GENERAL STATEMENTS.
Estimates of flood damages are always approximations only. It is
possible to determine with a fair degree of assurance the cost of
replacing structures which have been carried away, to estimate the value
of goods destroyed—especially if they be commodities stored in shops or
warehouses—to calculate the amount of operatives' wages lost, and in
the case of general mercantile business to estimate the damages incurred
through consequent reduction of trade. Destruction by flood, however
vast, is incomplete. It differs materially from destruction by fire, for
often destructible property is of value after floods have passed.
Buildings which are inundated still retain value, and many kinds of
merchandise are not totally destroyed. Therefore when the amount of
damages is calculated there is always to be taken into consideration the
fact that a part of the material which has been flooded can be
reclaimed, and retains some proportion, at least, of the value which it
had previously possessed. Furthermore, damages by flood enter into
practically every detail of social and business affairs. There are
losses which are severe to one or more persons, and which can not be
appreciated except by those whom the floods have actually overtaken.
Therefore estimations of flood damages can be only approximate, and
while a measure of accuracy may be reached with respect to a part of the
losses, there remains a necessity for approximation which can not be
classed with carefully computed damages along other lines.
HIGHLAND TRIBUTARIES.
Along the three northern tributaries, the Ramapo, Wanaque, and Pequanac,
and at their confluence with the Pompton, the destruction by flood
waters was far greater than along the Rockaway, Whippany, and upper
Passaic, or in that area described as the Central Basin. In the drainage
areas of the three tributaries last mentioned the waters were higher
than in the flood of 1902, but the general effects were of the same
nature, and consisted principally of flooded lands, houses, and
washouts. There were few radical cases of complete destruction like
those which marked the course of the flood in the northern tributaries.
The principal interest is therefore confined to the Pompton and the
three highland tributaries which discharge into it.
Ramapo River.—The greatest destruction was along the Ramapo. It is
the largest of the upland branches, and was therefore the heaviest
contributor to the main stream. Throughout the flood period the stream
was especially violent, causing great apprehension in the lower valley.
The destruction along several stretches of the valley was almost
complete. Nearly all the dams failed, and every bridge across the river,
with one exception, was carried away. Some small villages were swept
bare, and the damages to realty value and personal property were
excessive.
It was only by strenuous measures that the dam impounding the waters of
Tuxedo Lake was saved. If this had failed the destruction along the
entire course of the river, even to the cities in the lower valley,
would have been enormously increased.
The dam at Cranberry Pond, in Arden, failed in the early part of the
storm, the flood waters disabling the Tuxedo electric-light plant and
inundating the Italian settlements along the river below. The failure of
the dam conserving the waters of Nigger Pond, which lies at the head of
a small tributary emptying into the Ramapo below Tuxedo, resulted in the
inundation of Ramapo village. The village of Sloatsburg was practically
obliterated.
The damage at Pompton Lakes was especially severe. During the early part
of the flood the timber dam of the Ludlum Steel and Iron Company, which
raised the water to a height of 27 feet, and afforded 7.04 horsepower
per foot fall, was carried away with a part of the headrace. (See Pl.
II, A.) This sudden emptying of Pompton Lake, an expanse of 196 acres
(see Pl. II, B), was extremely destructive to Pompton Plains, and the
destruction of the dams above on Ramapo River, which followed some time
after the bursting of the lower dam, refilled Pompton Lake above its
former level, and caused greater damage than that which resulted from
the failure of Pompton dam itself. The large iron bridge just below the
dam was carried away, with the stores of the Ludlum Steel and Iron
Company. The river front along this company's property was destroyed,
along with coal docks at the head of Morris Canal feeder. The channel of
the river below the dam is filled with débris, which will raise the
height of the water in the tailrace, and unless it is cleared will
diminish the available power at the iron works. It has been
authoritatively announced, however, that the power facilities will not
be restored, as the Ludlum Steel and Iron Company is preparing to use
steam power exclusively.
Pequanac and Wanaque rivers.—Along Pequanac River the principal
damage consisted of washed-out roads and destroyed bridges. The large
ponded area in this basin was practically full at the time of the flood,
and, as measurements at Macopin dam show, the run-off per square mile
was extremely large. In the Wanaque drainage area the storage facilities
afforded at Greenwood Lake were probably useful in holding back a part
of the water for a brief period, but the damages along the stream are
comparable to those of the Pequanac.
The effect of the flow from these two streams, added to that of the
Ramapo, was particularly disastrous over the Pompton Plains. Three
| U. S. GEOLOGICAL SURVEY | WATER-SUPPLY PAPER NO. 92 PL. II |
A. POMPTON LAKES DAM AND WATER FRONT OF LUDLUM STEEL
AND IRON COMPANY.
B. DRY BED OF POMPTON LAKE.
| U. S. GEOLOGICAL SURVEY | WATER-SUPPLY PAPER NO. 92 PL. III |
FLOOD DISTRICT OF PATERSON, N. J.
bridges at Pompton station, over Wanaque and Pequanac rivers, were
carried away, and in the end one bridge only remained over Pompton
River, that at Pequanac station. In all about 100 houses were inundated
on Pompton Plains, and the damage to roads and culverts was particularly
severe.
The total loss in the drainage area of Pompton River was $350,000.
CENTRAL BASIN.
Over the Central Basin there was the usual impounding of flood waters,
but the effects were not materially different from those described in
the report on the flood of 1902. The damage along this basin from floods
of this character is accumulative by reason of the fact that the
presence of water over the land for so long a period kills the desirable
feed grasses and fosters in their place the coarse meadow grass. This
effect has been observed for some years, particularly since the flood of
1896. It is estimated that over the Central Basin the damage to crops
and arable land alone arising from the floods of 1902 and 1903 amounts
to $300,000. A statement of the damage arising from the later flood can
not separately be made, as its effect upon the fertility of the meadow
lands can not be determined without the experience of a planting season.
LOWER VALLEY.
The flow of the stream through the constricted channel at Little Falls
and on to Great Falls at Paterson is given in the weir measurements on
page 17. It was attended by comparatively large damages, the features of
which were not materially different from those described in the previous
report. The pumping station of the East Jersey Water Company, situated
just below Little Falls dam, did not suffer as severely as during the
previous flood, by reason of the fact that extensive and effective
barricades were placed so as to keep a large part of the water away from
the pumps. This was not accomplished in the flood of 1902. The total
damage in this district amounted to nearly $200,000.
