WATER POWER OF CARATUNK FALLS, KENNEBEC RIVER. ME.*
IN the winter of 1888-89 I made an examination of this power, on the Kennebec River, Me., for some Boston capitalists, and, incidentally, of tbe power capacity of the river at, and above Augusta.
Water power being determined in the main by drainage area, rainfall, climate, relative storage, and local fall, from very careful statistics and examinations at command I found the following conditions.
CATCHMENT Basin.—The basin of the Kennebec is compact in form hold in contours, abounds in lakes and forests, hag a heavy and quite regular rainfall, a cold climate, favorable to its stream-flow, and is capable of large development In power. The length of the river, from its headwaters of the Moose to Hoosehead lake is 72 miles; to Caratunk Falls, 187 miles; to Augusta, 1H4 miles; to the ocean, 227. It divides in the White Mountains rise to 8,113 feet above tide, —Moosehead lake being 1,023 feet, Caratunk Falls, 3Hi feet; Kkowhegan, 220 feet; Kendall’s mills, 76 feet; Augusta dam, 17 feet above tide. The formation of the upper basin is granite, sandstone, and slate; thence to the ocean, mica schist, clay, slate, and gneiss, as at Caratunk Falls. The river basin is about 5,917 square miles. About 8,800 square miles arc in forest.†
There are 811 lakes and ponds, somewhat more (311 to 290) than the mean lake distribution In the state; joint area, 400 square miles; area of 152,857.15 square miles; area of Moosehead lake, 120 square miles; its basin, 616.6, The mean temperature of the northern third of the state is 88 degrees .55 (Falir.); of the southern two-thirds, 48° ,21. mean summer heat, 01°. to 68° .80; mean winter heat, 19°, .00. As a consequence, while there are a large snowfall and deposit, its under stratum thaw maintains winter stream flow, while spring freshets are delayed until the ice, as a rule, is brittle, and does not make the dangerous freshets of milder climates. As will he noticed in its place, upper pond ice sheets strongly tend to prevent sludge ice,and maintain full power head on the daniB.
POWER CONDITIONS. Caratunk is one of those places where nature seems to have adapted her work to a future art UBe. From a comparatively broad river, for several miles, a very narrow gauge compresses the whole flow into a cascade with a natural fall of about twenty-eight feet, while immediately below the river at once widens into still broader expanse for several miles. There are here, then, a large natural pondage above tbe falls, a site already formed for race, wheel-pit, and mills, a powerful fall on this immediate site, and an estuary directly obviating obstructions from flood backwater.
*Read at the aixteenth annual meeting of the American Society of Mechanical Engineers, held in New York, December, 1S95.
*In 11a miles to tide the descent is i*oa feet; about 9.1 per mile; a greater fall in a shorter distance than any other Maine river.
Area.—As outlined on the annexed map (Fig. 1), Caratunk Falls drains four great tributaries—tbe Moose river, 700 55 square miles; Dead river, 887.93 Moosehead lake, 616.60; Kennebec river 578,92 — total, 2,850 square miles.
The tributaries to the Augusta dam, below tbe Falls, are tbe Carabosset, 366 square miles; Wesserunsett, 167; Bandy, 660; Sebasticook, 1,088—total 2,287 square miles.
Raineaix.—From statistics collected by Henry Richards, Ksq., at Gardiner, at tbe lower end of the river, the mean fall for 50 years—1839 to 1888 inclusive—is 44.494 inches. The quarterly seasons’ subdivisions show the usual uniformity: spring, 11,194 inches; summer, 10.550; autumn, 10,500; winter, 12,250. The maximum fall in 1887, 54.64 inches; minimum, 1860, 33.71.
POWER Investment.—Without time to make a continuous guage of the river, it was necessary to estimate its ordinary merchantable value at this point from a study of its hydrology. With twenty-eight feet available floodfall (wheel heads being usually reduced in freshets from hack water), and a mean rain of 44.494 inches, minimum, 38.71 inches, on such a basin, a safe, present plant outlay for 5,000 horse power was determined from experience on this and other rivers.
