the head of ordinary continuous navigation on the Snake, is $4,554. On the Columbia, between the Snake and Priest Rapids, there does not appear, from examinations and reports of pilots, to be any need of improvement; but I judge it is well to allow $100 per mile for removal of obstructions which may appear at extreme low stage. Above Priest Rapids, except at Cabinet and Rock islands, where the channels are bad, the river is like the original condition of the route from Celilo to Lewiston, whose improvement is costing about $500 per mile. Apply ing this rate to the Foster Creek reach, and omitting the principal rapids named above, we have $67,500. Comparing these rapids to the minor cascades, where rock work is in progress, as of equal difficulty but of double extent, cost of required improvement of the former may be judged to be $400,000, or in the neighborhood of $480,000 for the Foster Creek and Grand Ronde reaches. While this amount could not be judiciously expended in one year, because the working season is too short, more advantageous contracts for the work could be made under a total appropriation, available in annual installments, than under a partial amount. This proposed extended improvement, like that now in progress, is rock removal from channels between stable banks, where navigation is impeded by bowlders, reefs, and rock masses. Beyond Foster Creek there are 400 miles of navigable water on the main river, reaching north of the Canadian Pacific Railroad, and nearly half as much on the Kootenay, broken by two places where canals or portages will be required, No estimate is presented for the portion in the United States since there is no present demand for navigation. OPERATIONS DURING THE YEAR. These consisted of an instrumental examination of the Snake River below Lewiston, and in contract work on the Snake at Five-Mile Rapid and at the reef next below Five-Mile. Work at Little Goose Island and Log Cabin Island Rapids is included in the contract, but has not been undertaken. Extended time of contract expiration is October 31, 1884. At Five-Mile Rapids, rock projections aggregating 22.02 cubic yards were removed. Two of the rocks, designated as 4 and 5 on the progress map herewith, endangered descending steamers. Rocks 4 and 6 impeded ascending boats. Removal of these rocks has made channels of least depth and width of 5 and 100 feet respectively. A difficulty remains in the strength of current, caused by an excessive rate of fail at the crest of the rapid. A reduction of this slope can well be undertaken after other rapids are improved to afford as safe a passage as now afforded at Five-Mile. The removal of channel rocks complied with the existing project. Since the completion of the work, the steamer Spokane has brought down full loads, experiencing no difficulty in safely passing the rapid, which was formerly the worst one between Riparia and Ainsworth. One of these trips was made at the lowest recorded stage. Difficulties in the passage of the rapid and over the reef below decrease as the river rises. At the reef below Five-Mile, the river has an unusual width. Near the left shore are two channels, throughout which were irregularly scattered bowlders and rock points projecting from the shoal reef bottom. The extreme left channel was selected for improvement, as it afforded the greater general depth and presented the fewer obstructions. From it were removed 18 bowlders and rock points, aggregating 26.76 cubic yards. Only those rocks which were 3 feet and less submerged were removed, and their removal was to a depth of 5 feet below low water. This gave a depth of water at no place less than 33 feet in a channel nearly straight, and 100 feet wide where narrowest. There yet remains at the head of the channel a large area of reef rock submerged from 31⁄2 to 5 feet and presenting a very irregular surface. Lower down are a few bowlders and projecting points, the removal of which will be required whenever a free depth of 5 feet below low water is called for. The passage of this shoal is now considered safe for all steamers on the river. The work was done in October and November. Fair weather generally prevailed. The river fluctuated between 0.2 and 0.6 feet above low water. Assistant Engineer P. G. Eastwick was the inspector. He gives the following description of the contractor's operation: In the prosecution of the work the contractor used a scow 66 feet long and 17 feet wide fitted with quarters and a mess-room for the workmen, and with all the appliances required on the work. In drilling the rock the men worked on a platform placed aft of the stern of the scow, which was securely moored by ropes and chains to anchors or ringbolts in such a manner as to bring the platform over the rock. The drilling was