The channel contours were changed somewhat in this portion of the
stream. In the river at the pumping station of the East Jersey Water
Company there was completed a somewhat interesting cycle of changes,
described in the following extract of a letter from Mr. G. Waldo Smith,
chief engineer for the New York aqueduct commissioners, and formerly
engineer and superintendent of the East Jersey Water Company:
"No better illustration of the old adage, 'The river claims its own,'
could be given than that offered by the action of Passaic River at
Little Falls, New Jersey, at the point where the works of the East
Jersey Water Company have been constructed. These works were built
between 1897 and 1900. In the course of the work the river channel for a
distance of several thousand feet down stream from the power house was
drained and improved, so that the head on the wheels at the ordinary
stage of the river was increased about 6 feet. From the time this
improvement was completed to March, 1902, through the action of the
ordinary flow of water and moderate floods, this head had been reduced
about one-third. The great freshet of March, 1902, cut off about another
third, and the recent flood has completed the cycle and entirely wiped
out the benefit due to the river improvement, and the water at the
pumping station stands now at almost precisely the same level that it
stood before any improvements were undertaken. New bars were formed in
approximately the same location as they existed before, and, so far as
possible, except for the changed conditions brought about by the
building of the power station, the condition of the river is not
dissimilar to that existing when the work was commenced.
"In this connection it might be well to state that a New Jersey drainage
commission, in blasting out a channel below the Little Falls dam some
years ago, dumped a considerable portion of the excavation in the deep
water under the Morris Canal viaduct.
"The action of the two great floods, March, 1902, and October, 1903, has
washed a large part of this material out of this deep hole and piled it
up in the river about 300 feet below where the river widens, and reduces
the force of the current.
"I have made no estimate of the amount of material deposited in the
river, but offhand should say that it would be at least 100,000 yards."
Paterson.—The flood district in the city of Paterson (see Pl. III)
comprised 196 acres and involved the temporary obstruction of 10.3 miles
of streets. Along the streets close to the river banks the height of
water was 12 feet, sufficient to inundate the first floors of all the
buildings (see Pl. I, B), and in some cases to reach to the second
floor. During this flood period householders who remained at their homes
were compelled to use boats, while in the more exposed places the danger
was too great to admit of remaining, and at one time 1,200 persons were
housed and fed in the National Guard armory at Paterson.
The bridges crossing Passaic River in Passaic, Essex, and Bergen
counties were almost completely destroyed, and the damage amounted to
$654,811. Within the limits of Paterson, below Great Falls, all of the
highway bridges except two were either severely damaged or completely
carried away. West street bridge, the first below the falls, was a Melan
concrete, steel-arch structure, built in 1897, and costing $65,000. It
was composed of three spans, each about 90 feet long. The flood
practically split two spans longitudinally, the upstream side of each,
equal to about one-third of the width of the bridge, being carried away.
| U. S. GEOLOGICAL SURVEY | WATER-SUPPLY PAPER NO. 92 PL. IV |
A. WASHOUT AT SPRUCE STREET, PATERSON, N. J.
B. RIVER STREET, PATERSON, N. J., AFTER FLOOD.
| U. S. GEOLOGICAL SURVEY | WATER-SUPPLY PAPER NO. 92 PL. V |
A. EFFECTS OF FLOOD IN MILL DISTRICT, PATERSON, N. J.
B. THE WRECK OF A HOTEL IN PATERSON, N. J.
This structure was built to conform to the established grades of
streets on both sides of the river and was completely inundated, forming
a barrier for floating débris and practically making a dam in the river.
Main street bridge is a 3-span, steel-arch structure, which was
completely covered during the flood, but was only slightly injured. Arch
street bridge, built in 1902 to take the place of a structure carried
away by the March flood, was a concrete-arch bridge of three spans. It
was undermined at the north pier and collapsed, being practically
destroyed. The original cost of this bridge was $34,000. Its piers
presented a serious obstruction to the flow of the stream, especially as
the channel is very narrow at this point. In addition to this, the
bridge was of low grade and admirably adapted for deterring flood flow.
Below Arch street bridge all the other structures crossing the Passaic
were of iron and were carried away, with the exception of Sixth avenue
and Wesel bridges. Those destroyed were designated as follows: Straight
street, Hillman street, Moffat, Wagaraw, Fifth avenue, East Thirty-third
street, and Broadway bridges. All these structures were built too low,
and were inundated during the early stages of the flood.
The damage to real property, stock, and household goods in the city of
Paterson amounted, according to certified returns, to about $2,700,000.
It is impossible to secure correct figures, because merchants and
manufacturers refuse to give details of losses, fearing that the
publication thereof would affect their credit. General ideas concerning
the destruction by the flood can be gathered from Pls. I, B, III, IV,
V, and VI.
Passaic and vicinity.—Below the city of Paterson destruction was as
complete as in Paterson, although the damage was not as great because
the improvements were not as valuable. Damage to property, exclusive of
public works, in this region, amounted to about $1,250,000. This
estimate does not take into consideration losses by manufacturers
arising from destruction of raw materials or finished products. The
flood was about 4-1/2 feet higher than that of 1902. (See Pl. VII, A.)
On the right bank of Passaic River, in the city of Passaic, the damage
was severe, especially to manufacturing plants. In addition to the flood
in the Passaic itself, the bursting of Morris Canal, a few miles east of
Passaic, flooded Wesel Brook, which in Passaic is used as the tail-race
of the Dundee Power Company. The capacity of Wesel Brook channel is
limited, and the extraordinary amount of water which was turned into it
carried away all culverts and bridges from Richfield to Passaic.
Below Passaic, along the river front of Essex County, the damages to
bridges amounted to $50,000. (See Pl. VII, B.) The loss due to
washouts in roads throughout the county amounted to $15,000. The
effects of the flood were apparent along the entire length of the river
and into Newark Bay. The damage from inundation in Newark and vicinity
amounted to $753,199.
The figures above given with reference to damage along Passaic River are
uncommonly accurate, being for the most part the result of a
house-to-house canvass by the northern New Jersey flood commission. As
has been stated above, tradesmen are reluctant to give full details with
reference to their losses through fear of injured credit. Roughly
estimating the damage as a whole, and taking into consideration factors
which were given to the writer confidentially, the damage throughout the
drainage area from this flood will amount to not less than $7,000,000.
GENERAL DISCUSSION.
In the consideration of means of preventing damages by floods every plan
proposed falls under one of two general heads—the storage of flood
waters or an increase in the capacity of the streams.
The first plan involves the construction at selected localities of
reservoirs of sufficient size to hold all or a greater part of the
waters which run over the surface during and after storms. This plan is
not practicable except where valleys or plains are inclosed by high
ridges and these ridges approach sufficiently near each other to admit
of the economical construction of a bank or dam across the gorge or bed
of the stream which flows through, so that the inclosure will be
complete and form a water-tight basin. Where such a reservoir exists the
water can be held back and gradually let down through properly provided
gates so that the channel will not be flooded.
For flood purposes alone it would be necessary to provide reservoirs of
sufficient capacity to contain the run-off waters resulting from the
largest storms. With such provisions it would be necessary to entirely
empty the reservoir as soon as possible after a storm had passed and
leave its full capacity available for the next storm. It is therefore
better, wherever possible, to provide a reservoir capacity considerably
larger than that represented by the run-off from the heaviest storms, so
that water may be stored for use as power or domestic supply. With such
provision it is necessary merely to draw from the reservoir water to a
depth equivalent to the stream run-off in the drainage area above.