There is sometimes a conservative and proper, anil sometimes an “intensely scientific” tendency to disparage streams flow for city supply and power use, because in every season there is a short time of extreme minimum flow, and at intervals a year of much reduced flow. A basin, with a rain supply of 45 inches per year, or a mean of 3.815 cubic feet per second per day, may fora few days run as low as 0.22 cubic feet, the Kennebec sometimes down to 0.6 cubic feet, for twenty to twentyfive days; the Merrimac, 0.31 cubic feet; Delaware, 0.30 cubic feet; Passaic, 0.22 cubic feet; Croton, 0.15 cubic feet.. So the rainfall—with a mean for fifty years—on the Kennebec may vary from 54.04 inches, 1887, to 33.71 inches, 1890; but the mean of all the great basins shows these as exceptional years, with large flood waste in the wet months; which dictates the common sense of catchment and storage.
Authorities, like Professor Trowbridge, in “Water-powers of the United States”, p.8, assert that the “total amount discharged by streams falls as low us 12 (0.885 cubic feet per second per square mile) or 15 inches (1.1 cubic feet) over the entire drainage basin, at intervals of from five to ten years.” Nothing can be clearer than the wisdom of adequate provision for exceptional years and weeks; but very great loss of mean available supply and power would follow the reduction of plant to extreme cases.
Merrimac River.—A carefully but not fully developed power like that of Lowell or Lawrence, furnishes a valuable lesson.
At Lowell, with 4,085 square miles basin, with a mean of 44.89 inches rain, nineteen to twenty-seven years, an actual sale of standard power, on 33 feet extreme lowwater fall, is about 3,596 cubic feet per second, or 0.8803 per square mile, for the usual working day of eleven and one-half hours.
At Lawrence, with 4,553 square miles basin, the standard use is 4,200 cubic feet per second for the working day, the full day supply being a mean of about 2,400 cubic feet, or 0.5271 cubic feet per square mile persecond, or 15.85 per cent, of the mean rainfall. Kxtra powers arc largely furnished.
But the stream-flow itself far exceeds this use, with rare cases below standard mill day supply; in six years no month below 2,400 eubic feet per day.
Dry month daily averages at Lawrence, in cubic feet per second are as in the accompanying table :
For the storage control of daily supply, ample provision exists at each point; for that of minimum flow t here is ample and expensive provision, in seven storage lakes of 103.48 square miles area, capacity of reserve, 7,483,283,544 cubic feet on depths of two to four feet; but, while their existence doubtless regulates the river, their full use appears to lie hampered by mills below them, so that practically little special use has been made of them. During these years—eleven months in ail—quantities 39 to 123 cubic feet per second—in one case, September, 1873, 277 cubic feet persecond (Sudbury river case).
In these dry months the mean flow is 6,568 cubic feet per second, 1,442 cubic feet per square mile, 43.6 per cent, of the mean rainfall for these years. How much was wasted in the wet months is self-evident.
The Sudbury liver, a contiguous basin, in five years, 1875-79, with about seventy-eight square miles area, with a maximum rain of 57.93 inches, minimum, 41.42, mean, 47.68, gave actual measured flow of 49.94 per cent., mean, 57.9 per cent., maximum, 44.88, minimum.
The Mystic also in four years, 1876-79, maximum rain, 54.06, minimum, 35.3, mean, 44,86, gave 48.1 per cent., mean, 51.2 per cent, maximum, and 43.6 per cent, minimum.
The Croton in geology and topography better resembles the Kennebec. Its basin of 838.82 square miles above the Croton dam, had a mean rain for twelve years, 1868-77, of 45.98 inches. Measured flow of Boyd’s Corner dam, mean, 57.68 per cent.; lowest, 45 per cent, of 48.93 inches fall; highest, 74 percent, of 50.33 inches.
The mean annual flow of the Connecticut is 1.86 cubic feet per square mile per second; Raritan, 1.22 cubic feet per square mile per second; Potomac, 1.85 cubic feet per square mile per second.