done by hand, 3-inch diameter holes being drilled to a depth of from 6 to 12 inches below the plane to which it was intended to excavate, in the larger rocks the holes being placed to 4 feet apart. Into these holes were placed tubes 24 inches in diameter, loaded with No. 1 giant powder, the tops of the tubes projecting above the surface of the water. Where the current was moderate tin tubes were used, but in the stronger currents, condemned boiler tubes were substituted, the tin bending and breaking under the force of the current. The difficulty of charging the holes and exploding the charges under water in a strong current rendered the use of the tubes necessary. Each charge was exploded with a separate fuze. Upon suspension of the contract work, and on account of an unusually favorable stage and weather and need of information about the smaller rapids, whose improvement was not included in the present and original estimate, Mr. Eastwick made a careful river examination from Lewiston down, and has incorporated in his report, which is herewith, further data derived from railroad surveys. July 1, 1884, amount expended during fiscal year, exclusive of $5, 140 29 outstanding liabilities July 1, 1883 $3,085 26 July 1, 1884, outstanding liabilities... 130 57 3,215 83 July 1, 1884, amount available..... 1,924 46 Amount appropriated by act approved July 5, 1884 . 20,000 00 Amount available for fiscal year ending June 30, 1885..... 21,924 46 Amount (estimated) required for completion of existing project.... 36,000 00 Amount that can be profitably expended in fiscal year ending June 30, 1886... 136,000 00 Abstract of contract for improving Upper Columbia River, Oregon, in force during the fiscal year ending June 30, 1884, in charge of Capt. Charles F. Powell, Corps of Engineers. Contract expiration was December 31, 1883. Time extended to October 31, 1884, in accordance with Department letter of December 10, 1883. REPORT OF MR. PHILIP C. EASTWICK, ASSISTANT ENgineer. UNITED STATES ENGINEER Office, SIR: In compliance with your instructions, I made a rapid examination of the rapids and other obstructions on Snake River between Lewiston and its mouth. I left Lewiston on the 12th of December, in a bateau, accompanied by three men, and reached Ainsworth, near the mouth of the river, on the 29th, making the time of eighteen days spent on the river. The weather during the latter part of this period was very stormy and was accompanied by the strong up-stream winds which are common on the river during the winter. Finding it impossible to make satisfactory headway in the boa during the bad weather, I was detained in all four days thereby. Six days were consumed in examining Lower Log Cabin and Little Goose rapids, the clearing of which is now under contract. This left but eight days devoted to the examination of the other parts of the river. During the progress of the examination the fluctuation of the river, as ascertained from records kept at Riparia and Ainsworth, was as follows: At Riparia, from low water to 1.1 feet above low water.* At Ainsworth from low water to five-tenths feet above low water. The designated low water is the lowest recorded water plane as ascertained from continuous records at Riparia since April 1, 1882, and at Ainsworth since March 1, 1882. The low stage was favorable to the examination, but the limited time and small force at my disposal prevented anything more than a general examination. Appended hereto is a descriptive list of all rapids, swifts, shoals, shipping points, &c., passed during the examination. The list embraces 51 places where rapids, swifts, or shoals occur. The five principal rapids, in the order of their occurrence, are as follows: Texas Rapid, Palouse Rapid, Pine Tree Rapid, Fish Hook Rapid, and Five Mile Rapid. These are all below Riparia and are characterized by a great slope and strong currents through narrow rock-bound channels. Palouse and Five Mile rapids, it is believed, have been cleared of dangerous rocks to a depth at low water of at least 5 feet, so as to offer no insurmountable impediment to steamers drawing 4 feet of water. The strong current is the only remaining impediment, but this can be easily overcome. Texas, Pine Tree, and Fish Hook rapids, though much improved by the work that has been done upon them, are yet in a condition very dangerous to the safety of both ascending and descending steamers. The present channels through them would be considered safe and ample in width and depth were it not for the very strong current induced by the excessive rate of fall. This current is now so strong at low water that ascending steamers cannot stem it. These rapids must be further critically examined and the direction, velocity, and slope of the currents ascertained before a plan for the effective removal of the obstacles to navigation can be intelligibly determined upon. It is probable that on one or more of these rapids the excessive fall will call for the use of locks to open them to navigation at extreme low water. The following list comprises all the other places where the low-water navigation is so seriously impeded as to call for their early improvement: Above Riparia.