The second plan for prevention of flood damages involves provisions for
letting the flood water out rapidly by removing obstructions to its flow
by straightening and deepening the channels and providing long
embankments, dikes, or levees which rise above the ordinary river level
to a height exceeding that of the stream during its highest floods. This
plan is most generally followed in the case of large rivers like
| U. S. GEOLOGICAL SURVEY | WATER-SUPPLY PAPER NO. 92 PL. VI |
A. DEVASTATION IN HEBREW QUARTER, PATERSON, N. J.
B. A COMMON EXAMPLE OF FLOOD DAMAGE.
| U. S. GEOLOGICAL SURVEY | WATER-SUPPLY PAPER NO. 92 PL. VII |
A. INUNDATED LANDS AT PASSAIC, N. J.
B. UNDAMAGED BRIDGE ACROSS PASSAIC RIVER AFTER PARTIAL
SUBSIDENCE OF FLOOD.
the Mississippi, where the contributing area is enormous and the
conservation of the waters would be impracticable even if the nature of
the country would admit of the construction of reservoirs. In
Switzerland, where the torrents occasioned by the rapidly melting snows
are especially destructive, the flood waters are confined by a series of
parallel dikes on each side of the river, which have the effect of
dividing the flow into several parallel streams. As the main river
channel fills and overflows the inner dikes, the overflow water collects
into the first series of parallel channels, and when a height is reached
at which the second dikes are overflowed the water collects into the
third, and so on. This gives an enormous carrying capacity, the limit of
which is approached slowly, and therefore abundant opportunity is
afforded for preparation upon the part of the riparian owner.
The drainage basin of Passaic River is admirably adapted to the
development of the conservation system. At its headwaters in the
mountains of northern New Jersey are numerous sites for reservoirs. The
comparatively limited area draining into Passaic River makes such a
scheme relatively inexpensive. On the other hand there is abundant
opportunity for effective work in removing obstructions and
straightening and deepening the channel of the lower river. So that, all
things considered, the prevention of flood damages in the Passaic Basin
can be best accomplished by a combination of the two general methods
above outlined.
LOWER VALLEY IMPROVEMENTS.
The channel of Passaic River below Great Falls, at Paterson, is of
limited capacity. To anyone making an inspection, especially within the
city of Paterson, it is readily apparent that the river bed has for
years been considered a legitimate field for encroachment. Owners of
lands fronting on the river have increased their holdings by filling in
beyond the channel line. Buildings have been erected upon these tracts
and the builders have not hesitated to extend retaining walls still
farther into the river bed. Refuse from the city's streets, light and
unstable in character, has been freely deposited upon the bank to be
carried out into the river. Thus the channel has been constricted
laterally, the bottom raised, and there is left for the flood waters no
alternative than that of extending themselves in the upward direction.
It would seem that this, at least, should have been unobstructed. Such,
however, is not the case.
The bridges across the Passaic have apparently been erected without
reference to channel capacity. The authorities have evidently considered
it more important to retain established approach levels than to provide
proper capacity for river water. As an example the following instance
may be cited: During the flood of 1902 a steel truss bridge across the
river in Paterson was carried away. The point of crossing was one of
the narrowest places in the stream and it should have been clear to
everyone that the space beneath the bridge was not large enough to carry
flood waters. It should have been apparent that a new bridge, if erected
at that point, must be higher than the old one, to be thoroughly safe.
Notwithstanding, the new bridge was erected at the level of the old one,
and in addition to this, it was a concrete arch structure, and the great
piers and low arch springs reduced the former channel capacity about 15
per cent. This new bridge, as might be expected, collapsed during the
October flood.
Along the entire course of the stream in the lower valley we find a
continuation of instances of unreasonable encroachment and
ill-considered bridge engineering, and there is opportunity for
relieving a large part of the purely local obstructions by straightening
the channel at chosen points.
Although this matter has not been thoroughly investigated it is readily
apparent to one traversing the river bank that considerable relief may
be secured in this manner. Damage, however, can not be prevented by this
means alone. It would, of course, be possible to erect high and
resistant levees along the entire course of the river, but this would be
extremely expensive and would destroy the water front for commercial
purposes. In fact, such a plan is quite visionary. At the present time
there are no obstructions in lower Passaic River the removal of which
would give relief in the event of floods like those of 1902 and 1903.
When one considers the amount of water which was carried into the lower
valley, the heights which it reached, and the area which it inundated,
the futility of any local improvement except levee construction is
emphasized. The present channel of the river will not carry without
damage the amount of water recently thrown into it, and while it is
important to provide regulations which will in the future prevent
encroachment, and which will correct the evils now present along the
channel, these measures can not, operating of themselves, give relief
from flood devastation. Immunity from flood destruction in the Passaic
must come, if it ever comes, from the construction of flood-catchment
reservoirs in the uplands.
It is not necessary to spend any great amount of time in determining the
cause of floods upon the Passaic. A review of the flood history of this
river shows that in every case floods arise from extraordinary
precipitation. High waters occur through the melting of snows and during
periods of abundant rain. The heavy floods which have been regarded as
extraordinary are clearly the result of unusual conditions of
precipitation. The river carries the usual flood waters, and no damage
is done until the water poured into it is far beyond its carrying
capacity. Therefore the provisions which are made for preventing damage
by floods must, if they be effective, be designed to meet extraordinary
conditions, and means which would prove effectual in ordinary cases
will not stand the test. In order to appreciate the extent of the flood
in the lower valley it is necessary to visit the flooded area and
observe the points of flood height. Unless one does this he will be very
readily deceived when he considers means of flood prevention.
FLOOD CATCHMENT.
Among the highland tributaries of Passaic River there are three
principal areas where storage reservoirs for flood catchment may be
placed: (1) The Ramapo, Wanaque, and Pequanac drainage basins, from
which the waters are carried into the central basin by Pompton River;
(2) the Rockaway drainage basin, and (3) the upper Passaic drainage
basin. The remaining principal tributary of Passaic River, the Whippany,
is not well provided with storage reservoir sites. The combined capacity
of catchment reservoirs which could be constructed in these drainage
areas is considerably more than the volume of the heaviest known
rainfall, that of October 8-11, 1903.
In the description of reservoir possibilities in the following pages the
data with reference to many of the basins are computed from planimeter
and other measurements, the United States Geological Survey topographic
maps being used as a base. The measurements are therefore not of refined
accuracy but suffice for the purpose in view—that of showing flood
catchment possibilities.
POMPTON RESERVOIR.
