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should not be made to suffer from the proposed improvements. The State has chartered a company that brings these logs down the river and rafts them only after passing Augusta. At the place known as Pettys Rips the channel is narrow, and it is sometimes filled with logs for days at a time.

I am informed that the lock at Augusta is not of sufficient length for the class of boats that would go up to Waterville. To lengthen it so that it would meet the requirements would add $25,000 to the estimated cost of the improvement, making the total $70,800.

I inclose herewith two tracings* showing the survey.
Very respectfully, your obedient servant,

PETER C. HAINS,

Lieutenant-Colonel, Corps of Engineers.

Brig. Gen. THOMAS L. CASEY,

Chief of Engineers, U. S. A.

REPORT OF MR. F. S. BURROWES, ASSISTANT ENGINEER.

UNITED STATES ENGINEER OFFICE,

Portland, Me., January 6, 1892.

COLONEL: I have the honor to submit the following report of a survey of Kennebec River, Maine, from Waterville to the steamboat wharf at Augusta:

The survey was begun at Waterville August 3, and completed to Augusta September 19, 1891, the total length of river surveyed being 18 miles. A triangulation was made to cover the entire length of river surveyed and consisted of 114 triangles. The triangulation points, wherever practicable, were marked by drill holes in ledge or large bowlders along the banks of the river, 88 of them being so marked. Each angle was read three times and the angles in each triangle made to balance within one minute or less. Five base lines were measured with a standard steel tape 200 feet long at nearly equal intervals in the length of the survey. The track of the Maine Central Railroad, which follows the river closely, afforded good opportunities for the measurement of the base lines. The shore line between triangulation points was run in by stadia measurement.

The depths were measured either with a graduated rod or with a 9-pound lead on a graduated brass chain, and each sounding was located by intersection with two transits on shore. The depths on the tidal portion of the river, below the dam at Augusta, are referred to the surface of the water at the lowest tide observed during the survey. Above the dam the soundings are referred to the surface of the water at the time of the survey, which was then at ordinary summer level. From the best information I could obtain at that time I should judge there would be about 1 foot less depth on the shoals in the upper part of the river at extreme low-water stages. Bench marks for the reestablishment of the water surface, to which the soundings have been referred, were marked by drill holes along the banks of the river.

Owing to lack of time, levels were run only from Waterville to the foot of the rapids at Carters Ledges, a distance of 3 miles, and from the dam to the steamboat wharf at Augusta, a further distance of three-fourths of a mile. Within this total length of 41 miles are included all the shoals which seriously interfere with the navigation of the river.

The survey was plotted to a scale of 1:6,000 and two tracings, showing the whole length of the river surveyed, are submitted.

The four worst shoals were also plotted separately to scales of 1:1,000 and 1:2,000, and from these larger charts the estimates have been made.

The tidal portion of the river extends from the steamboat wharf at Augusta to a point 4,000 feet above where there is a dam with a lock at its eastern end capable of passing a boat 90 feet long and 28 feet wido. This dam was built for the purpose of yielding power for manufacturing purposes, which is at present utilized by a large cotton mill on the west and a wood-pulp mill on the east bank. The lock and dam are kept in repair by the company operating the cotton mill, and a toll is charged for the passage of boats through the lock. This company is known as the Edwards Manufacturing Company. The lock is built of cut granite masonry, and is in fairly good condition. From the west side of the lock a timber crib work with its top 8 feet above low tide extends down the river 227 feet. This was built to give a slack-water pool at the entrance to the lock, but as the water from the wheels of the pulp mill is discharged with great velocity directly opposite this structure it fails to serve its purpose.

*Not reprinted; printed in House Ex. Doc. No. 76, Fifty-second Congress, first session.

At the time of the survey the surface of low tide at the dam was 3.29 feet higher than at the steamboat wharf. High tide at the steamboat wharf rose 5 feet, and at the foot of the dam only 1.8 feet, thus making the high-water surface nearly level. The lower miter sill of the lock is 5.5 feet below low tide at the foot of the dam, and only 2.21 feet below low tide at the steamboat wharf. The difference in level between miter sills of the lock is 15.39 feet. The top of the dam is 17.11 feet above low tide, and 15.31 feet above high tide at its foot, and 7.22 feet above the level of the upper miter sill of the lock.

