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tion of the class of smaller vessels navigating Puget Sound, contemplates dredging a channel 100 feet wide and 4 feet deep in Swinomish Slough and across the flats at its northern and southern entrances to a sufficient depth of water in Padilla Bay and Skagit Bay, forming a basin near Goat Island by widening the channel to 200 feet for a length of 750 feet, and construction of dikes where necessary for protection of the cut and retention of wasted material. The total cost of this work is estimated at $122,000. Printed as House Ex. Doc. No. 31. (See also Appendix T T 14.) EXAMINATION, BY BOARD OF ENGINEERS, FOR SHIF CANAL TO CON

NECT LAKES UNION, WASHINGTON, AND SAMAMISH WITH PUGET SOUND, WASHINGTON, MADE IN COMPLIANCE WITH PROVISIONS OF RIVER AND HARBOR ACT APPROVED SEPTEMBER 19, 1890.

In compliance with the provisions of the act a Board of Engineers, consisting of Col. G. H. Mendell, Maj. Thomas H. Handbury, and Capt. Thomas W. Symons, Corps of Engineers, was constituted to select and survey location and estimate cost of proposed ship canal, in Seattle and its vicinity, to connect lakes Union, Washington, and Samamish with Puget Sound. The report of the Board was submitted under date of December 15, 1891, and was transmitted to Congress and printed as House Ex. Doc. No. 40, Fifty-second Congress, first session.

A canal connecting lakes Samamish and Washington with a lock near Lake Washington to overcome the difference, 10.5 feet, in the level of the two lakes, is estimated to cost $4,927,230.

The proposed route and project for a canal connecting Lake Washington with Puget Sound contemplates constructing a canal 2,600 feet long, 80 feet wide at bottom and 158 feet wide at the water line, and 26 feet deep through the portage between Union Bay, in Lake Washington, and Lake Union, with a masonry lock 400 feet long, 50 feet wide, 26 feet deep over sill, and with a lift of about 7.5 feet; dredging channels to connect this canal with deep water in Lake Washington, and across Lake Union; and constructing a canal 6,700 feet long, 80 feet wide at bottom and 158 feet wide at the water line, and 26 feet deep, connecting Lake Union along its outlet with the head of Salmon Bay. From the head of Salmon Bay to Puget Sound two routes are considered by the Board; one by way of Salmon Bay and Shilshole Bay, with a lock near the sound 400 feet long, 50 feet wide, and 16.6 feet deep over sill at low tide; the other by way of Smiths Cove and a canal 80 feet wide at bottom, 158 feet wide at the water line, and 26 feet deep, to be constructed across the neck of land between the head of Salmon Bay and Smiths Cove with a lock near the sound similar to that projected for Shilshole Bay. The construction of a basin and formation of a channel through the shoals at the outlet of the lock are also contemplated. The estimated cost of the proposed canal between Lake Washington and Puget Sound by the two routes, not including damages for lands submerged, is as follows: Smiths Cove route...

$3,500,000 Shilshole Bay route

2, 900,000 Concerning the comparative advantages of the two routes the Board states:

The Shilshole Bay system costs $600,000 less than that by Smiths Cove. On the other hand, the latter route possesses advantages in that its entrance is in the har. bor of Seattle, whereas the entrance to the other is 54 miles distant; and secondly, the Smiths Cove entrance and lock are less expossed to bombardment by an enemy's fleet. For these reasons the Smiths Cove route is to be preferred. (See Appendix T T 15.)

ENG 92-25

IMPROVEMENT OF WILLAMETTE RIVER, OREGON, AND OF LOWER

COLUMBIA RIVER AND ITS TRIBUTARIES, OREGON AND WASHINGTON.

Officer in charge, Maj. Thomas H. Handbury, Corps of Engineers, having under his immediate orders Lieut. Edward Burr, Corps of Engineers, to November 14, 1891, and Lieut. Harry Taylor, Corps of Engineers, since November 12, 1891; Division Engineer, Col. G. H. Mendell, Corps of Engineers.

1. Mouth of the Columbia River, Oregon and Washington.-The proj. ect under which this work is being carried on was adopted in 1884. It contemplates providing a channel across the Columbia River Bar, having a depth of 30 feet at mean low tide. This is to be effected by concentrating the water flowing over the bar and increasing the resultant currents to such a degree as to procure the desired depth. Any work for accomplishing this end must be more or less tentative in its character. The work which is now in progress is the building of a low-tide jetty, starting from Fort Stevens, on the South Cape, and extending in a westerly direction, with a slight curve to the south, out across Clatsop Spit, for a distance of 4 miles, more or less, as circumstances may require, to a point about 3 miles south of Cape Disappointment. The jetty is constructed of stone, resting upon a mattress foundation about 40 feet wide and from 21 to 5 feet thick. The stone extends to the level of 4 feet above mean lower low water. The material thus far has been placed in position from a jetty tramway supported upon piles driven along the line of the jetty and 24 feet above the level of low tide. The tramway is a double-track 3-foot-gauge railroad, the tracks being 13 feet between centers. The material is landed at the wharf and transported to place over these tracks, which are built in advance of the main work.