There are in the Pompton system several sites on Ramapo, Wanaque, and
Pequanac rivers which, if utilized, would afford sufficient storage for
flood catchment purposes, but the entire flow of the river system may be
conserved in what has been described as the Pompton reservoir. This
project was first presented by Mr. C. C. Vermeule in the year 1884, the
details being described at some length in the Engineering News, of April
12 of that year, pages 169-171. In this article Mr. Vermeule presented
the possibilities of Pompton reservoir for use as an additional water
supply for the city of New York, at the time when the Quaker Bridge
reservoir on the Croton watershed was being considered. A few pertinent
quotations from this article may be of interest:
This basin, subdivided by minor ridges which cross it, furnishes
several admirable sites for large storage reservoirs, with
catchments from 50 to 400 square miles in area, lying above on the
primitive rock of the Highlands. About 6 miles of the northeastern
end of the basin is cut off by Hook Mountain, a small ridge of trap
which crosses it from east to west, inclosing a basin 21 square
miles in area, known as Pompton Plains, having its outlet at
Mountain View, 5 miles west of Paterson, at a pass in Hook
Mountain, through which the Pompton River flows to join the
Passaic, 2 miles below. This pass is the gateway by which the
Delaware, Lackawanna and Western Railroad, the New York and
Greenwood Lake Railway, and the Morris Canal enter the plains. The
basin is also crossed near its head, above Pompton, by the New
York, Susquehanna and Western Railroad. Pg032
The Pompton River has a drainage area above Mountain View of 420
square miles. It is formed near the head of the basin by the
confluence of the Pequanac from the northwest, the Wanaque from the
north, and the Ramapo from the northeast. * * *
The entire flow from this watershed may be stored by building a dam
across the gap at Mountain View and converting Pompton Plains into
a great lake covering an area of 21 square miles. The elevation of
the river at the gap is 168 feet. The slopes in the basin being
gentle up to an elevation of 220 feet and abrupt beyond it, it will
be advisable to take this as the minimum or low-water level of our
reservoir. It is generally estimated that 25 per cent of the volume
of the mean annual rain on a given catchment is sufficient
reservoir capacity to fully utilize the flood flows. We have long
series of observations of rainfall at three points, which may be
taken to fairly represent the Passaic catchment. At Newark the mean
annual rainfall is 46.2 inches, at Paterson, 50 inches, and at Lake
Hopatcong, 42. The last being on the Highlands, like most of our
watersheds, is perhaps the safest to use. Now, 25 per cent of 42.5
inches, 10.62 inches, which, on 420 square miles, give a volume of
10,362,000,000 cubic feet, the necessary capacity of reservoir.
By raising our reservoir to 240 feet when full we secure a capacity
of 10,493,000,000 cubic feet, or ample to utilize the heaviest
floods of the watershed. This gives a beautiful sheet of water 21.1
square miles in area, with bold, rocky shores, and a depth at dam
of 72 feet. We secure the above capacity by uncovering but 22 per
cent of the reservoir bottom; and, as we shall presently see, we
shall rarely need more than half this storage, and probably not
oftener than once in ten years will we expose over 10 per cent of
the area. By building side dams to keep certain flats always flowed
this may be reduced to 5 per cent; and this area will be pretty
evenly distributed around 36 miles of uninhabited shore line,
leaving the reservoir open to no valid sanitary objections. On the
contrary, by relieving the remainder of the Passaic Basin of the
flood waters of the Pompton, which now flow large areas of flat
land during wet seasons, the sanitary condition of the valley would
be much improved.
In constructing this reservoir Mr. Vermeule stated that the following
work would be necessary:
The removal of the Delaware, Lackawanna and Western Railroad from
the basin by changing the alignment for 6 miles. It may be done
without increase of length or detriment to the alignment.
Three and one-fourth miles of the Morris Canal must be rebuilt. No
engineering difficulties are involved.
Of the New York and Greenwood Lake Railway, 9 miles would have to
be rebuilt.
The New York, Susquehanna and Western Railroad would be slightly
shifted or raised for 3-3/4 miles.
A dam 2,400 feet long and 80 feet in height, with tunnels,
wasteweir, and accessory works would be required at Mountain View.
The situation is such that an ample wasteweir may be built at a
low-side dam on the solid rock of Hook Mountain remote from the
dam, and outlets may be had by tunneling the same ridge. Hence the
dam may be a plain, heavy earthen embankment; built, of course,
with every precaution but subject to less than the usual dangers of
such works. However, a masonry dam might readily be substituted.
There would be 14,000 acres of arable land, swamps, and rough
mountain land flowed.
The works are estimated to cost as follows:
| Railroad and canal diversions | $505,000 |
| Dam and accessory works | 1,162,000 |
| Land damages | 1,400,000 |
| Total | 3,067,000 |
A recomputation of the drainage area above Mountain View, made by the
northern New Jersey flood commission, shows that it is 380 square miles
in extent. It was decided by this commission that the construction of
this reservoir would be the most approved method of preventing
disastrous floods in the lower valley of the Passaic. By raising a dam
to a height of 202 feet above tide, 8 inches of water on the drainage
area above might be held back, which, it was believed, would be a
sufficient maximum for flood catchment. With this amount of storage the
estimates of the flood commission showed that the remainder of the
drainage area would not turn a sufficient amount of water into the lower
valley channel to cause flood damages.
It was also demonstrated by the flood commission that by increasing the
height of the dam an opportunity would be afforded for conserving water,
and at the maximum height of 220 feet above tide sufficient storage
capacity would be available to provide 5,000 horsepower at Little Falls,
Great Falls, and Dundee dam throughout all dry seasons. The value of
such a storage reservoir for municipal water-supply purposes is
self-evident.
The cost of Mountain View reservoir would be about $3,340,000. Developed
for flood catchment with the spillway of the dam at 202 feet above sea
level the area of the reservoir would be 13.4 square miles, and the
storage capacity 7,200,000,000 cubic feet.
RAMAPO SYSTEM.
Along the Ramapo Valley there are alternative propositions, one of which
involves the construction of a dam below Darlington and another across
the head of Pompton Lake.
In either case the water might be raised to the 300-foot contour, and if
the dam across Pompton Lake were constructed a continuous lake would be
formed extending 10-1/2 miles to Hillburn, N. Y. The improvement in
either case would be positive, for as the country surrounding is hilly
or mountainous it affords excellent opportunity for the location of
summer homes and parks, the lake being a potent factor in beautifying
the situation and increasing the value of the surrounding region. There
are, nevertheless, several things to be taken into consideration, the
most important of which are the improvements which have been made by
wealthy residents along the valley where it has already been developed
as a summer resort.
By the construction of a dam at Darlington 1,100 feet long and 70 feet
high, the water would be raised to the 300-foot contour. The reservoir
would have a water area of 2,064 acres, and the approximate storage
capacity of 2,325,000,000 cubic feet.
A dam across the head of Pompton Lake 2,850 feet long and 100 feet high
would raise the surface of the proposed lake to the 300-foot contour.
This reservoir would have an area of 6.19 square miles and a capacity
of 6,300,000,000 cubic feet, equal to 17.5 inches run-off from the
drainage area. Here the measure of safety is wide, and if there were
drawn from the lake an amount of water equal to 12 inches on the
drainage area there would still be 5.5 inches which could be used for
compensating purposes.