One thousand and fifty feet above the steamboat wharf the river is crossed by a wagon bridge, and 850 feet farther up it is crossed by the bridge of the Maine Central Railroad. Neither of these bridges have drawspans. The lower chord of the wagon bridge is 33.4 feet above low tide, and 28.4 feet above high tide. The lower chord of the railroad bridge is 46.86 feet above low tide, and 43.60 feet above high tide. About two years ago the wagon bridge was rebuilt. The old bridge had two spans with one pier near the middle of the river, and the new bridge has three spans with two piers in the river, one on either side of the old central pier. The masonry of this old pier was taken down but the crib-work foundation still remains and there is only 14 feet of water on it at low tide. The channel between this old foundation and the new easterly pier has a width of only 75 feet.

From the steamboat wharf to the wagon bridge there is a channel depth of 10 feet or more at low tide. Between the bridges there is a shoal 500 feet long with a depth on it of only 24 feet at low tide. Just above the railroad bridge there is a shoal 300 feet long with a least depth of 2 feet, and at the entrance to the lock another shoal with a depth of less than 2 feet on it at low tide. The great difference in level of 3.29 feet between low tide at the foot of the dam and at the steamboat wharf of course gives rise to a very strong current. Most of this difference in level is taken up on the shoals above and below the railroad bridge, and the current is so strong at low tide that it is almost impossible to row up in a small boat.

From the dam to Vassalboro, 12 miles above the steamboat wharf at Augusta, the river is simply a mill pond, and has a barely perceptible current. This portion of the river varies in width from 500 feet to 1,100 feet, and has a navigable channel from 10 feet to 30 feet deep. Five miles above Augusta there is a small island in the river known as Five Mile Island. There is, however, a good navigable channel on either side of it. From Vassalboro to the foot of the rapids at Carters Ledges, a distance of 2 miles, the river shoals rapidly, and there is a navigable channel through this portion of only 6 feet depth. Between the foot of the rapids at Carters Ledges and Waterville, a distance of 34 miles, the water surface has a slope of 8.63 feet. Most of this slope occurs on the three shoals with which this part of the river is obstructed, and which are known as "Carters Ledges," "Pettys Rips," and "Fort Point Rips." At the time of the survey the current over these shoals was so swift that the only way to ascend them with a small boat was by towing along shore.

Opposite the steamboat landing at Waterville there is a basin having a depth of more than 17 feet. At the lower end of this basin, and about one-fourth of a mile below the steamboat landing, there is the shoal known as "Fort Point Rips," which has a least depth on it of 1.8 feet. In a length of 2,100 feet on this shoal the slope of the water surface was 2.5 feet. From the foot of Fort Point Rips to the head of Pettys Rips, a distance of 6,100 feet, there was a fall of 1.74 feet. Between these shoals there is a navigable channel 5 feet deep, obstructed at one point only by a shoal 100 feet long on which there is a least depth of 4.6 feet. At Pettys Rips the channel is very narrow and has a least depth of 2.5 feet. In a length of 2,800 feet over this shoal there is a fall of 2.44 feet and 1.5 feet of this fall is taken up in a distance of 900 feet at the head of the shoal. From the foot of Pettys Rips to Carters Ledges, a distance of 4,200 feet, there is a fall of 0.8 foot. Through this pool there is a channel 5 feet deep obstructed at one point by a shoal 350 feet long, on which there is a least depth of 4.1 feet. At Carters Ledges the bottom of the river is almost all solid rock, and ledge crops out above the water surface in a number of places. There is a practicable channel between these ledges which has a depth almost the entire distance of 6 feet or more, but at one point it is obstructed by ledge, on which there is only 4.4 feet. For a length of 1,000 feet over this shoal there is a fall in the water surface of 1 foot and a further fall 0.15 foot to the foot of the rapids, a distance of 800 feet.