-Little Pine Tree Rapid, shoal below Bishop's Bar, rapid above Granite Point, Lower Log Cabin Rapid, and Little Goose Rapid. *In this report, low water at Riparia is minus 8 inches on local gauge, and at Ainsworth is 328 feet above railroad datum.-C. F. P. Below Riparia.-Gore's Dread, Long Crossing, Couch Island Rapid, bar below Ford's Island, Copeley's Cut-off, Three Island Bend, Tiger-head Crossing, Perine's Defeat, Ainsworth Bar, and bar at mouth of river. The passage of many of these places is impeded by strong currents and is accompanied by risk of damage to steamers. Intermediate between the rapids, shoals, &c., noted in the appended list are reaches of slackwater, sometimes of considerable length, where the general depth is ample for low-water navigation, and where no disturbance of the water indicates the presence of obstructions. From the river captains, however, I learn that the channel at many places is obstructed by submerged bowlders, requiring good pilotage to avoid. At none of these intermediate places, however, do I consider it necessary to make improvements until the channel at the more dangerous rapids is cleared. The bed of the river on the rapids, shoals, and swifts, except where otherwise noted in the appended list, is of flat, water-worn cobble-stones mixed with finer material and generally spotted over with boulders or projections of rock from concealed reefs below the cobble-stone. The cobble-stones are closely packed and make a very hard and firm bed, which the strongest currents of the river fail to move. It appears quite probable that, in most cases, where such material forms the obstructing bars, if once removed by blasting and scraping, they will not speedily reform. To estimate the amount of work to be done at each of the places where obstructions are found involves the defining of the channel, which it is impossible to do without a survey, more or less complete, made with appliances specially adapted to make the examination in swift water. The surveys and measurements of the obstructions have heretofore been made at the time the improvements were in progress, with the use of the contractor's scow securely moored at the obstructions. Having no special facilities to enable me to do justice to that part of the work, estimates of the quantity of work to be done at most of the rapids, swifts, and shoals are necessarily omitted. From maps and profiles of surveys made by Mr. G. R. Maxwell and by myself on Snake River in November, 1871, which have been kindly furnished to me by General Anderson, engineer in chief of the Northern Pacific Railroad, and by Mr. V. G. Bogue, his principal assistant on this coast, I have compiled the accompanying table of distances, and table showing elevations and rate of fall on the river. The distance from a point on the Clearwater River opposite Lewiston to the mouth of Snake River below Ainsworth, as ascertained from the maps referred to, is 137 miles. The survey follows closely along the right bank of the river, and the channel distance consequently will not much exceed this. Snake River, from Lewiston to its mouth, passes through a deep and narrow valley, flanked on both sides with high, precipitous slopes, terminating quite frequently at or near the river in vertical bluffs of columnar basalt rock. These slopes are surmounted by a heavily rolling plateau extending back into the interior. Opposite Lewiston this plateau has an elevation of 2,100 feet above the river. As the river is descended the elevation falls until Ainsworth is reached, near the mouth of the river. On both the banks of the river at frequent intervals are to be found high rolling benches at the foot of the steep slopes of the main valley. The cultivated area in the valley is confined to these benches, as the flanking slopes of the valley are too precipitous to be used for that purpose. The high rolling plateau surmounting the valley slopes is, with but little exception, excellent grain land. It is rapidly being absorbed by settlers under the homestead and pre-emption laws. The land is now devoted to the culture of wheat and to sheepgrazing. The former industry is increasing at the expense of the latter, the sheepherder yearly finding his grazing grounds encroached upon by the farmer. The railroad of the Oregon Railway and Navigation Company leading to Portland terminates on the left bank of