Before the commencement of this work the channel or channels over this bar were very capricious in location and variable in depth. The depths were usually from 19 to 21 feet, and the channels varied in number from one to three, and in location through nearly 1800 from Cape Disappointment to Point Adams.

The results of the jetty already constructed are very marked in the building up of Clatsop Spit and in the effects produced by the concentration of water upon the bar. There is now a straight channel, having a width of one-fourth mile, with a depth nowhere less than 29 feet, and for a width of 1 mile a depth of 27 feet. At the end of the last fiscal year the shortest distance from the 30-foot curve on the outside to the same on the inside of the bar was 3,000 feet. This distance is now reduced to 1,200 feet. These depths refer to the plane of the mean of lower low waters.

The first appropriation for this improvement was made in the river and harbor act approved July 5, 1884. The total amount appropriated to the end of the present fiscal year for carrying out the project is $1,337,500. The amount expended, including outstanding liabilities, is $1,313,168.88, leaving a balance of $24,331.12, applicable to the further prosecution of the work.

At the end of last fiscal year the jetty tramway was at station 239 + 52, with the mattress work at station 235 + 40. Station 25 + 80 is regarded as the root or beginning of the jetty proper. During the month of July the tramway was extended 1,088 feet. Station 250 + 20 is regarded as the end of the jetty. This is 47 miles from the begin

ning, at station 25 + 80. From this station, east, to the end of the present wharf the distance is 3,080 feet, making the distance from the end of the wharf to the outer end of the jetty a little over 4.8 miles.

In view of the results obtained by the jetty at the end of the last. fiscal year, as shown by the soundings taken at that time on the bar, it was deemed advisable to stop the construction of the jetty when it arrived at a point 41 miles from the inner end, and await further developments, which would be shown by the soundings to be taken during June of this year.

Under the contract dated January 22, 1891, in force with Joseph E. Smith, 150,500 tons of rock was received during the year. The total amount of rock received from all sources since the commencement of the work is 478,890 tons.

About 25,000 tons of this rock was used in securing the root of the jetty and in protecting the buildings and railway between that point and the wharf. The balance has been distributed along the line of the jetty. From the end of the jetty back for a distance of 2,500 feet the rock is raised to a level of 4 feet above datum; for 13,000 feet it is at a datum; for 5,200 feet it will average 4 feet above; for the remaining distance it will run from this level to high water. Near the inner end of the jetty it was found to be necessary to pile rock well up toward the high-water line to protect the piling of the tramway from the heavy drift brought down by the river during the winter and spring. At places along the line of the jetty it was observed that there was a decided tendency during the last of the flood tides and the first of the ebb for the water to flow across the jetty in great volume and with considerable velocity. Where this was the case the sand would not deposit in the vicinity, but would be scoured out, increasing the area of the water way. At these places rock was dumped in until this action ceased. It was found that when the jetty reached the height of about 4 feet above the mean level of low water, the flow during both ebb and flood was under control. The sand was deposited to the level of low water and above, in many instances, on both sides of the jetty.

On June 9, 10, and 11 surveys were made upon the bar at the mouth of the Columbia River with the view to developing the present condition of the channel in that locality. The conditions were favorable for this work, and the results inake a very satisfactory showing. The 27foot channel is now about 1 mile wide, and the 25-foot channel about 2 miles. The indications from this survey are all favorable to a permanent depth of channel of at least 30 feet. The shortest distance between the curves of this depth on the two sides of the bar is now but 1,200 feet.

The original estimate for the construction of this work was $3,710,000; of this amount there has already been appropriated to June 30, 1892, $1,337,500. There was a balance on hand at that date of $24,331.12, exclusive of outstanding liabilities. July 1, 1891, balance unexpended .....

$274, 710, 46 June 30, 1892, amount expended during fiscal year.

220, 913. 69 July 1, 1892, balance unexpended ...

53, 796. 77 July 1, 1892, amount covered by uncompleted contracts.

29, 465. 65 July 1, 1892, balance available....

24, 331, 12 Amount appropriated by act approved July 13, 1892

350, 000,00 Amonut available for fiscal year ending June 30, 1893..

374, 331, 12

Añount (estimated) required for completion of existing project...... $175,000.00 Submitted in compliance with requirements of sections 2 of river and

harbor acts of 1866 and 1867. (See Appendix U U 1.)

2. Construction of canal at the Cascades, Columbia River, Oregon.The general scope of the improvement which it is desired to effect at the Cascades of the Columbia River includes a reach of about 41 miles, where the river rushes through a narrow gorge in the Cascade Mountains. The fall in the distance is about 45 feet at high water and 36 feet at low water. The principal obstruction to navigation occurs at the upper end of the reach, known as Upper Cascades. The project for the improvement contemplates that the river should be improved below the Upper Cascades by removing bowlders and projecting points in the bed and banks so as to give good navigable water from its lowest up to a 20-foot stage. The fall at the Upper. Cascades is to be overcome by digging a canal of 3,000 feet length across the neck of a low projecting spur, around which the river is forced at the entrance to the gorge, and placing in this a lock and other suitable structures, which would permit of the passage of boats up to a 20-foot stage of water in the river; this lock and canal to be so arranged that, should the future necessities of commerce so demand, additional structures may be added which will permit of navigation at much higher stages.