Nine tests

At Fort Point Rips the shoal is caused by bowlders and coarse gravel. of the bottom were made on this shoal by driving a steel rod from 6 to 8 feet below the water surface without encountering ledge above a depth of 6 feet.

At Pettys Rips an irregular reef of ledge extends from the eastern bank nearly across the river, leaving a channel only 75 feet wide along the westerly shore. This channel is obstructed by bowlders and coarse gravel, and by tests made with the steel rod underlying ledge was found to extend across the head of the channel at a depth of 5 feet below the water surface.

The width of the river between Vassalboro and Waterville varies from 400 to 800

feet, the general width being 500 feet. The banks of the river throughout the entire distance from Augusta to Waterville are stable, being generally coarse gravel or ledge, with sand a small part of the distance. At only three places is any marked caving taking place, and at these points it is not great enough to be of any serious consequence.

For a number of years past the river has been used almost exclusively for the floating of loose logs from the headwaters of the Kennebec and its tributaries to the mills along the banks, or to a point 2 miles below Augusta, where they are made into rafts to be transported farther down the river. The value of these logs when sawed is estimated at over a million dollars annually. This industry is managed by a company which has almost completely appropriated the river as a flume for its logs during five or six months of the year, and has by means of piers, buoys, and chained logs constructed booms, which, in several places, have entirely closed the channel to navigation during the logging season. At the time of the survey the "drive" was at its height, and the logs interfered greatly with the work, and in three or four places were so jammed as to make a satisfactory examination impracticable.

The present steamboat navigation of the river consists in a light-draft stern-wheel boat built between two and three years ago by a company of citizens of Waterville, to ply between Augusta and that point. This boat proved to be of greater draft than was expected, drawing when loaded about 24 feet of water. For this reason it could only run for a month or two in the spring and before the water had dropped to summer level. Beside the shoal water it had to contend with the floating logs which at some of the worst places, especially Pettys Rips and Carters Ledges, occupy the entire channel.

The improvement desired seems to be for practicable navigation for light-draft boats and barges from Augusta, the present actual head of navigation, to Waterville. These boats and barges would be used for transporting bulky freight, mostly coal, up the river. The Maine Central Railroad follows the river closely from Augusta to Waterville, but it is claimed by citizens of Waterville that by making the river navigable the saving in freight rates to Waterville would be large enough annually to justify a moderate expenditure for the improvement. The trouble caused by floating logs would have also to be in some way abated to make navigation safe. To force the logging company to raft their logs below Waterville would be so expensive as to seriously cripple the industry. The only practicable method would appear to be to compel the logging company to construct a boom almost the entire length of the river which would leave a channel free from logs and sufficient for safe steamboat navigation. At the narrow places where it would be impracticable to divide the channel a sufficient force of men would have to be kept on duty by the logging company to check back the logs at such times as steamboats wished to pass.

The simplest improvement for the upper part of the river would be the construction of a lock and dam at Carters Ledges, or at Vassalboro, but the cost (roughly $125,000) would be out of proportion to the benefits to be derived and would still leave the part of the river below the dam to be improved. Another objection to this plan of improvement is that by raising the water high enough to give a navigable depth at Fort Point Rips the water power at Waterville would be to some extent interfered with.

The estimate herewith submitted is to obtain a channel 60 feet wide on the bottom and 5 feet deep at the stage of water to which the soundings on the map are referred. Such channel could be obtained by dredging, at all the shoals except Carters Ledges where the removal of a small amount of ledge would be necessary. This width and depth for the channel was fixed upon as they are the greatest which can be secured without removing large quantities of ledge.

At extreme low-water stages there would be at least 1 foot less depth on the shoals, leaving a navigable depth of not more than 4 feet at such stages after the improvement is completed. The material to be dredged is all coarse gravel and bowlders. The rock to be removed at Carters Ledge is solid ledge.