KENNEBEC Power.—Applying these conditions, the relative value of the Augusta and Caratunk dams may be examined.
Augusta dam is 956 feet long, 5vith a fall of seventeen feet. It has a log chute on the east end and a large mill on the west end, of 3,000 horse power. The measurements for low water show a mean in 1866,with 45.63 inches rain, of 2,916.6 cubic feet per second, or 0.494 cubic feet per mile for July, August, and September.
I learned from an intelligent gate-honsc keeper of long experience here, that in the lowest summer run of twenty to twenty-five days (common on other streams) the depth on the dam is about six inches, and the usual depth a foot, for the balance of the dry season, of about 80 to 90 days in all, before and after this reduction; and it was reported as exceedingly rare to have no flow on the dam. With 3,000 horse power in use, six inches flow equals 0.19 cubic feet persecond per square mile, and the mill use, at 70 per cent, duty, is 0.4056 cubic foot, or a total of 0.5956 cubic foot per second. The usual use at Lawrence, very near stream low run, is 0.5271 cubic foot per second per square mile per day. A very low run August 21-26, 1876, gave 0.5 per eubic foot.
The extreme low run assumed by state authorities (W. P. Maine p.92) is 1,300 cubic feet persecond, or 0.22cubic feet per second per square mile. Applying this to the extreme year of 1860, the equation stands: 25 days, at 0 22 cubic feet, 5.50; 60 days, at 0.456 per. cubic feet, 27.36; 280 days (50 per cent, flow) at 1.2415 cubic feet), 347.62; tc tal days, 365; total cubic feet, 380.48; per day 1,042 cubic feet per second per square mile.
At one foot flow (neglecting the waste at the log chute), the dam gives 0.538 cubic feet, and, with the mill, 0.943 cubic feet per second per square mile.
The spring flood-flow has been measured at 35,352 cubic feet per second for five feet depth on the dam, or 6 cubic feet per second per square mile. Other occasional floods have reached 7.1 and in one case 11.5 cubic feet. In these cases the flow is spasmodic, with a rapid risd fjr about twelve hours, a stand of twelve, and a rapid fall.
The streams which supply this dam differ essentially in regimen. Those, like the Carabassett and Sandy, draining the 3.067 square miles below Caratunk Falls, are not well reservoired by natural lakes, and are subject to rapid riseand fall in heavy rains, while the basin above the falls abound in such reservoirs, which greatly reduce floodwaste and improve summer flow.
CARATUNK Power.—In applying these observations to this fall, it is evident that its power conditions aie much more than Augusta below it, or the Merrimac at Lawrence. To analyse the supply as to its capacity and as to its moderate mercantile value, basing one on the mean annual rain of fifty years, 1839 to 1888, and the other on the lowest reconi year, 1860, the following tables have been compiled.
In the tables the relative monthly flow is assumed on percentages derived by other stream analyses, as proximate guides to an estimate of the deficit to be supplied to maintain a given power. In Table I., 50 per cent, flow (1.638 cubic feet per second per square mile, maintained, would give wheels of 70 per cent, duty a moderate estimate for those actually used) for twenty-four hours’ use for full-dav pulp mills, 10,374 horse power, and make a storage draught of 34,509,935,750 for live months, with a large surplus for five months, especially in November and December previous to the deficit of January and Febru-
Table II., for the minimum year of 1860, in like manner. for 60 per cent, flow, or 1,492 cubic feet per second per square mile, 9,450 horse power, shows a deficit for six months of 37,493,979,840 cubic feet, and a balance of 13,573 973 928 cubic feet, or nearly one-third the present jiondage which is 37,794 189,312 cubic feet. For 0.964 cubic foot per second, or 6,000 horse power the deficit for five months is 16,203,104,480 cubic feet, about one-third the surplus above this wheel use for seven months.
