Steel Company. In order to show that this deeper gorge will
not interfere with the supply of the wells by draining off the water
at a lower level, it may be stated that the deeper gorge is filled for
the most part with finer material, such as fine sand and clay, and these
do not hold large volumes of water. Moreover, the portion of the
underflow of the river which follows the gorge is separated from the
water in the upper gravels by layers of finer, more impervious material,
which tend to keep the two bodies of water separate.

Another geological feature which needs consideration is the terrace
known as the "sand plains region",, lying back of Boreman Hill, and
standing at an average elevation of 80 ft. above the first bottoms, or
130 ft. above the underlying bed-rock. The sand plains are about
1/2 mile wide, and extend from the bottom-lands of the Ohio Valley
at Beechwood for 1/2 mile to Worthington Creek. It is a geological fact,
based on good evidence, derived from what is known of similar sand
plain regions at various places along the Ohio, that this strip was
the ancient valley of Worthington Creek, or the Little Kanawha River.
The depth of the sand and gravel filling there is unknown, but it is
considerable; and through shallow wells which have been drilled there,
it is known that it contains a large volume of water. This water is
supplied by the rain which falls on the sand plains and flows west-
ward, through the underlying sand and gravel, to the Ohio Valley,


where a large part of it passes through the gravels underlying the
Camden Farm.

Thus there will be two sources of supply for the wells : the ground-
water from the sand plain district, and that from the bottom-lands
in the main valley of the Ohio, both bodies of water moving toward
the wells. At no other locality in the vicinity could this double supply
be obtained in such great quantity.

Gravel-Water versus Rock-Water. — The question arises: Can a
better or more adequate supply of ground-water be obtained by drilling
to some lower level than is planned, that is, into the bed-rock? To
this question the reply is decisively "no". The rocks underlying the
river valleys and the entire vicinity of Parkersburg are similar in
character to those in the surrounding hills, and consist of shales and
sandstones of the Dunkard formation (upper barren coal measures),
which contain very little water, and nowhere in these rocks could a
sufficient supply be obtained. In fact, a supply as large as is neces-
sary does not seem to exist anywhere in the shales and sandstones
of the coal measures, or in the thin limestones scattered through them.
Many hundred feet below the surface of the valley, a large enough
supply could be found in limestones, but, even if it was practicable
to sink wells to that depth, the water would be found to be salty and
unfit for use.

Estimated Yield of the Wells. — Calculations by Mr. Clapp agreed
with those by Mr. Knowles, that fourteen wells will yield from 3 000 000
to 4 000 000 gal. of water per day, which is more than is at present
needed, and will suffice for some years to come. However, after from
8 to 12 years, it may be necessary to add a new well every year or two
for several years, in order to keep pace with the increase in population
and to replace possible deteriorating wells. Hence, plenty of land
should be secured in the vicinity of the wells. Owing to the character
of the water, and the known type of river gravels, the wells may last
15 years or more without the necessity of being replaced. In order
that the supply may be maintained at approximately its initial quan-
tity, the wells should be cleaned occasionally, and, if pumped with an
air-lift, the air pressure should be reversed frequently, in order to
blow out any fine material which may collect in the pores of the
gravel close to the wells or in the strainers.


Arrangement of the Wells. — The water in the gravels is moving
in two directions. A part of it, derived from the rainfall on the
bottom-lands farther up the valley, is moving slowly down stream,
approximately parallel to the Ohio River. A second part of the
gravel-water, derived from the rainfall on the sand plains, is moving
from them toward the river, in general at right angles to it. There-
fore, the proposed arrangement of the wells in two lines, one parallel
to the river and the other at right angles thereto, is the best for
securing all available water. The wells should be at least 300 ft. apart.

Hydraulics of the Local Well- Water Field.

So much discussion having arisen in Parkersburg as to the relative
merits of a well-water supply and a filtered-water supply from the Ohio
River when Messrs. Fuertes and Fuller made their examination in
the fall of 1909, it was determined to conduct pumping tests for a
period of at least 3 weeks. Accordingly, a deep-well pump was set
up in one of the 12-in. wells sunk by Mr. Knowles. This pump was
operated under the observation of James R. McClintock, M. Am.
Soc. C. E., from January 18th to February 8th, 1910, and during this
period quantities ranging from 480 000 to 575 000 gal. daily were
pumped. Eight special observation wells were driven, and frequent
studies were made of the water level therein, and also in thirty-one
existing driven wells within 3 or 4 miles up the river on the Camden
Farm site, including two wells in the sand plains east of the bottom-

Water levels in the river were taken several times a day, and
samples of the well water were collected frequently for analysis. The
temperature of the well water was uniformly between 51 and 52°
Fahr., and that of the river water during the period under observation
ranged from 34 to 38° Fahr.

Summary of Results of Studies of Ground-Water Supply, as to
Source, Quality, and Quantity.

The results of the pumping tests are given in a report by Messrs.
Fuertes and Fuller, dated February 21st, 1910, with perhaps unusual
clearness, and a summary of this information is given at some length,
as follows.


Water-hearing Strata. — The first essential in securing a ground-
water supply was to ascertain the conditions with respect to the water-
bearing strata, as it is obvious that without such strata a ground-water
supply for the city was out of the question. Reference has already
been made to the local geological conditions, and these may be further
spoken of from the standpoint of water supply as to the character
of the water-bearing strata.

The elevation of the Ohio River opposite the Camden Farm ranges
from about 562 at low water to about 621 for extreme high water, which
floods the bottom-lands to a depth of from 10 to 20 ft. At low water
the depth of the river varies somewhat, but approximates 5 ft., accord-
ing to the surveys made by the United States Government.

The present river bed opposite the low lands in question is made
up largely of sand and gravel. The proportion of gravel and the range
in gravel size vary considerably. The proportion of sand apparently
increases with the distance from the natural dam at Briscoe.

Excellent building sand for local construction work is secured
from the river bed by dredging at a point opposite the Camden Farm.
Samples of this sand, after removing the gravel by screening, show
what would be called a medium river sand, having an "effective size"
of about 0.28 mm. Test wells sunk by Mr. Knowles, and from which
samples of material were placed on exhibition in the rooms of the
Water Commission, show a substantial proportion of relatively fine
or medium-sized gravel from which the sand was largely eliminated
in the process of removal from the ground. So far as it has been
possible to ascertain, these bottom-lands, at a depth of about 40 ft.
below the surface, contain a sand and gravel layer with the sand
predominating. The sand is of medium size, filling the voids of the

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