The first part of this project, that of improving the river below the foot of the Upper Cascades, is essentially finished.

The difference of level between the head and foot of the canal as now established is 15 feet at high water and 24 feet at low water, and difference in height between high and low water at the foot is 54 feet, and at the head 45 feet. The plan on which the future work in the canal, with its lock and accessories, is to be prosecuted, has for its object to make this portion of the river available for navigation to a stage up to 20 feet at the earliest possible moment, with the funds that are from time to time appropriated for the purpose.

At the commencement of the present fiscal year there was available for the prosecution of the work $204,691.71. At that time the principal work in progress was cutting stone, there being about fifty cutters employed. Other operations excepting current repairs were suspended on account of high water in the Columbia River. By the 1st of August the water had receded sufficiently to permit the lock pit to be punped out. On the evening of the 7th, the water was practically all out of this. Preparations were at once made for resuming the work of placing concrete and setting stone in the north wall of the masonry of the lower lock and guard gate. Quarrying stone was resumed about the 20tir of July. Concreting and stone setting was resumed August 20. Work was pushed forward actively until December 5, when it became necessary to suspend the making of concrete and stone setting. On the 11th of December stonecutting was discontinued. By the 19th the whole laboring force was discharged. The office force was moved to Portland on that date and employed during the winter in making up estimates of the season's work and in the preparation of detailed drawings for future work. The property at the works during this time was left in charge of watchmen. On April 4 the office force returned and the stonecutting and quarrying was resumed and continued to June 30. At that date the balance available for the prosecution of the work was $17,833,60.

The progress during the year towards completion is represented by the following general results. There were cut 2,074 cubic feet of

dimension granite, 27,117 cubic feet dimension basalt, and 50,019 cubic feet basalt face stone. There were quarried 2,110 cubic yards of dimension stone and 604 yards of rubble from the bowlders found on the ground leased for this privilege.

Quantities of stone laid: In lock walls, 334 cubic yards of granite, 651 cubic yards basalt dimension stone, 2,003 cubic yards basalt face stone; in canal walls, 37 cubic yards basalt face stone, and 223 cubic yards dry rubble. Sixty-seven cubic yards of concrete culvert pipe 39 inches diameter, 6 inches through, was laid in the south lock wall,

The amount of concrete made and placed during the year was 17,899 cubic yards. There were used in this 15,720 barrels Portland cement, 8,475 cubic yards sand, 13,984 yards gravel, and 1,001 yards broken stone. Seventy-seven sections of concrete pipe 3 feet long, 39 inches diameter, and 6 inches thick, were made.

The masonry constructed during the year is the north abutment of the lower lock and guard gates, except the coping, and about 300 feet of the south wall of the lock chamber. The total amount of this masonry is 21,214 cubie yards.

The buildings and plant are now in a good state of repair and everything is in readiness to push the work forward as rapidly as the funds available and other circumstances will permit.

The portage railway constructed over the Government grounds at Cascade Locks was finished about the middle of September. This road connects with two steamboats, one running above the Cascades to the Dalles, the other running below to Portland. During the year there were about 18,150 passengers and 5,000 tons of freight transported by these two boats.

The amount expended upon this work to June 30, 1892, is $1,856,183.53. The available balance on hand at that time is $17,833,60. The estimated amount to be appropriated to complete the work is $1,419,250. The amount estimated that can be profitably expended during the fiscal year ending June 30, 1894, is $1,419,250. July 1, 1891, balance unexpended..

$208, 483.71 June 30, 1892, amount expended during fiscal year: Portland office..

$190, 646. 11 Treasury Department

4.00

190, 650, 11 July 1, 1892, balance unexpended..

17,833. 60 Amount appropriated by act approved July 13, 1892.

326, 250.00 Amount available for fiscal year ending June 30, 1893

344, 083. 60 Amount (estimated) required for completion of existing project..... 1,419, 250.00 Amount that can be protitably expended in fiscal year ending June 30, 1894..

1,419, 250.00 Submitted in compliance with requirements of sections 2 of river and

harbor acts of 1866 and 1867. (See Appendix U U 2.)

3. Columbia and Lower Willamette rivers below Portland, Oregon.The object of this improvement is now to make and maintain a navigable channel from the city of Portland, Oregon, to the sea, having a low-water depth of 25 feet. There is included in this reach 12 miles of the Willamette River and 98 miles of the Columbia, measured along the deep-water channel. Before the commencement of the improvement in accordance with previous projects the low-water depth of channel at the shoalest places was between 10 and 15 feet. At the end of the present year there is a low-water depth of 20 feet throughout the entire

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