The construction of either one of the above-described reservoirs would
involve interstate complications, as the 300-foot contour in Ramapo
Valley includes a considerable part of the State of New York. This
obstacle was deemed insurmountable by the northern New Jersey flood
commission, and that commission directed studies to a reservoir which at
the time of maximum flood would not back water into New York State to a
greater height than it already rises during such floods. The following
description is taken from the report of the engineering committee of the
flood commission:
An admirable dam site is offered on Ramapo River about 2 miles
above Oakland village. The drainage area tributary to this point is
about 140 square miles in extent, the country for the most part
being quick-spilling and upland. By constructing there a dam 700
feet long and 65 feet high a reservoir with a water surface of 2.8
square miles would be afforded, the flow-line elevation being 280
feet above tide. The capacity of such a reservoir would be
1,768,000,000 cubic feet, equal to about 5.5 inches on the drainage
area.
WANAQUE SYSTEM.
Near the headwaters of Wanaque River is Greenwood Lake, a large body of
water described in Water-Supply Paper No. 88. Its value as a flood
catchment basin is somewhat uncertain, as it is used as a storage feeder
for Morris Canal. The surface level of this lake is controlled by gates,
which naturally are operated by the canal authorities for the benefit of
the canal. Therefore it is the object to store as great a volume of
water as possible, and the water falls below the dam crest at the outlet
of the lake only when the dam opens in dry seasons and makes it
necessary. Under such conditions there is no certainty that storage
capacity will be available during the time of a great storm, and in fact
Greenwood Lake has been overflowing at the commencement of the storms
which caused both of the recent floods.
In view of the condition expressed above it will be necessary in
providing for flood catchment in the Wanaque drainage area to omit
entirely from consideration the possibility of assistance from Greenwood
Lake. Below this point in the basin are several sites at which could be
raised dams, which would effectually retain a large proportion at least
of storm run-off. They may be described as follows:
Midvale reservoir.—By building a dam 60 feet high and 1,200 feet long
across Wanaque River near Midvale, a reservoir would be formed which
would have a water surface of 2.1 square miles and a capacity of
1,491,000,000 cubic feet. The drainage area above this site is 83 square
miles, and the storage capacity would therefore be equal to about 7.7
inches on the drainage area. The construction of this project would
involve the relocation of about 4-1/2 miles of the New York and
Greenwood Lake Railroad; the damages apart from this would be nominal,
the cost of the entire reservoir construction being about $1,000,000.
Ringwood reservoir.—Ringwood Creek runs through a gorge about 1 mile
above its confluence with the Wanaque. Above this is a well-defined
basin. A dam about 70 feet high and 585 feet long would create a lake
having an area of 520 acres, the surface of which would be 380 feet
above sea level. The drainage area tributary to this point has an area
of about 20 square miles, and as the proposed reservoir would have a
capacity of 915,800,000 cubic feet, there could be conserved a run-off
of 20 inches. Allowing for a flood run-off of 12 inches there would
still be available for compensating purposes 8 inches on the basin,
equal to 373,550,000 cubic feet. The construction of this reservoir
would involve the relocation of about 2 miles of the Ringwood branch of
the New York and Greenwood Lake Railroad, and the condemnation of
comparatively valuable improvements in the proposed basin.
West Brook reservoir.—The drainage from 5.7 square miles might be
conserved by the erection of a dam on West Brook, a tributary of Wanaque
River, which enters it from the west. There is an available site at
which a dam 280 feet high might be erected. At this elevation the length
along the top would be about 1,150 feet and about 2,330,000,000 cubic
feet of water would be impounded. Little benefit would be derived from
such a reservoir, as the limited drainage area affords a comparatively
small proportion of flood run-off that might be well cared for at a
lower point. For compensating purposes, however, a reservoir might be
constructed here, the capacity of which could be adjusted to the actual
demands. If the dam were raised to a height of about 280 feet from the
base the storage afforded would be equal to 176 inches on the watershed,
or about four average years of precipitation, which is far beyond all
probable storage necessities. The maximum available storage capacity is
given in this case merely to show possibilities.
PEQUANAC SYSTEM.
There are few available reservoir sites of large size along the lower
reaches of Pequanac River. In the upper basin, however, there is a
sufficient available storage capacity to afford almost complete control
of destructive floods from that part of the drainage area. Large tracts
are already reserved by the city of Newark for collection of municipal
supply, and the storage capacity developed is sufficient to serve the
city throughout the driest seasons. The total capacity of Clinton,
Oakridge, and Canistear reservoirs is about 1,155,000,000 cubic feet.
These basins are not available for flood catchment, as the water is used
for city purposes and an endeavor is made to have in storage at all
times the largest possible amount. The condition is exactly similar to
that described in the case of Greenwood Lake. In considering the means
for the construction of flood-catchment reservoirs in Pequanac Basin
there must be taken into account the conservation and delivery of the
Newark supply. The adjustments with reference to the amount of water
available at Macopin intake would have to be met, and if the system were
interfered with compensation therefore would be taken into
consideration.
Newfoundland reservoir.—Pequanac River passes through a deep gorge
between Copperas and Kanouse mountains, just below the village of
Newfoundland. This point has been considered an excellent site for the
construction of a dam, and in the installation of the present
water-supply system of Newark it is proposed that the entire valley in
which Newfoundland is situated be overflowed. The site is one of the
most advantageous known for the creation of a flood-catchment basin. If
a dam 50 feet high were erected across this gorge, a lake would be
formed which would have a surface area of 3.15 square miles and a
capacity of 3,267,200,000 cubic feet, equal to a storage of about 30.5
inches on the 46.12 square miles of contributing drainage area. This
would afford complete protection in case of a sudden run-off of 12
inches, would provide for the supply of the city of Newark without
greatly disturbing the present storage system of that city, and would
still yield a large amount of water for compensating purposes in dry
seasons.
The construction of Newfoundland reservoir would be very expensive, as
it would involve the flooding of Newfoundland Village, in which there is
considerable improved property. About 3 miles of the track of the New
York, Susquehanna and Western Railroad would be submerged, as well as a
considerable mileage of macadamized highways. On the whole, however, the
Newfoundland reservoir project is the most favorable which can be found
on the Pequanac Basin. There are above this point numerous reservoir
sites, but their combined capacity would not be equal to that of the
proposed Newfoundland reservoir, and the construction would be probably
quite as expensive.
Stickle Pond reservoir.—Below Newfoundland there are few available
places at which water could be stored. Stickle Pond is probably the best
adapted of any of those available. If a dam 1,050 feet long and 80 feet
high were erected across the river about 1 mile below the present outlet
of Stickle Pond, a lake would be formed having a surface area of 422
acres and a storage capacity of about 800,000,000 cubic feet. The
drainage area above this dam would be approximately 4 square miles. This
is a comparatively small amount of storage, yet it would provide for all
flood catchment in that comparatively limited area and would be of
assistance at times in compensating the dry flow of the Pequanac.