STORAGE ltoERVE.-Above the Falls there are fiftyeight important lakes of 229.6 square miles area. Their draught capacity is: 128 square miles, 8 feet (Moosehead lake); 9 square miles, 6 feet; 4 square miles, 4 feet; 32 square miles, 2 feet; 31 square miles (Moose river). 4 feet; 25 square miles (Dead river), 3 feet-total, square miles, 229; total feet, equated depth, 5.92. Total available, 37,794,189, 312 cubic feet.
For logging use Moosehead lake will raise the river at Caratunk Falls four or five feet, as used. Moosehead lake gates are closed in the late fall to store the winter flow at a time when the remaining basin is amply supplied, Evidently then, without special control from Caratunk, very valuable provision already exists to maintain equable flow when most needed; but, as the lumber fails and less spring and early summer use is made for river flushing, the great Moosehead lake will become more available for dry summer supply and raise the value of this power in proportion.
PRESENT Value.—With equal rainfall better conserved by climate and location and with five-fold the proportionate storage reserve of the Merrimac, in a case where it seems to be little needed, from limited wheel use, this fall ought to command much greater supply in dry seasons, It was evident, then, not only that this fall had a great prospective value which will place it in the front rank of great powers, hut a present value, easily and cheaply developed, of not less than 5,000 horse power as a moderate result for full power operation
SWE ADVANTAGES -The rock gorge here at. and below the site of the dam has unusual adaptation to cheap and strong dam, mill, and wheel-pit construction, and easy control of log chute and flood-wash by permanent masonry, while the formation on the East Side is well adapted to store yards, employes’ residences, and other structures The completion of the Somerset railroad to, and across the Falls relieved any question of easy and cheap receipt of machinery or supplies or delivery of products.
Improvements.—In the fall and winter of 1890-91, a dam was built by the Moosehead Pulp and Paper Company, under the superintendence of I). T. Mills, II. E., with a large pulp mill on the west side of the Falls, intended to develop about8,500 horse power on that side. Three “New American” wheels of 850 horse power each have been putin, 66-iuch diameter; one “Special,” 45-incli, 390horse power; a 10-inch “Electric,” of 42 horse-power; and a pair of 13 inch horizontal for a centrifugal pump of 80 horse power, representing about 3,000 horse power. Measurements made through 1890, a very dry year, show a minimum How of 6,000 horse power (on 70 per cent, wheels), as reported to me.
As a practical comment on the cost of steam power, the “Central Pacific” mill at Lawrence, with twenty-nine mill powers, or 1,740 horse power in ordinary use, and without 1,000 horse power steam plant, has preferred to pay $12 per day per mill power for surplus water, for months together, rather than run this expensive plant. This is about $50.40 per horse power per year of 277 days,
The usual Lowell estimate of steam power is $75 per horse power per year, and $3 per week is the common price paid for it in New York and other cities where rented. The Lowell rental of water power at $1,200 per mill power per year is for 277 days, $4.32 per day, or a mean of $20 per horse power (shaft) per year.
NIAGARA WATER POWER.-AS a prominent instance of the superior economy of water power in favorable locali ties, with economically constructed plant, the rates published for the New Hydraulic tunnel are, for 5.000 horse power or over, $10 per horse power peryear; 4,500, $10.50; $11; down to small powers, 800, $21. On the old Hydraulic canal powers have been based as low as $4 for …-…600 to 1,600 horse power, and $5.80 for 250 to 300. It is now proposed to furnish Buffalo with power at about $1*. which now costs at least $50 for steam.
COMMERCIAL Value.—Lowell, with 40,085 square miles basin,worth, properly reservoired, at 50 per cent.. ,7,112 cuhie feet per second, actually has sold and maintained as regular power, 139.86 mill power,about 11.141 horsepower “penstock,” and 8,363 “shaft,” for which the rental value is about $1,200 per year per mill power, or at 6 per cent, $20,000 capital, or $2,787,200. In addition, there is a large sale of extra powers.