the river at Riparia, a point about midway between Lewiston and the mouth. From Riparia the road follows down the left bank of the river a distance of 4.6 miles to Grange City, at the mouth of the Tucanon, up the valley of which stream it passes into the country south of the river. Riparia is now, and has been since the completion of the railroad, the lower terminus of a steamboat route terminating above at Lewiston. This division of the river is more free from obstructions than the division below Riparia, and is navigable at all times except when obstructed by ice, thongh at the lower stages only by the lightest draught steamers. The navigation of parts only of the lower division of the river is possible at extreme low water, and that only by the lightest draught steamers, the ascent of the river being practically barred at Long Crossing. With the present railroad connections navigation of the river will probably be continued under the two divisions named, the upper end of the lower division being at some point below the principal obstructing rapids. To the north of Snake River, and separated from it by a high intervening country, has recently been built the Palouse branch of the Northern Pacific Railroad, extend ing through Colfax to Moscow, Idaho. This railroad runs parallel to the river at a distance varying from 4 to 18 miles. Its construction tends rather to develop new fields than to diminish the trade of the river. * Hereto is appended the following: 1. Descriptive list of rapids, shoals, shipping points, &c., on Snake River below Lewiston. 2. Descriptive list of benches on Snake River. 3. Statement of crop of 1883 tributary to Snake River. 4. Table of distances of points on Snake River. 5. Table showing the elevation above the sea of the surface of the water at points on Snake River. Respectfully submitted. Capt. CHAS. F. POWELL, PHILIP G. EASTWICK, Corps of Engineers, U. S. A. DESCRIPTION OF RAPIDS, SHIPPING POINTS, ETC., ON SNAKE RIVER BELOW LEWISTON, IDAHO. 1. Lewiston, Idaho.-On the right bank of Snake River above the mouth of the Clearwater River. The grain and other agricultural products from the vicinity of Lewiston, on the right bank of the Snake and both banks of the Clearwater, are collected here for shipment.* 2. Lewiston Rapid.-Opposite Lewiston and above the mouth of Clearwater. The channel is straight, narrow, and deep, with a strong current and no obstructions. The strong current extends over a length of about 2,000 feet of the river, with a fall of 4.2 feet. At the head of the rapid 2.6 feet of this fall occurs in a length of 600 feet (an average of 0.43 feet per 100 feet of length), inducing an excessively rapid current. Through this current steamers ascend at low water with the assistance of line and capstan. (See profile of water-surface on left shore.) At a stage of five-tenths feet above low water the intensity of the current is so far reduced that steamers can ascend without lining. The intensity of the current can be reduced by widening the channel at the place of greatest slope, thus lowering the crest and distributing the fall more uniformly over a greater length. No improvement is at present required at this rapid, as the impediment which is not insurmountable is met with only at the extreme low stage. 3. Clearwater River.-Empties into Snake River from the right immediately below Lewiston Rapid. 4. Swift above Skeel's Landing.—Short, straight, and deep; current moderate and no obstructions. 5. Skeel's Landing on right bank.-Grain from the north and northeast is collected here for shipment. 6. Shoal below Skeel's Landing.-For a short distance soundings show a minimum depth of 4 feet. The general depth above and below is 5 feet. Small bowlders are scattered through the shoal. The moderate current enables steamers to pass without difficulty. No improvement required at present. 7. Rapid above White's Ferry.-Channel slightly curved; water deep. The total fall is 3.2 feet in a distance of about 2,100 feet. At two points on the rapid the river is contracted to a width of from 300 feet to 350 feet, causing chutes where the water falls for short distances at a more rapid rate, and the current, which throughout the rapid is generally strong, is intensified. At the chutes the water is very turbulent. The strong current on this rapid, though retarding ascending steamers, does not necessitate a resort to lining. Above the head of the rapid is a diagonal bar extending from foot of island on the left, above, down to the exposed bar on the right, below. This makes an extensive shoal, spotted with numerous small bowlders, to avoid which steamers are obliged to follow a tortuous course. General depth on the shoal is 4 feet. (See profile and sketch.) *For amount of products, see table following. |