ROCKAWAY SYSTEM.
Rockaway River offers a greater number of available reservoir sites than
either of the other highland tributaries of the Passaic. Some of the
reservoirs which could be constructed could be used solely as catchment
areas to hold back flood waters, while the capacity of others would be
so much greater than any single flood run-off that they might serve also
as compensating reservoirs. A large dam is now in process of erection at
Old Boonton, conserving a considerable amount for the water for the
municipal supply of Jersey City. This reservoir can not be depended upon
as a flood-catchment area, as it will be the aim of those in authority
to maintain the water in it as high as possible.
Powerville reservoir.—A short distance above Boonton the erection of
a comparatively small dam would flood a large, irregular, flat basin
having an area of a little more than 4-1/2 square miles and extending up
the Rockaway Valley to Rockaway Village, up Beaver Brook to Beech Glen,
and north and south for considerable distances. The probable capacity of
this reservoir has been estimated, and it is fairly certain that it is
considerably more than would be sufficient for flood catchment. Its
construction would, moreover, improve the entire valley and be of
advantage to many interests.
The northern New Jersey flood commission has selected for investigation
a reservoir site on Rockaway River at Powerville. By the erection of a
dam across the stream at this point, 28 feet in height and 470 feet
long, a reservoir 4.6 square miles in area, with a capacity of
1,565,000,000 cubic feet, would be afforded. The drainage area above
this point is 114 square miles. The cost of such a reservoir is
estimated at $600,000.
North from Powerville, near the confines of the proposed Powerville
reservoir, there is an available reservoir site along Stony Brook. By
the erection of a dam 1,100 feet long and 120 feet high a lake would be
formed 645 acres in extent, which would serve as a flood-catchment basin
and a compensating reservoir. This reservoir would hold approximately
850,000,000 cubic feet. The construction of a reservoir at this place
offers no engineering difficulties, and the project may be regarded as
extremely favorable.
Dixons Pond, west of Rockaway Valley and northwest of Powerville, is a
small sheet of water which lies in a valley which might be flooded to a
greater height. By the erection of a dam 450 feet long and 30 feet high
a lake of 136 acres would be created, which would form a part of the
flood catchment and compensating service.
Longwood Valley reservoir.—A large storage basin is afforded in
Longwood Valley which, if developed to its full extent, would extend
from a point about a mile below Lower Longwood 7 miles up the headwaters
and reach to about 1-1/2 miles above Petersburg. An alternative
proposition is afforded which involves the submerging of less than half
this area.
A dam 800 feet long and 55 feet high might be erected across a gorge
about 1 mile south of Petersburg. There would be formed a lake of about
1.247 square miles, or 800 acres in extent. The hamlet of Petersburg
would be submerged, but the damages from the destruction of improved
property would not be very great, as the improvements and the land are
not especially valuable. This reservoir would have a capacity of about
964,000,000 cubic feet and the surface would be at a height of 800 feet
above sea level.
The alternative plan, that of using a longer stretch of the valley for
reservoir purposes, would involve the construction about 1 mile below
Lower Longwood of a dam 1,300 feet long and 110 feet high. The reservoir
thus formed would be 1,900 acres in extent and contain approximately
3,447,000,000 cubic feet. The drainage area above this dam is limited,
and if the reservoir were drawn down to an amount equivalent to 15
inches upon the drainage area there would still remain an enormous
amount of water which could be used in a compensatory way to tide over
dry seasons.
Splitrock Pond.—By erecting a dam 550 feet long and 30 feet high
across a gorge at the outlet of Splitrock Pond, a lake could be formed
having an area of 625 acres and adding to the present storage capacity
of the lake an amount approximately equal to 475,000,000 cubic feet,
equivalent to 38.75 inches on the drainage area.
Thus it is seen that if this reservoir were drawn down an amount
equivalent to 15 inches on the drainage area, which would without doubt
give sufficient protection from all floods, there would still remain a
storage capacity of 23.75 inches for compensating purposes in addition
to the amount now available in Splitrock Pond. This project is one of
the most attractive in the Rockaway Basin, as the damages which would be
caused by flooding would be, comparatively speaking, nil. The property
is, however, now owned by the East Jersey Water Company, and is prized
highly as a reservoir site by that corporation.
UPPER PASSAIC BASIN.
Millington reservoir.—There is an area of swamp land, comprising a
part of the drainage area of upper Passaic River above Millington, which
is known as Great Passaic Swamp. It is bounded on the south by a long,
narrow trap ridge known as Long Hill, the summit of which ranges from
400 to 500 feet in elevation, or roughly 200 feet above the border of
this swamp. To the northwest the land rises gradually toward Trowbridge
Mountains, while to the northeast is the terminal moraine. The outlet of
Passaic River at Millington is by a narrow gorge, which offers natural
facilities for the erection of a dam.
The whole situation is exceptionally good, and the surface of a
reservoir might be fixed at any elevation between 240 and 300 feet above
sea level. With the surface of the reservoir at 300 feet a dam 1,600
feet long and 90 feet high would be required. This lake would have an
area of 28.46 square miles. The drainage area above Millington has,
however, an area of only 53.6 square miles, and the proposed reservoir
would therefore cover more than half of this. Therefore the conservation
of so large a quantity of water would not be necessary nor advisable,
unless the beautifying of the surrounding country were an object to be
taken into consideration, which might be profitable.
A better project, however, would be to construct a dam at Millington 900
feet long and 50 feet high, the crest being about 260 feet above sea
level. There would be formed a lake with an area of 19.41 square miles,
and a capacity of 1,477,600,000 cubic feet, equal to 9.864 feet on the
drainage area. This project is too great for the necessities here
presented, and would not be wisely considered unless it were found
advantageous to improve the country generally as a place of suburban
residence. The land which would be flooded with the reservoir crest at
260 feet is of a wet, swampy character, and its value for agricultural
purposes is somewhat doubtful. Such construction would involve the
flooding of 13 miles of road, which, however, would not involve a great
loss of invested capital, as the roads generally are of a poor
character.
A second alternative would involve the construction of a dam across the
Millington gorge, 550 feet long and 30 feet high, raising the water to
240 feet above sea level and creating a lake of 14.40 square miles. This
would conserve 4,026,000,000 cubic feet, equal to 2.69 feet on the
drainage area. This would be ample for flood purposes and would still
afford a large impounded area, as the drawing off of an amount equal to
10 or even 15 inches on the watershed would not reduce the size of the
lake to any great extent.
The whole project here presented involves few difficulties, and as the
drainage area above is of small extent, the mere question of conserving
the flood waters could be met without great difficulty. The natural
advantages, however, are so great and the land included within Great
Passaic Swamp is of so little value that the surrounding country would
be improved and beautified by the construction of such a reservoir. The
opportunity for varying the character of the reservoir to meet the ideas
of those interested seems unexampled, and as a whole it presents an
extremely interesting field which may be profitably exploited.