Lawrence, with 4,553 square miles basin, worth about 9,000cubic feet per second, uses about 2,400 cubic feet (twenty-four hours mean), and with 1H0.mll powers now controled, has maintained and sold 122, about 7,320 horse power “shaft,” worth, at.6 per cent, capital, $2,244,000 and has also sold an average of about twenty extra powers, about seven months’ use, payment, $1,280(or about $2,194 per year), or $21,836 at 6 percent.; value, $731,540; m all, $2,866,720. In addition, there is a land increase which $2,886,729. in adcm.on, mere is a makes the value of these powers about $.15,000 to $40,000 each. Controling 180 mill powers,of 50 cubic feet per second, or a mean per day of 2.700 cubic feet, with a rainfall of 15,050, it can actually sell 18 per cent, of this mean supply on the entire basin without careful flood storage.
ANCHOR Ice.-In the second of the four modes of watermotion, in which the particles move with the wave, in channel flow, there is a constant motion from the surface towards the bottom, proximating a cycloid curve, described by apointon the tire of a carriage wheel in motion. In very cold weather theeffect is to reduce the surface patticlesmore or less below freezing temperature, and, coming in contact with iron bars, valves, etc., a rapid accountlation of needle ice takes place when the stream surface near them is thus exposed, but when the current for some distance is protected from the air, the temperature is kept above freezing, and this action prevented. On sees in the races above the mills in Maine several hundred feet of floating, light, wood frames, intended to promote ice-formation and prevent this surface motion exposure^
At Caratunk Falls, the reach above the dam freezes for two miles up stream, with blue ice twenty-four inches thick in winter; above this the stream is obstructed by this anchor ice, as it is below the falls, with an open stream; but this ice sheet effectually prevents it, and this suggests a valuable remedy for a very serious trouble on various rivers and races,
TIRHINES. — The “centre vent” or “inward flow” wheel, with its carefully planned and adjusted curbs, and gates, has been the favorite of its class, originating in the ” Wry Fly,” of Benjamin Tyler, of 1804. Those of the “New American” type use here have shown high duty especially in “ part gate” work.
Tests at Holyoke, July 8, 1894, show results indicated as follows:
Relative Cost; Steam and Water Power.—Estimates for of steam substitution arc necessary in mill power excascs much difference of opinion is sometimes expressed. Like all other engineering questions this is to determined by the principles involved, in which specdiffer, without affecting the general Obviously, power generated by the great steam globe itself, by which enormous bodies of precipitated on the earth, to seek sea-level unQCI* der the influence Ol of gravity, with WHU II a weight of cubic foot, is cheaper than ordinary steam-enginepower. There is also a material difference in plant cost between between an an 850 850 liorse-power horse-power turbine turbine fitted fitted in in place place an engine plant in n place. place. There There is is also also attendance, wear, and oilier rontingeneieK, ontingcncicH, insurance, insurance, etc.,a material ‘ * difference.
if, then, the location and supply admit an economical application of power, all these conditions favor water* power. In tins case the outlay for dam, flume, hend gates, wheel-pit, etc., was about $15 per horse power of 3.000 i actually provided on the west side; the cost of wheels, for 3,000 horse power, about $9, or $24 in all. Similar steam plant could not be furnished for less than $65 per horsepower. for boiler, engines, and buildings. A fair estimate of its annual fixed expense Is: Depreciation, 4 per cent.; repairs, 4 per cent.; supervision, 1 per cent.; taxes, 12 per cent.; Insurance, 1 1-3 per cent.: Interest, 5 per cent.; total 18 per cent, on $65, $10.40.
Annual operation for 8,000 horse power, 300 full days per year (pulp mill),closely estimated:
This This shows, shows, in in a a local local case case like like this, this, a a proximate proximate CM comCotton and similar mills, unlike pulp mills, reheating, have in steam plant the useof ex* ways local cases will modify than the superior economy of water power perse.
T he flames arising from a lot oHeaves and rubbish that had been set on fire in t a.rmount Park hiUdelphia.near the Queen Lane reservo.r threatened to burn a rame shanty m which was stored a ot of dynamite. A chemical engine failing to extinguish the blaze, the firemen were obliged to attach a hose to a hydrant more than 300 yards from the fire to get water to put tt out.