The prices given in the estimate are based on the expectation of the work being done by contract, and above the dam competition would be limited to such small dredges as can pass through the lock. A lump sum of $500 is added to the estimate for the removal of bowlders from the channel between the points to be dredged. The channels proposed have been made as nearly straight as practicable while following closely the line of deepest water. The locations of the proposed cuts are marked on the tracings submitted.

ESTIMATE.

Dredging coarse gravel and bowlders below dam at Augusta, 11,548 cubic

yards, in scows, at $1.25..

At shoal below Pettys Rips, 1,100 cubic yards, in scows, at $1.50 .
At Pettys Rips, 5,225 cubic yards, in scows, at $1.50 ..

$14,435.00

1,650.00

7,837.50

At shoal above Petty Rips, 300 cubic yards, in scows, at $1.50..
At Fort Point Rips, 10,567 cubic yards, in scows, at $1.50.
Removal of ledge at Carters Ledges, 165 cubic yards, at $5.
Removing bowlders from channel

Contingencies....

Total....

450.00 55,850.50 825.00

500.00

4, 252.00

45, 800.00

If it should be thought advisable to add 50 feet to the length of the lock at Augusta, an improvement which is said to be desired, $25,000 would have to be added to this estimate, making a grand total of $70,800 as the cost of the whole improve

ment.

Very respectfully, your obedient servant,

Lieut. Col. PETER C. HAINS,

Corps of Engineers, U. S. A.

F. S. BURROWES,
Assistant Engineer.

APPENDIX B.

IMPROVEMENT OF CERTAIN RIVERS AND HARBORS IN MASSACHUSETTS.

REPORT OF LIEUTENANT-COLONEL S. M. MANSFIELD, CORPS OF ENGINEERS, OFFICER IN CHARGE, FOR THE FISCAL YEAR ENDING JUNE 30, 1892, WITH OTHER DOCUMENTS RELATING TO THE WORKS.

IMPROVEMENTS.

1. Newburyport Harbor, Massachusetts.
2. Merrimac River, Massachusetts.
3. Powow River, Massachusetts.
4. Ipswich River, Massachusetts.

5. Harbor of refuge, Sandy Bay, Cape
Ann, Massachusetts.

6. Gloucester Harbor, Massachusetts.
7. Manchester Harbor, Massachusetts.
8. Salem Harbor, Massachusetts.
9. Lynn Harbor, Massachusetts.

10. Winthrop Harbor, Massachusetts.
11. Boston Harbor, Massachusetts.
12. Weymouth River, Massachusetts.
13. Hingham Harbor, Massachusetts.
14. Scituate Harbor, Massachusetts.
15. Plymouth Harbor, Massachusetts.
16. Wellfleet Harbor, Massachusetts.
17. Provincetown Harbor, Massachusetts
18. Chatham Harbor, Massachusetts.

UNITED STATES ENGINEER OFFICE, Boston, Mass., July 8, 1892. GENERAL: I have the honor to transmit herewith annual reports for the works of river and harbor improvements in my charge for the fiscal year ending June 30, 1892.

Very respectfully, your obedient servant,

S. M. MANSFIELD,

Brig. Gen. THOMAS L. CASEY,

Lieutenant-Colonel of Engineers.

Chief of Engineers, U. S. A.

BI.

IMPROVEMENT OF HARBOR AT NEWBURYPORT, MASSACHUSETTS.

Newburyport is situated on the south bank, 24 miles approximately, from the mouth of the Merrimac River. The river empties into the Atlantic Ocean midway between Cape Ann and Portsmouth, or about 30 miles a little east of north from Boston in a direct line.

The outlet of the river between Plum Island and Salisbury Point is 1,000 feet wide and 30 feet deep at mean low water. At a distance of nearly a mile outside lies a sandy bar, thrown up by wave action, through which, previous to the improvement, a channel, variable in position, direction, and depth, was maintained by the current of the river, increased by the tidal prism in a large interior basin, due to a range of tides equaling 7 feet.

For 1,000 feet outward from the gorge toward the crest of the bar the current was able to maintain a channel of navigable width and 18 feet deep at mean low water, and for a further distance of 1,500 feet a

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