SADDLE RIVER.
This stream has been described in the report on the flood of 1902,
already referred to. It contributes a large amount of water to the main
artery of the Passaic below Dundee dam, and as the river channel at that
point is overburdened under the present conditions because of lack of
slope and numerous catchments, together with what is known as the
Wallington Bend, it increases very materially the damage caused by
floods.
The most effectual remedy in the case of Saddle River floods is that of
construction of flood catchments. No studies have been made of the
situation in the Saddle River drainage area, but a superficial
inspection of the basin shows that opportunities for the construction of
flood-catchment reservoirs are not numerous.
SUMMARY OF FLOOD-CATCHMENT PROJECTS.
By following the plans described in the preceding pages absolute flood
catchments may be provided above Little Falls on the Passaic Basin for
551.7 square miles, leaving only 221.2 square miles from which flood
run-off would flow immediately. The accomplishment of this would involve
the construction of Pompton reservoir, which would withhold all flood
waters from the northern tributaries. It would leave unprovided for 20.2
square miles on the Rockaway, 71.7 square miles on the Whippany, 46.2
square miles on the upper Passaic, and 83.7 square miles tributary to
the Central Basin and not included above.
Leaving Pompton reservoir out of consideration, and conserving flood
run-off on the Ramapo, Wanaque, and Pequanac rivers, there would be
absolute flood catchment up to a 12-inch run-off over 494.8 square miles
above Little Falls. This would leave 278.1 square miles unprovided for,
the run-off from which would not overburden the channel in the lower
valley, provided, of course, that channel were improved to a maximum
carrying capacity.
PREFERABLE RESERVOIR SITES.
The following table and discussion of preferable sites for flood
prevention are taken from the report of the engineering committee of the
northern New Jersey flood commission:
Table showing detailed facts regarding possible reservoir sites on
Passaic drainage basin.
| Reservoir. | Area of watershed. | Area of reservoir. | Height of dam. | Length of dam. | Elevation of flow line. | Storage, watershed. | Storage capacity. | Total cost. |
| | Sq. mi. | Sq. mi. | Feet. | Feet. | Feet. | Inches. | Million c.f. | |
| Ramapo | 140 | 2.8 | 65 | 1,700 | 280 | 5.5 | 1,768 | $900,000 |
| Wanaque | 83 | 2.1 | 60 | 1,200 | 275 | 7.7 | 1,491 | 1,000,000 |
| Newfoundland | 52 | 1.8 | 40 | 430 | 780 | 8 | 966 | 1,800,000 |
| Rockaway | 114 | 4.6 | 28 | 470 | 520 | 6 | 1,565 | 600,000 |
| Millington | 56 | 15.8 | 25 | 220 | 245 | 31 | 4,060 | 370,000 |
| Great Piece | 773 | 37 | 21 | 1,500 | 178.5 | [C]9 | 8,950 | 2,625,000 |
| Mountain View | 380 | 13.4 | 42 | 2,150 | 202 | 8 | 7,200 | 3,340,000 |
| Do..... | 380 | 13.9 | 44 | 2,380 | 204 | 9 | 7,900 | 3,460,000 |
| Do..... | 380 | 14.3 | 46 | 2,470 | 206 | 10 | 8,700 | 3,590,000 |
| Do..... | 380 | 17.4 | 60 | 3,000 | 220 | 17 | 15,000 | 5,260,000 |
With the exception of the Millington reservoir site where the cost
of the dam is a small factor, the elevation of flow line in the
various reservoirs which determines the capacity was fixed so as to
afford an approximate storage equal to a run-off of about 8 inches
from the drainage area above each dam site. This amount is somewhat
in excess of the run-off for the flood of October, 1903. It was
found impracticable on the Rockaway reservoir site to provide for a
storage greater than 6 inches. On the Wanaque the amount which can
be stored falls slightly under 8 inches, while on the Ramapo it is
possible to obtain only 5-1/2 inches, by reason of the fact that
with a greater storage capacity the slack water would reach into
New York State. The economical height for a dam at the lower end of
the Great Piece Meadow, if such dam is provided with fixed
discharge openings which will carry a maximum outflow of 12,000
cubic feet per second, will provide a reservoir which will dispose
of a run-off of 9 inches on the drainage area above.
The following combinations of reservoir sites, with their
respective drainage areas, proportional storage, and estimated
costs, give the facts necessary for final deductions:
| Site. | Drainage area. | Water collected. | Equivalent area retarded. | Cost. |
| | Square miles. | Inches. | Square miles. | |
| Ramapo | 140 | 5.5 | 96.25 | $900,000 |
| Wanaque | 83 | 7.7 | 80 | 1,000,000 |
| Pequanac | 52 | 8 | 52 | 1,800,000 |
| Rockaway | 114 | 6 | 85.5 | 600,000 |
| Total | 389 | ..... | 313.75 | 4,300,000 |
| Ramapo | 140 | 5.5 | 96.25 | 900,000 |
| Wanaque | 83 | 7.7 | 80 | 1,000,000 |
| Rockaway | 114 | 6 | 85.5 | 600,000 |
| Millington | 56 | 31 | 56 | 370,000 |
| Total | 393 | ..... | 317.75 | 3,870,000 |
| Great Piece | 773 | 4.5 | 435 | 2,625,000 |
| Mountain View | 380 | 8 | 380 | 3,340,000 |
The necessity to retard the flow of or provide storage for
approximately 380 square miles of highland drainage area has been
determined after careful study, and there has been deduced an
amount which may safely be expected to represent the maximum for
the highest floods. When the highland tributaries are sufficiently
checked the natural storage on Great Piece Meadow in its effect
upon flood control becomes more apparent. Our investigations show
that the holding back of the flood flow—that is, 8 inches run-off
on approximately 380 square miles of flashy drainage area above
Great Piece Meadow—is necessary to reduce the discharge in the
river through the city of Paterson to 14,000 cubic feet per second
for a flood similar to that of 1903.
From the foregoing table, in which different reservoir projects are
compared, it is seen that only the reservoirs designated as Great
Piece and Mountain View will fulfill the requirements within a
reasonable limit of cost. It is also shown that a combination of
any other available sites would involve the expenditure of more
money for their construction and the control of less tributary
drainage area than is fulfilled by the demands of the Passaic
drainage basin. We are therefore brought to the conclusion that
only two of the projects above set forth will be effective. First,
the construction of a regulating dam on the main stream above
Little Falls, which we have called the "Great Piece" Meadow
Reservoir, and second, the building of a dam at Mountain View
across Pompton River. The relative cost of these reservoirs,
constructed for flood control exclusively, is $2,625,000 for that
on Great Piece Meadow and $3,340,000 for the Mountain View site.
Details of these estimates are as follows:
Estimate of cost of Great Piece Reservoir, dam at Little Falls.
[Elevation of flow line, 178.5 feet. Storage and disposal of 9 inches
collected.[D]]
| Earth excavation, 17,600 cubic yards, at 35 cents | $6,160 |
| Rock excavation, 8,800 cubic yards, at $2 | 17,600 |
| Rubble masonry, 29,100 cubic yards, at $5 | 145,500 |
| Ashlar masonry, 1,800 cubic yards, at $12 | 21,600 |
| Facework of rubble masonry, 2,850 square yards, at $1.50 | 4,275 |
| Concrete masonry, 250 cubic yards, at $6 | 1,500 |
| Slope paving, 300 cubic yards, at $2 | 600 |
| 60-inch cast-iron pipe in place, 360 tons, at $35 | 12,600 |
Relocation of railroads, Erie, 5 miles, at $20,000; Delaware, Lackawanna
and Western, 4.5 miles, at $40,000 | 280,000 |
| Relocation of highways | 170,000 |
| Real estate: | |
| Above Mountain View | 500,000 |
| Additional for village of Singac | 100,000 |
| 22,000 acres, at $50 | 1,100,000 |
| | 2,360,000 |
| Add for engineering and contingencies | 240,000 |
| | 2,600,000 |
| Protection of pipe lines, Newark and Jersey City | 25,000 |
| | 2,625,000 |
The effectiveness of a reservoir built upon the lines proposed in
the case of Great Piece Meadow depends upon the adjustment of
outflow so that the channel below will not be overborne, while at
the same time sufficient storage capacity is afforded to hold
temporarily the water which enters above the dam in amount greater
than the carrying capacity of the outflow apertures. The dam across
Passaic River above Little Falls would be provided with apertures
which would discharge 12,000 cubic feet per second under the
maximum head in the storage basin. As the flood rises these
apertures would discharge a constantly increasing amount of water
to the maximum, and for a considerable time thereafter the maximum
would be maintained, the discharge decreasing after the flood
according to the height of water remaining in the reservoir.
Estimated cost of Mountain View Reservoir.
[Elevation of flow line, 202 feet. Storage of 8 inches on watershed.]
| Earth excavation: | |
| Stripping dam base, 83,500 cubic yards, at $0.30 | $25,050 |
| Core wall trench, 24,900 cubic yards, at $1 | 24,900 |
| Rock excavation, 10,100 cubic yards, at $2 | 20,200 |
| Rock fill in dam, 197,000 cubic yards, at $1.25 | 246,250 |
| Rubble masonry, 23,200 cubic yards, at $5 | 116,000 |
| Concrete, 30,000 cubic yards, at $6 | 180,000 |
| Gate chambers and tunnels | 65,000 |
| Reconstruction of highways | 142,400 |
| Reconstruction of railroads | 815,000 |
| Real estate | 1,360,000 |
| | 94,800 |
| Engineering and contingencies | 325,200 |
| | 3,320,000 |
| Protection of Newark pipe line | 20,000 |
| Total cost | 3,340,000 |
| |
| [Same for elevation of flow line, 204 feet. Storage of 9 inches on watershed.] |
| |
| Earth excavation: | |
| Stripping dam base, 85,200 cubic yards, at $0.30 | $25,560 |
| Core wall trench, 26,000 cubic yards, at $1 | 26,000 |
| Rock excavation, 10,600 cubic yards, at $2 | 21,200 |
| Rock fill in dam, 214,000 cubic yards, at $1.25 | 267,500 |
| Rubble masonry, 24,500 cubic yards, at $5 | 122,500 |
| Concrete, 30,500 cubic yards, at $6 | 183,000 |
| Gate chambers and tunnels | 65,000 |
| Reconstruction of highways | 142,400 |
| Reconstruction of railroads | 815,000 |
| Real estate | 1,435,000 |
| | 3,103,160 |
| Engineering and contingencies | 336,840 |
| | 3,440,000 |
| Protection of Newark pipe line | 20,000 |
| Total cost | 3,460,000 |
The final recommendation of the committee involves the
consideration of two projects for flood storage, one on Great Piece
Meadow and the other above Mountain View on the Pompton. In making
such recommendations the committee is of the opinion that it must
take into account matters of engineering policy with regard to
future needs and contingencies, as well as the bare necessities of
the present.
If there were none other than the single problem of prevention the
committee would advise the construction of the reservoir on Great
Piece Meadow by reason of its smaller probable cost and its equal
efficiency. It is plain, however, that there are many important
features of public policy involved in the subject at hand.
Population in the valley of the Passaic is developing so rapidly
that in only a few years the present sources of water supply will
be inadequate. The whole subject of water supply for northern New
Jersey demands immediate consideration, and it would not be wise to
take up the matter of prevention of flood damage in the Passaic
without basing the value of every project upon its adaptability
for use in future water-supply needs.
By expending $2,600,000 a great reservoir could be constructed upon
Great Piece Meadow which could not be adapted for any purposes
except to regulate floods; it would stand in season and out of
season a huge feature of the valley and entirely useless and
inoperative save on the occasion of high water. However great might
be the needs of the inhabitants of the Passaic Valley for a
conserved water supply, the construction on the meadows,
representing an enormous expenditure, would furnish no solution of
the problem. It would admit of no enlargement for water-supply
storage and would be available for no purpose except flood
regulation.
When we consider the Mountain View project, however, we find that
as a measure for the prevention of flood damages it fulfills all
the requirements and provides in addition all the possibilities and
advantages demanded inevitably in the near future. The Mountain
View site is an ideal one for the reservoir, and its initial
development for flood catchment does not involve the expenditure of
a dollar that would be lost in the development of the basin to
greater capacities for water supply. From its lowest level, at 202
feet above tide, to its maximum capacity, at a level of 220, there
would be no depreciation. Every dollar spent in the initial
construction would be effective in the maximum development.
The probable cost of Mountain View reservoir, estimated at
$3,340,000, exceeds that of Great Piece by $700,000. It is realized
that to many persons this margin may seem very wide. Let us
consider briefly just what it really represents.
Suppose, for example, that the Great Piece project is constructed
at a cost of $2,600,000. After the elapse of a few years it will be
necessary to provide additional storage in the Passaic highlands
for water supply or the maintenance of water power. The Mountain
View reservoir, or its equivalent in capacity and cost, will then
be necessary. The situation will then be as follows: By
constructing the Great Piece reservoir in preference to the
Mountain View for flood catchment, $700,000 would be saved. We can
consider that this amount might be expended to pay a part of the
cost of additional conservation above referred to. If, on the other
hand, Mountain View had been constructed, there would have been
paid on the final cost of conservance the sum of $3,340,000, which,
as stated in previous pages, would also have effected flood relief.
There would then be the difference between $2,600,000 and $700,000,
or $1,900,000, which represents the actual loss which would accrue
by reason of the construction of Great Piece reservoir.
The engineering committee, after presenting the merits of both
Great Piece Meadow and Mountain View projects, therefore recommends
the adoption of the latter in spite of its greater cost, because it
is believed that in the end the construction of the Great Piece
project would involve an expenditure not warranted by public
economy or general expediency.